Version 21.52: Nov 05, 2021 Changed SELECT COUNT to SELECT EXISTS in some queries.

swad_API.c

@@ -535,10 +535,11 @@ static int API_GenerateNewWSKey (struct soap *soap,
    Str_Copy (WSKey,Gbl.UniqueNameEncrypted,API_BYTES_WS_KEY);
 
    /***** Check that key does not exist in database *****/
-   if (DB_QueryCOUNT ("can not get existence of key",
+   if (DB_QueryEXISTS ("can not get existence of key",
-		      "SELECT COUNT(*)"
+		       "SELECT EXISTS"
+		       "(SELECT *"
 			 " FROM api_keys"
-		      " WHERE WSKey='%s'",
+		        " WHERE WSKey='%s')",
 		       WSKey))
       return soap_receiver_fault (soap,
 	                          "Error when generating key",
@@ -769,10 +770,11 @@ static int API_CheckParamsNewAccount (char *NewNickWithArr,		// Input
       Str_RemoveLeadingArrobas (CopyOfNewNick);
 
       /***** Check if the new nickname matches any of the nicknames of other users *****/
-      if (DB_QueryCOUNT ("can not check if nickname already existed",
+      if (DB_QueryEXISTS ("can not check if nickname already existed",
-			 "SELECT COUNT(*)"
+			  "SELECT EXISTS"
+			  "(SELECT *"
 			    " FROM usr_nicknames"
-			 " WHERE Nickname='%s'",	// A nickname of another user is the same that this nickname
+			   " WHERE Nickname='%s')",	// A nickname of another user is the same that this nickname
 			  CopyOfNewNick))		// Already without leading arrobas
 	 return API_CHECK_NEW_ACCOUNT_NICKNAME_REGISTERED_BY_ANOTHER_USER;
 
@@ -786,11 +788,12 @@ static int API_CheckParamsNewAccount (char *NewNickWithArr,		// Input
    if (Mai_CheckIfEmailIsValid (NewEmail))	// New email is valid
      {
       /***** Check if the new email matches any of the confirmed emails of other users *****/
-      if (DB_QueryCOUNT ("can not check if email already existed",
+      if (DB_QueryEXISTS ("can not check if email already existed",
-			 "SELECT COUNT(*)"
+			  "SELECT EXISTS"
+			  "(SELECT *"
 			    " FROM usr_emails"
 			   " WHERE E_mail='%s'"
-			   " AND Confirmed='Y'",
+			     " AND Confirmed='Y')",
 			  NewEmail))	// An email of another user is the same that my email
 	 return API_CHECK_NEW_ACCOUNT_EMAIL_REGISTERED_BY_ANOTHER_USER;
      }
@@ -6052,9 +6055,10 @@ int swad__getLastLocation (struct soap *soap,
    The other user does not have to share any course with me,
    but at least some course of each one has to share center.
    */
-   if (DB_QueryCOUNT ("can not get session data",
+   if (DB_QueryEXISTS ("can not check if you can see user location",
-		       "SELECT COUNT(*) FROM "
+		       "SELECT EXISTS"
-		       "(SELECT DISTINCT deg_degrees.CtrCod"
+		       "(SELECT *"
+			 " FROM (SELECT DISTINCT deg_degrees.CtrCod"
 				 " FROM crs_users,"
 				       "crs_courses,"
 				       "deg_degrees"
@@ -6068,7 +6072,7 @@ int swad__getLastLocation (struct soap *soap,
 				" WHERE crs_users.UsrCod=%d"
 				  " AND crs_users.CrsCod=crs_courses.CrsCod"
 				  " AND crs_courses.DegCod=deg_degrees.DegCod) AS C2"	// centers of user's courses
-		       " WHERE C1.CtrCod=C2.CtrCod",
+			        " WHERE C1.CtrCod=C2.CtrCod)",
 	               Gbl.Usrs.Me.UsrDat.UsrCod,
 	               userCode))
      {

swad_ID_database.c

@@ -110,15 +110,16 @@ unsigned ID_DB_GetIDsFromUsrCod (MYSQL_RES **mysql_res,long UsrCod)
 
 bool ID_DB_CheckIfConfirmed (long UsrCod,const char ID[ID_MAX_BYTES_USR_ID + 1])
   {
-   /***** Get if ID is confirmed from database *****/
+   return
-   return (DB_QueryCOUNT ("can not check if ID is confirmed",
+   DB_QueryEXISTS ("can not check if ID is confirmed",
-			  "SELECT COUNT(*)"
+		   "SELECT EXISTS"
+		   "(SELECT *"
 		     " FROM usr_ids"
 		    " WHERE UsrCod=%ld"
 		      " AND UsrID='%s'"
-			    " AND Confirmed='Y'",
+		      " AND Confirmed='Y')",
 		   UsrCod,
-			  ID) != 0);
+		   ID);
   }
 
 /*****************************************************************************/
@@ -127,11 +128,13 @@ bool ID_DB_CheckIfConfirmed (long UsrCod,const char ID[ID_MAX_BYTES_USR_ID + 1])
 
 bool ID_DB_FindStrInUsrsIDs (const char *Str)
   {
-   return (DB_QueryCOUNT ("can not check if a string matches any user's ID",
+   return
-			  "SELECT COUNT(*)"
+   DB_QueryEXISTS ("can not check if a string matches any user's ID",
+		   "SELECT EXISTS"
+		   "(SELECT *"
 		     " FROM usr_ids"
-			  " WHERE UsrID='%s'",
+		    " WHERE UsrID='%s')",
-			  Str) != 0);
+		   Str);
   }
 
 /*****************************************************************************/

swad_account.c

@@ -787,7 +787,7 @@ static void Acc_CreateNewEncryptedUsrCod (struct UsrData *UsrDat)
      {
       Str_CreateRandomAlphanumStr (RandomStr,LENGTH_RANDOM_STR);
       Cry_EncryptSHA256Base64 (RandomStr,UsrDat->EnUsrCod);
-      if (!Usr_DB_ChkIfEncryptedUsrCodExists (UsrDat->EnUsrCod))
+      if (Usr_DB_GetUsrCodFromEncryptedUsrCod (UsrDat->EnUsrCod) <= 0)
          break;
      }
    if (NumTry == MAX_TRY)

swad_account_database.c

@@ -82,13 +82,15 @@ unsigned Acc_DB_GetUsrsWithID (MYSQL_RES **mysql_res,
 
 bool Acc_DB_CheckIfNicknameAlreadyExists (const char NewNickWithoutArr[Nck_MAX_BYTES_NICK_WITHOUT_ARROBA + 1])
   {
-   return (DB_QueryCOUNT ("can not check if nickname already existed",
+   return
-			  "SELECT COUNT(*)"
+   DB_QueryEXISTS ("can not check if nickname already existed",
+		   "SELECT EXISTS"
+		   "(SELECT *"
 		     " FROM usr_nicknames"
 		    " WHERE Nickname='%s'"
-			    " AND UsrCod<>%ld",
+		      " AND UsrCod<>%ld)",
 		   NewNickWithoutArr,
-			  Gbl.Usrs.Me.UsrDat.UsrCod) != 0);	// A nickname of another user is the same that this nickname
+		   Gbl.Usrs.Me.UsrDat.UsrCod);	// A nickname of another user is the same that this nickname
   }
 
 /*****************************************************************************/
@@ -97,12 +99,14 @@ bool Acc_DB_CheckIfNicknameAlreadyExists (const char NewNickWithoutArr[Nck_MAX_B
 
 bool Acc_DB_CheckIfEmailAlreadyExists (const char NewEmail[Cns_MAX_BYTES_EMAIL_ADDRESS + 1])
   {
-   return (DB_QueryCOUNT ("can not check if email already existed",
+   return
-			  "SELECT COUNT(*)"
+   DB_QueryEXISTS ("can not check if email already existed",
+		   "SELECT EXISTS"
+		   "(SELECT *"
 		     " FROM usr_emails"
 		    " WHERE E_mail='%s'"
-		            " AND Confirmed='Y'",
+		      " AND Confirmed='Y')",
-	                  NewEmail) != 0);	// An email of another user is the same that my email
+		   NewEmail);	// An email of another user is the same that my email
   }
 
 /*****************************************************************************/

swad_admin_database.c

@@ -100,16 +100,17 @@ unsigned Adm_DB_GetAdmsCurrentScopeExceptMe (MYSQL_RES **mysql_res)
 
 bool Adm_DB_CheckIfUsrIsAdm (long UsrCod,HieLvl_Level_t Scope,long Cod)
   {
-   /***** Get if a user is administrator of a degree from database *****/
+   return
-   return (DB_QueryCOUNT ("can not check if a user is administrator",
+   DB_QueryEXISTS ("can not check if a user is administrator",
-			  "SELECT COUNT(*)"
+		   "SELECT EXISTS"
+		   "(SELECT *"
 		     " FROM usr_admins"
 		    " WHERE UsrCod=%ld"
 		      " AND Scope='%s'"
-			    " AND Cod=%ld",
+		      " AND Cod=%ld)",
 		   UsrCod,
 		   Sco_GetDBStrFromScope (Scope),
-			  Cod) != 0);
+		   Cod);
   }
 
 /*****************************************************************************/

swad_agenda_database.c

@@ -349,7 +349,6 @@ void Agd_DB_RemoveUsrEvents (long UsrCod)
 
 unsigned Agd_DB_GetNumEventsFromUsr (long UsrCod)
   {
-   /***** Get number of events in a course from database *****/
    return (unsigned)
    DB_QueryCOUNT ("can not get number of events from user",
 		  "SELECT COUNT(*)"

swad_assignment_database.c

@@ -216,15 +216,17 @@ void Asg_DB_GetAssignmentTxtByCod (long AsgCod,char Txt[Cns_MAX_BYTES_TEXT + 1])
 bool Asg_DB_CheckIfSimilarAssignmentExists (const char *Field,const char *Value,
                                             long AsgCod)
   {
-   /***** Get number of assignments with a field value from database *****/
+   return
-   return (DB_QueryCOUNT ("can not get similar assignments",
+   DB_QueryEXISTS ("can not check if similar assignments exist",
-			  "SELECT COUNT(*)"
+		   "SELECT EXISTS"
+		   "(SELECT *"
 		     " FROM asg_assignments"
 		    " WHERE CrsCod=%ld"
 		      " AND %s='%s'"
-			    " AND AsgCod<>%ld",
+		      " AND AsgCod<>%ld)",
 		   Gbl.Hierarchy.Crs.CrsCod,
-			  Field,Value,AsgCod) != 0);
+		   Field,Value,
+		   AsgCod);
   }
 
 /*****************************************************************************/
@@ -309,15 +311,16 @@ void Asg_DB_RemoveAssignment (long AsgCod)
   }
 
 /*****************************************************************************/
-/******************* Get groups associated to an assignment ******************/
+/********************* Check if I can do an assignment ***********************/
 /*****************************************************************************/
 
 bool Asg_DB_CheckIfICanDoAssignment (long AsgCod)
   {
    // Students and teachers can do assignments depending on groups
-   /***** Get if I can do an assignment from database *****/
+   return
-   return (DB_QueryCOUNT ("can not check if I can do an assignment",
+   DB_QueryEXISTS ("can not check if I can do an assignment",
-			  "SELECT COUNT(*)"
+		   "SELECT EXISTS"
+		   "(SELECT *"
 		     " FROM asg_assignments"
 		    " WHERE AsgCod=%ld"
 		      " AND ("
@@ -333,9 +336,9 @@ bool Asg_DB_CheckIfICanDoAssignment (long AsgCod)
 				     "asg_groups"
 			      " WHERE grp_users.UsrCod=%ld"
 				" AND asg_groups.GrpCod=grp_users.GrpCod)"
-				 ")",
+			   "))",
 		   AsgCod,
-			  Gbl.Usrs.Me.UsrDat.UsrCod) != 0);
+		   Gbl.Usrs.Me.UsrDat.UsrCod);
   }
 
 /*****************************************************************************/
@@ -568,7 +571,7 @@ unsigned Asg_DB_GetNumCoursesWithAssignments (HieLvl_Level_t Scope)
                         Gbl.Hierarchy.Crs.CrsCod);
       default:
 	 Err_WrongScopeExit ();
-	 return 0;
+	 return 0;	// Not reached
      }
   }
 

swad_attendance_database.c

@@ -188,17 +188,17 @@ void Att_DB_GetAttEventDescription (long AttCod,char Description[Cns_MAX_BYTES_T
 
 bool Att_DB_CheckIfSimilarAttEventExists (const char *Field,const char *Value,long AttCod)
   {
-   /***** Get number of attendance events
+   return
-          with a field value from database *****/
+   DB_QueryEXISTS ("can not check similar attendance events",
-   return (DB_QueryCOUNT ("can not get similar attendance events",
+		   "SELECT EXISTS"
-			  "SELECT COUNT(*)"
+		   "(SELECT *"
 		     " FROM att_events"
 		    " WHERE CrsCod=%ld"
 		      " AND %s='%s'"
-			    " AND AttCod<>%ld",
+		      " AND AttCod<>%ld)",
 		   Gbl.Hierarchy.Crs.CrsCod,
 		   Field,Value,
-			  AttCod) != 0);
+		   AttCod);
   }
 
 /*****************************************************************************/

swad_banner_database.c

@@ -138,14 +138,15 @@ unsigned Ban_DB_GetDataOfBannerByCod (MYSQL_RES **mysql_res,long BanCod)
 
 bool Ban_DB_CheckIfBannerNameExists (const char *FieldName,const char *Name,long BanCod)
   {
-   /***** Get number of banners with a name from database *****/
+   return
-   return (DB_QueryCOUNT ("can not check if the name of a banner already existed",
+   DB_QueryEXISTS ("can not check if the name of a banner already existed",
-		          "SELECT COUNT(*)"
+		   "SELECT EXISTS"
+		   "(SELECT *"
 		     " FROM ban_banners"
 		    " WHERE %s='%s'"
-			    " AND BanCod<>%ld",
+		      " AND BanCod<>%ld)",
 		   FieldName,Name,
-			  BanCod) != 0);
+		   BanCod);
   }
 
 /*****************************************************************************/

swad_browser_database.c

@@ -1426,19 +1426,20 @@ bool Brw_DB_GetIfFolderHasPublicFiles (const char Path[PATH_MAX + 1])
    long Cod = Brw_GetCodForFileBrowser ();
    long ZoneUsrCod = Brw_GetZoneUsrCodForFileBrowser ();
 
-   /***** Get if a file or folder is public from database *****/
+   return
-   return (DB_QueryCOUNT ("can not check if a folder contains public files",
+   DB_QueryEXISTS ("can not check if a folder contains public files",
-			  "SELECT COUNT(*)"
+		   "SELECT EXISTS"
+		   "(SELECT *"
 		     " FROM brw_files"
 		    " WHERE FileBrowser=%u"
 		      " AND Cod=%ld"
 		      " AND ZoneUsrCod=%ld"
 		      " AND Path LIKE '%s/%%'"
-			    " AND Public='Y'",
+		      " AND Public='Y')",
 		   (unsigned) Brw_DB_FileBrowserForDB_files[Gbl.FileBrowser.Type],
 		   Cod,
 		   ZoneUsrCod,
-			  Path) != 0);
+		   Path);
   }
 
 /*****************************************************************************/
@@ -2325,8 +2326,10 @@ bool Brw_DB_CheckIfFileOrFolderIsSetAsHiddenUsingMetadata (const struct FileMeta
          or
       2) the argument Path begins by 'x/', where x is a path stored in database
    */
-   return (DB_QueryCOUNT ("can not check if a file or folder is hidden",
+   return
-			  "SELECT COUNT(*)"
+   DB_QueryEXISTS ("can not check if a file or folder is hidden",
+		   "SELECT EXISTS"
+		   "(SELECT *"
 		     " FROM brw_files"
 		    " WHERE FileBrowser=%u"
 		      " AND Cod=%ld"
@@ -2334,12 +2337,12 @@ bool Brw_DB_CheckIfFileOrFolderIsSetAsHiddenUsingMetadata (const struct FileMeta
 		      " AND Hidden='Y'"
 		      " AND (Path='%s'"
 			   " OR"
-			         " LOCATE(CONCAT(Path,'/'),'%s')=1)",
+			   " LOCATE(CONCAT(Path,'/'),'%s')=1))",
 		   FileMetadata->FileBrowser,
 		   FileMetadata->Cod,
 		   FileMetadata->ZoneUsrCod,
 		   FileMetadata->FilFolLnk.Full,
-			  FileMetadata->FilFolLnk.Full) != 0);
+		   FileMetadata->FilFolLnk.Full);
   }
 
 /*****************************************************************************/
@@ -2422,42 +2425,48 @@ bool Brw_DB_GetIfExpandedFolder (const char Path[PATH_MAX + 1])
    if (Cod > 0)
      {
       if (WorksUsrCod > 0)
-         return (DB_QueryCOUNT ("can not get check if a folder is expanded",
+	 return
-			        "SELECT COUNT(*)"
+	 DB_QueryEXISTS ("can not check check if a folder is expanded",
+			 "SELECT EXISTS"
+			 "(SELECT *"
 			   " FROM brw_expanded"
 			  " WHERE UsrCod=%ld"
 			    " AND FileBrowser=%u"
 			    " AND Cod=%ld"
 			    " AND WorksUsrCod=%ld"
-				  " AND Path='%s/'",
+			    " AND Path='%s/')",
 			 Gbl.Usrs.Me.UsrDat.UsrCod,
 			 (unsigned) FileBrowserForExpandedFolders,
 			 Cod,
 			 WorksUsrCod,
-			        Path) != 0);
+			 Path);
       else
-         return (DB_QueryCOUNT ("can not get check if a folder is expanded",
+	 return
-				"SELECT COUNT(*)"
+	 DB_QueryEXISTS ("can not get check if a folder is expanded",
+			 "SELECT EXISTS"
+			 "(SELECT *"
 			   " FROM brw_expanded"
 			  " WHERE UsrCod=%ld"
 			    " AND FileBrowser=%u"
 			    " AND Cod=%ld"
-				  " AND Path='%s/'",
+			    " AND Path='%s/')",
 			 Gbl.Usrs.Me.UsrDat.UsrCod,
 			 (unsigned) FileBrowserForExpandedFolders,
 			 Cod,
-				Path) != 0);
+			 Path);
      }
    else	// Briefcase
-      return (DB_QueryCOUNT ("can not get check if a folder is expanded",
+      return
-			     "SELECT COUNT(*)"
+      DB_QueryEXISTS ("can not get check if a folder is expanded",
+		      "SELECT EXISTS"
+		      "(SELECT *"
 			" FROM brw_expanded"
 		       " WHERE UsrCod=%ld"
 			 " AND FileBrowser=%u"
-			       " AND Path='%s/'",
+			 " AND Path='%s/')",
 		      Gbl.Usrs.Me.UsrDat.UsrCod,
 		      (unsigned) FileBrowserForExpandedFolders,
-			     Path) != 0);
+		      Path);
   }
 
 /*****************************************************************************/

swad_building_database.c

@@ -134,16 +134,17 @@ unsigned Bld_DB_GetDataOfBuildingByCod (MYSQL_RES **mysql_res,long BldCod)
 
 bool Bld_DB_CheckIfBuildingNameExists (const char *FieldName,const char *Name,long BldCod)
   {
-   /***** Get number of buildings with a name from database *****/
+   return
-   return (DB_QueryCOUNT ("can not check if the name of a building"
+   DB_QueryEXISTS ("can not check if the name of a building already existed",
-			  " already existed",
+		   "SELECT EXISTS"
-			  "SELECT COUNT(*)"
+		   "(SELECT *"
 		     " FROM bld_buildings"
 		    " WHERE CtrCod=%ld"
 		      " AND %s='%s'"
-			    " AND BldCod<>%ld",
+		      " AND BldCod<>%ld)",
 		   Gbl.Hierarchy.Ctr.CtrCod,
-			  FieldName,Name,BldCod) != 0);
+		   FieldName,Name,
+		   BldCod);
   }
 
 

swad_center_database.c

@@ -306,18 +306,18 @@ unsigned Ctr_DB_GetPhotoAttribution (MYSQL_RES **mysql_res,long CtrCod)
 bool Ctr_DB_CheckIfCtrNameExistsInIns (const char *FieldName,const char *Name,
 				       long CtrCod,long InsCod)
   {
-   /***** Get number of centers with a name from database *****/
+   return
-   return (DB_QueryCOUNT ("can not check if the name of a center"
+   DB_QueryEXISTS ("can not check if the name of a center already existed",
-			  " already existed",
+		   "SELECT EXISTS"
-			  "SELECT COUNT(*)"
+		   "(SELECT *"
 		     " FROM ctr_centers"
 		    " WHERE InsCod=%ld"
 		      " AND %s='%s'"
-			    " AND CtrCod<>%ld",
+		      " AND CtrCod<>%ld)",
 		   InsCod,
 		   FieldName,
 		   Name,
-			  CtrCod) != 0);
+		   CtrCod);
   }
 
 /*****************************************************************************/
@@ -622,33 +622,20 @@ void Ctr_DB_UpdateCtrStatus (long CtrCod,Ctr_Status_t NewStatus)
 /********** Check if any of the centers in an institution has map ************/
 /*****************************************************************************/
 
-bool Ctr_DB_GetIfMapIsAvailableInIns (long InsCod)
+bool Ctr_DB_CheckIfMapIsAvailableInIns (long InsCod)
   {
-   MYSQL_RES *mysql_res;
-   MYSQL_ROW row;
-   bool MapIsAvailable = false;
-
    /***** Get if any center in current institution has a coordinate set
           (coordinates 0, 0 means not set ==> don't show map) *****/
-   if (DB_QuerySELECT (&mysql_res,"can not get if map is available",
+   return
-		       "SELECT EXISTS"	// row[0]
+   DB_QueryEXISTS ("can not check if map is available",
+		   "SELECT EXISTS"
 		   "(SELECT *"
 		     " FROM ctr_centers"
 		    " WHERE InsCod=%ld"
 		      " AND (Latitude<>0"
 			   " OR"
 			   " Longitude<>0))",
-		       InsCod))
+		   InsCod);
-     {
-      /* Get if map is available */
-      row = mysql_fetch_row (mysql_res);
-      MapIsAvailable = (row[0][0] == '1');
-     }
-
-   /* Free structure that stores the query result */
-   DB_FreeMySQLResult (&mysql_res);
-
-   return MapIsAvailable;
   }
 
 /*****************************************************************************/

swad_center_database.h

@@ -81,7 +81,7 @@ void Ctr_DB_UpdateCtrCoordinate (long CtrCod,
 void Ctr_DB_UpdateCtrStatus (long CtrCod,Ctr_Status_t NewStatus);
 
 
-bool Ctr_DB_GetIfMapIsAvailableInIns (long InsCod);
+bool Ctr_DB_CheckIfMapIsAvailableInIns (long InsCod);
 void Ctr_DB_GetCoordAndZoom (struct Map_Coordinates *Coord,unsigned *Zoom);
 void Ctr_DB_GetCoordAndZoomInCurrentIns (struct Map_Coordinates *Coord,unsigned *Zoom);
 unsigned Ctr_DB_GetCtrsWithCoords (MYSQL_RES **mysql_res);

swad_changelog.h

@@ -602,13 +602,14 @@ TODO: FIX BUG, URGENT! En las fechas como par
 
 TODO: En las encuestas, que los estudiantes no puedan ver los resultados hasta que no finalice el plazo.
 */
-#define Log_PLATFORM_VERSION	"SWAD 21.51 (2021-11-04)"
+#define Log_PLATFORM_VERSION	"SWAD 21.52 (2021-11-05)"
 #define CSS_FILE		"swad20.45.css"
 #define JS_FILE			"swad20.69.1.js"
 /*
 TODO: Rename CENTRE to CENTER in help wiki.
 TODO: Rename ASSESSMENT.Announcements to ASSESSMENT.Calls_for_exams
 
+	Version 21.52:    Nov 05, 2021  Changed SELECT COUNT to SELECT EXISTS in some queries. (321833 lines)
 	Version 21.51:    Nov 04, 2021  Eliminated the limit of origin courses in messages. (321735 lines)
 	Version 21.50.1:  Nov 03, 2021  Queries moved to module swad_user_database and other modules. (321759 lines)
 	Version 21.50:    Nov 03, 2021  Queries moved to module swad_user_database and other modules. (321696 lines)

swad_connected_database.c

@@ -47,12 +47,11 @@ extern struct Globals Gbl;
 /*****************************************************************************/
 
 /*****************************************************************************/
-/********************* Get connected users with a role ***********************/
+/**************** Get number of connected users with a role ******************/
 /*****************************************************************************/
 
 unsigned Con_DB_GetConnectedUsrsTotal (Rol_Role_t Role)
   {
-   /***** Get number of connected users with a role from database *****/
    return (unsigned)
    DB_QueryCOUNT ("can not get number of connected users",
 		  "SELECT COUNT(*)"

swad_country.c

@@ -1879,7 +1879,7 @@ static void Cty_FormToGoToMap (struct Cty_Countr *Cty)
   {
    extern const char *Txt_Map;
 
-   if (Cty_DB_GetIfMapIsAvailable (Cty->CtyCod))
+   if (Cty_DB_CheckIfMapIsAvailable (Cty->CtyCod))
      {
       Cty_EditingCty = Cty;	// Used to pass parameter with the code of the country
       Lay_PutContextualLinkOnlyIcon (ActSeeCtyInf,NULL,

swad_country_database.c

@@ -374,13 +374,13 @@ unsigned Cty_DB_GetNumCtysWithUsrs (Rol_Role_t Role,
 
 bool Cty_DB_CheckIfNumericCountryCodeExists (long CtyCod)
   {
-   /***** Get number of countries with a name from database *****/
+   return
-   return (DB_QueryCOUNT ("can not check if the numeric code"
+   DB_QueryEXISTS ("can not check if the numeric code of a country already existed",
-	                  " of a country already existed",
+		   "SELECT EXISTS"
-			  "SELECT COUNT(*)"
+		   "(SELECT *"
 		     " FROM cty_countrs"
-			  " WHERE CtyCod='%03ld'",
+		    " WHERE CtyCod='%03ld')",
-			  CtyCod) != 0);
+		   CtyCod);
   }
 
 /*****************************************************************************/
@@ -389,13 +389,13 @@ bool Cty_DB_CheckIfNumericCountryCodeExists (long CtyCod)
 
 bool Cty_DB_CheckIfAlpha2CountryCodeExists (const char Alpha2[2 + 1])
   {
-   /***** Get number of countries with a name from database *****/
+   return
-   return (DB_QueryCOUNT ("can not check if the alphabetic code"
+   DB_QueryEXISTS ("can not check if the alphabetic code of a country already existed",
-	                  " of a country already existed",
+		   "SELECT EXISTS"
-			  "SELECT COUNT(*)"
+		   "(SELECT *"
 		     " FROM cty_countrs"
-			  " WHERE Alpha2='%s'",
+		    " WHERE Alpha2='%s')",
-			  Alpha2) != 0);
+		   Alpha2);
   }
 
 /*****************************************************************************/
@@ -406,15 +406,15 @@ bool Cty_DB_CheckIfCountryNameExists (Lan_Language_t Language,const char *Name,l
   {
    extern const char *Lan_STR_LANG_ID[1 + Lan_NUM_LANGUAGES];
 
-   /***** Get number of countries with a name from database *****/
+   return
-   return (DB_QueryCOUNT ("can not check if the name"
+   DB_QueryEXISTS ("can not check if the name of a country already existed",
-	                  " of a country already existed",
+		   "SELECT EXISTS"
-			  "SELECT COUNT(*)"
+		   "(SELECT *"
 		     " FROM cty_countrs"
 		    " WHERE Name_%s='%s'"
-			    " AND CtyCod<>'%03ld'",
+		      " AND CtyCod<>'%03ld')",
 		   Lan_STR_LANG_ID[Language],Name,
-			  CtyCod) != 0);
+		   CtyCod);
   }
 
 /*****************************************************************************/
@@ -504,15 +504,12 @@ unsigned Cty_DB_GetMapAttr (MYSQL_RES **mysql_res,long CtyCod)
 /************ Check if any of the centers in a country has map ***************/
 /*****************************************************************************/
 
-bool Cty_DB_GetIfMapIsAvailable (long CtyCod)
+bool Cty_DB_CheckIfMapIsAvailable (long CtyCod)
   {
-   MYSQL_RES *mysql_res;
+   /***** Check if any center in current country has a coordinate set
-   MYSQL_ROW row;
-   bool MapIsAvailable = false;
-
-   /***** Get if any center in current country has a coordinate set
           (coordinates 0, 0 means not set ==> don't show map) *****/
-   if (DB_QuerySELECT (&mysql_res,"can not get if map is available",
+   return
+   DB_QueryEXISTS ("can not check if map is available",
 		   "SELECT EXISTS"
 		   "(SELECT *"
 		    " FROM ins_instits,"
@@ -521,17 +518,7 @@ bool Cty_DB_GetIfMapIsAvailable (long CtyCod)
 		     " AND ins_instits.InsCod=ctr_centers.InsCod"
 		     " AND (ctr_centers.Latitude<>0"
 		       " OR ctr_centers.Longitude<>0))",
-		       CtyCod))
+		   CtyCod);
-     {
-      /* Get if map is available */
-      row = mysql_fetch_row (mysql_res);
-      MapIsAvailable = (row[0][0] == '1');
-     }
-
-   /* Free structure that stores the query result */
-   DB_FreeMySQLResult (&mysql_res);
-
-   return MapIsAvailable;
   }
 
 /*****************************************************************************/

swad_country_database.h

@@ -69,7 +69,7 @@ unsigned Cty_DB_SearchCtys (MYSQL_RES **mysql_res,
 void Cty_DB_GetCoordAndZoom (struct Map_Coordinates *Coord,unsigned *Zoom);
 unsigned Cty_DB_GetCtrsWithCoordsInCurrentCty (MYSQL_RES **mysql_res);
 unsigned Cty_DB_GetMapAttr (MYSQL_RES **mysql_res,long CtyCod);
-bool Cty_DB_GetIfMapIsAvailable (long CtyCod);
+bool Cty_DB_CheckIfMapIsAvailable (long CtyCod);
 
 void Cty_DB_UpdateCtyField (long CtyCod,const char *FieldName,const char *FieldValue);
 void Cty_DB_UpdateCtyMapAttr (const char NewMapAttribution[Med_MAX_BYTES_ATTRIBUTION + 1]);

swad_course_database.c

@@ -202,20 +202,20 @@ void Crs_DB_GetShortNamesByCod (long CrsCod,
 bool Crs_DB_CheckIfCrsNameExistsInYearOfDeg (const char *FieldName,const char *Name,long CrsCod,
                                              long DegCod,unsigned Year)
   {
-   /***** Get number of courses in a year of a degree and with a name from database *****/
+   return
-   return (DB_QueryCOUNT ("can not check if the name"
+   DB_QueryEXISTS ("can not check if the name of a course already existed",
-	                  " of a course already existed",
+		   "SELECT EXISTS"
-			  "SELECT COUNT(*)"
+		   "(SELECT *"
 		     " FROM crs_courses"
 		    " WHERE DegCod=%ld"
 		      " AND Year=%u"
 		      " AND %s='%s'"
-			   " AND CrsCod<>%ld",
+		      " AND CrsCod<>%ld)",
 		   DegCod,
 		   Year,
 		   FieldName,
 		   Name,
-			  CrsCod) != 0);
+		   CrsCod);
   }
 
 /*****************************************************************************/

swad_database.c

@@ -4077,6 +4077,34 @@ unsigned long DB_QueryCOUNT (const char *MsgError,const char *fmt,...)
    return NumRows;
   }
 
+bool DB_QueryEXISTS (const char *MsgError,const char *fmt,...)
+  {
+   va_list ap;
+   int NumBytesPrinted;
+   char *Query;
+   MYSQL_RES *mysql_res;
+   MYSQL_ROW row;
+   bool Exists = false;
+
+   va_start (ap,fmt);
+   NumBytesPrinted = vasprintf (&Query,fmt,ap);
+   va_end (ap);
+   if (NumBytesPrinted < 0)	// -1 if no memory or any other error
+      Err_NotEnoughMemoryExit ();
+
+   /***** Make query "SELECT EXISTS (...)" *****/
+   if (DB_QuerySELECTusingQueryStr (Query,&mysql_res,MsgError))
+     {
+      row = mysql_fetch_row (mysql_res);
+      Exists = (row[0][0] == '1');
+     }
+
+   /***** Free structure that stores the query result *****/
+   DB_FreeMySQLResult (&mysql_res);
+
+   return Exists;
+  }
+
 /*****************************************************************************/
 /******************** Make an INSERT query in database ***********************/
 /*****************************************************************************/

swad_database.h

@@ -57,6 +57,7 @@ void DB_QuerySELECTString (char *Str,size_t StrSize,const char *MsgError,
 long DB_GetNextCode (MYSQL_RES *mysql_res);
 unsigned long DB_GetNumRowsTable (const char *Table);
 unsigned long DB_QueryCOUNT (const char *MsgError,const char *fmt,...);
+bool DB_QueryEXISTS (const char *MsgError,const char *fmt,...);
 
 void DB_QueryINSERT (const char *MsgError,const char *fmt,...);
 

swad_degree_database.c

@@ -305,14 +305,15 @@ void Deg_DB_GetShortNameOfDegreeByCod (long DegCod,char ShrtName[Cns_HIERARCHY_M
 
 bool Deg_DB_CheckIfDegreeTypeNameExists (const char *DegTypName,long DegTypCod)
   {
-   /***** Get number of degree types with a name from database *****/
+   return
-   return (DB_QueryCOUNT ("can not check if the name of a type of degree"
+   DB_QueryEXISTS ("can not check if the name of a type of degree already existed",
-			  " already existed",
+		   "SELECT EXISTS"
-			  "SELECT COUNT(*)"
+		   "(SELECT *"
 		     " FROM deg_types"
 		    " WHERE DegTypName='%s'"
-			    " AND DegTypCod<>%ld",
+		      " AND DegTypCod<>%ld)",
-			  DegTypName,DegTypCod) != 0);
+		   DegTypName,
+		   DegTypCod);
   }
 
 /*****************************************************************************/
@@ -460,17 +461,17 @@ unsigned Deg_DB_GetDegsWithStds (MYSQL_RES **mysql_res)
 bool Deg_DB_CheckIfDegNameExistsInCtr (const char *FieldName,const char *Name,
                                        long DegCod,long CtrCod)
   {
-   /***** Get number of degrees with a type and a name from database *****/
+   return
-   return (DB_QueryCOUNT ("can not check if the name of a degree"
+   DB_QueryEXISTS ("can not check if the name of a degree already existed",
-			  " already existed",
+		   "SELECT EXISTS"
-			  "SELECT COUNT(*)"
+		   "(SELECT *"
 		     " FROM deg_degrees"
 		    " WHERE CtrCod=%ld"
 		      " AND %s='%s'"
-			    " AND DegCod<>%ld",
+		      " AND DegCod<>%ld)",
 		   CtrCod,
 		   FieldName,Name,
-			  DegCod) != 0);
+		   DegCod);
   }
 
 /*****************************************************************************/
@@ -549,7 +550,8 @@ unsigned Deg_DB_GetNumDegsWithUsrs (Rol_Role_t Role,
 		    " AND deg_degrees.DegCod=crs_courses.DegCod"
 		    " AND crs_courses.CrsCod=crs_users.CrsCod"
 		    " AND crs_users.Role=%u",
-		  SubQuery,(unsigned) Role);
+		  SubQuery,
+		  (unsigned) Role);
   }
 
 /*****************************************************************************/
@@ -761,16 +763,18 @@ unsigned Deg_DB_GetUsrMainDeg (MYSQL_RES **mysql_res,long UsrCod)
 
 bool Deg_DB_CheckIfUsrBelongsToDeg (long UsrCod,long DegCod)
   {
-   return (DB_QueryCOUNT ("can not check if a user belongs to a degree",
+   return
-			  "SELECT COUNT(DISTINCT crs_courses.DegCod)"
+   DB_QueryEXISTS ("can not check if a user belongs to a degree",
+		   "SELECT EXISTS"
+		   "(SELECT *"
 		     " FROM crs_users,"
 			   "crs_courses"
 		    " WHERE crs_users.UsrCod=%ld"
 		      " AND crs_users.Accepted='Y'"	// Only if user accepted
 		      " AND crs_users.CrsCod=crs_courses.CrsCod"
-			    " AND crs_courses.DegCod=%ld",
+		      " AND crs_courses.DegCod=%ld)",
 		   UsrCod,
-			  DegCod) != 0);
+		   DegCod);
   }
 
 /*****************************************************************************/

swad_department_database.c

@@ -164,14 +164,15 @@ unsigned Dpt_DB_GetDataOfDepartmentByCod (MYSQL_RES **mysql_res,long DptCod)
 
 bool Dpt_DB_CheckIfDepartmentNameExists (const char *FieldName,const char *Name,long DptCod)
   {
-   /***** Get number of departments with a name from database *****/
+   return
-   return (DB_QueryCOUNT ("can not check if the department name already existed",
+   DB_QueryEXISTS ("can not check if the department name already existed",
-			  "SELECT COUNT(*)"
+		   "SELECT EXISTS"
+		   "(SELECT *"
 		     " FROM dpt_departments"
 		    " WHERE %s='%s'"
-			    " AND DptCod<>%ld",
+		      " AND DptCod<>%ld)",
 		   FieldName,Name,
-			  DptCod) != 0);
+		   DptCod);
   }
 
 /*****************************************************************************/

swad_duplicate_database.c

@@ -117,12 +117,13 @@ unsigned Dup_DB_GetUsrsSimilarTo (MYSQL_RES **mysql_res,const struct UsrData *Us
 
 bool Dup_DB_CheckIfUsrIsDup (long UsrCod)
   {
-   return (DB_QueryCOUNT ("can not if user is in list"
+   return
-			  " of possible duplicate users",
+   DB_QueryEXISTS ("can not check if user is in list of possible duplicate users",
-			  "SELECT COUNT(*)"
+		   "SELECT EXISTS"
+		   "(SELECT *"
 		     " FROM usr_duplicated"
-			  " WHERE UsrCod=%ld",
+		    " WHERE UsrCod=%ld)",
-			  UsrCod) != 0);
+		   UsrCod);
   }
 
 /*****************************************************************************/

swad_enrolment_database.c

@@ -152,15 +152,17 @@ bool Enr_DB_CheckIfUsrBelongsToCrs (long UsrCod,long CrsCod,
    const char *SubQuery = (CountOnlyAcceptedCourses ? " AND crs_users.Accepted='Y'" :	// Only if user accepted
 	                                              "");
 
-   return (DB_QueryCOUNT ("can not check if a user belongs to a course",
+   return
-			  "SELECT COUNT(*)"
+   DB_QueryEXISTS ("can not check if a user belongs to a course",
+		   "SELECT EXISTS"
+		   "(SELECT *"
 		     " FROM crs_users"
 		    " WHERE CrsCod=%ld"
 		      " AND UsrCod=%ld"
-			      "%s",
+			"%s)",
 		   CrsCod,
 		   UsrCod,
-			  SubQuery) != 0);
+		   SubQuery);
   }
 
 /*****************************************************************************/
@@ -173,14 +175,16 @@ bool Enr_DB_CheckIfUsrSharesAnyOfMyCrs (long UsrCod)
    Enr_GetMyCourses ();
 
    /* Check if user shares any course with me */
-   return (DB_QueryCOUNT ("can not check if a user shares any course with you",
+   return
-			  "SELECT COUNT(*)"
+   DB_QueryEXISTS ("can not check if a user shares any course with you",
+		   "SELECT EXISTS"
+		   "(SELECT *"
 		     " FROM crs_users"
 		    " WHERE UsrCod=%ld"
 		      " AND CrsCod IN"
 			  " (SELECT CrsCod"
-				   " FROM my_courses_tmp)",
+			     " FROM my_courses_tmp))",
-			  UsrCod) != 0);
+		   UsrCod);
   }
 
 /*****************************************************************************/
@@ -217,12 +221,13 @@ bool Enr_DB_CheckIfUsrSharesAnyOfMyCrsWithDifferentRole (long UsrCod)
 
    /* Get if a user shares any course with me from database */
    UsrSharesAnyOfMyCrsWithDifferentRole =
-      (DB_QueryCOUNT ("can not check if a user shares any course with you",
+   DB_QueryEXISTS ("can not check if a user shares any course with you",
-		      "SELECT COUNT(*)"
+		   "SELECT EXISTS"
+		   "(SELECT *"
 		     " FROM my_courses_tmp,"
 			   "usr_courses_tmp"
 		    " WHERE my_courses_tmp.CrsCod=usr_courses_tmp.CrsCod"
-                        " AND my_courses_tmp.Role<>usr_courses_tmp.Role") != 0);
+		      " AND my_courses_tmp.Role<>usr_courses_tmp.Role)");
 
    /* Remove temporary table if exists */
    DB_Query ("can not remove temporary tables",

swad_exam_database.c

@@ -243,15 +243,17 @@ void Exa_DB_GetExamTxt (long ExaCod,char Txt[Cns_MAX_BYTES_TEXT + 1])
 
 bool Exa_DB_CheckIfSimilarExamExists (long CrsCod,long ExaCod,const char *Title)
   {
-   return (DB_QueryCOUNT ("can not get similar exams",
+   return
-			  "SELECT COUNT(*)"
+   DB_QueryEXISTS ("can not check similar exams",
+		   "SELECT EXISTS"
+		   "(SELECT *"
 		     " FROM exa_exams"
 		    " WHERE CrsCod=%ld"
 		      " AND Title='%s'"
-			    " AND ExaCod<>%ld",
+		      " AND ExaCod<>%ld)",
 		   CrsCod,
 		   Title,
-			  ExaCod) != 0);
+		   ExaCod);
   }
 
 /*****************************************************************************/
@@ -708,19 +710,20 @@ unsigned Exa_DB_GetDataOfSetByCod (MYSQL_RES **mysql_res,long SetCod)
 bool Exa_DB_CheckIfSimilarSetExists (const struct ExaSet_Set *Set,
                                      const char Title[ExaSet_MAX_BYTES_TITLE + 1])
   {
-   /***** Get number of set of questions with a field value from database *****/
+   return
-   return (DB_QueryCOUNT ("can not get similar sets of questions",
+   DB_QueryEXISTS ("can not check similar sets of questions",
-			  "SELECT COUNT(*)"
+		   "SELECT EXISTS"
+		   "(SELECT *"
 		     " FROM exa_sets,"
 			   "exa_exams"
 		    " WHERE exa_sets.ExaCod=%ld"
 		      " AND exa_sets.Title='%s'"
 		      " AND exa_sets.SetCod<>%ld"
 		      " AND exa_sets.ExaCod=exa_exams.ExaCod"
-			    " AND exa_exams.CrsCod=%ld",	// Extra check
+		      " AND exa_exams.CrsCod=%ld)",	// Extra check
 		   Set->ExaCod,Title,
 		   Set->SetCod,
-			  Gbl.Hierarchy.Crs.CrsCod) != 0);
+		   Gbl.Hierarchy.Crs.CrsCod);
   }
 
 /*****************************************************************************/
@@ -1668,8 +1671,10 @@ unsigned Exa_DB_GetGrpsAssociatedToSes (MYSQL_RES **mysql_res,long SesCod)
 
 bool Exa_DB_CheckIfICanListThisSessionBasedOnGrps (long SesCod)
   {
-   return (DB_QueryCOUNT ("can not check if I can play an exam session",
+   return
-			  "SELECT COUNT(*)"
+   DB_QueryEXISTS ("can not check if I can play an exam session",
+		   "SELECT EXISTS"
+		   "(SELECT *"
 		     " FROM exa_sessions"
 		    " WHERE SesCod=%ld"
 		      " AND (SesCod NOT IN"
@@ -1680,9 +1685,9 @@ bool Exa_DB_CheckIfICanListThisSessionBasedOnGrps (long SesCod)
 			      " FROM exa_groups,"
 				    "grp_users"
 			     " WHERE grp_users.UsrCod=%ld"
-				   " AND grp_users.GrpCod=exa_groups.GrpCod))",
+			       " AND grp_users.GrpCod=exa_groups.GrpCod)))",
 		   SesCod,
-			  Gbl.Usrs.Me.UsrDat.UsrCod) != 0);
+		   Gbl.Usrs.Me.UsrDat.UsrCod);
   }
 
 /*****************************************************************************/
@@ -2106,18 +2111,18 @@ void Exa_DB_RemovePrintQstsFromCrs (long CrsCod)
 
 bool Exa_DB_CheckIfSessionIsTheSameAsTheLast (long PrnCod)
   {
-   /***** Check if the current session id
+   return
-          is the same as the last one stored in database *****/
+   DB_QueryEXISTS ("can not check session",
-   return (DB_QueryCOUNT ("can not check session",
+		   "SELECT EXISTS"
-			  "SELECT COUNT(*)"
+		   "(SELECT *"
 		     " FROM exa_log_sessions"
 		    " WHERE LogCod="
 			   "(SELECT MAX(LogCod)"
 			     " FROM exa_log_sessions"
 			    " WHERE PrnCod=%ld)"
-			    " AND SessionId='%s'",
+		      " AND SessionId='%s')",
 		   PrnCod,
-			  Gbl.Session.Id) != 0);
+		   Gbl.Session.Id);
   }
 
 /*****************************************************************************/
@@ -2126,18 +2131,18 @@ bool Exa_DB_CheckIfSessionIsTheSameAsTheLast (long PrnCod)
 
 bool Exa_DB_CheckIfUserAgentIsTheSameAsTheLast (long PrnCod,const char *UserAgentDB)
   {
-   /***** Get if the current user agent
+   return
-          is the same as the last stored in database *****/
+   DB_QueryEXISTS ("can not check user agent",
-   return (DB_QueryCOUNT ("can not check user agent",
+		   "SELECT EXISTS"
-			  "SELECT COUNT(*)"
+		   "(SELECT *"
 		     " FROM exa_log_user_agents"
 		    " WHERE LogCod="
 			   "(SELECT MAX(LogCod)"
 			     " FROM exa_log_user_agents"
 			    " WHERE PrnCod=%ld)"
-			    " AND UserAgent='%s'",
+		      " AND UserAgent='%s')",
 		   PrnCod,
-			  UserAgentDB) != 0);
+		   UserAgentDB);
   }
 
 /*****************************************************************************/

swad_follow_database.c

@@ -239,12 +239,15 @@ bool Fol_DB_CheckUsrIsFollowerOf (long FollowerCod,long FollowedCod)
       return false;
 
    /***** Check if a user is a follower of another user *****/
-   return (DB_QueryCOUNT ("can not get if a user is a follower of another one",
+   return
-			  "SELECT COUNT(*)"
+   DB_QueryEXISTS ("can not check if a user is a follower of another one",
+		   "SELECT EXISTS"
+		   "(SELECT *"
 		     " FROM usr_follow"
 		    " WHERE FollowerCod=%ld"
-			    " AND FollowedCod=%ld",
+		      " AND FollowedCod=%ld)",
-			  FollowerCod,FollowedCod) != 0);
+		   FollowerCod,
+		   FollowedCod);
   }
 
 /*****************************************************************************/

swad_forum.c

@@ -451,7 +451,7 @@ void For_DisablePost (void)
    For_GetParamsForums (&Forums);
 
    /***** Check if post really exists, if it has not been removed *****/
-   if (For_DB_GetIfForumPstExists (Forums.PstCod))
+   if (For_DB_CheckIfForumPstExists (Forums.PstCod))
      {
       /***** Insert post into table of banned posts *****/
       For_DB_InsertPstIntoDisabled (Forums.PstCod);
@@ -2890,7 +2890,7 @@ void For_RemovePost (void)
 
    /***** Check if I can remove the post *****/
    /* Check if the message really exists, if it has not been removed */
-   if (!For_DB_GetIfForumPstExists (Forums.PstCod))
+   if (!For_DB_CheckIfForumPstExists (Forums.PstCod))
       Err_WrongPostExit ();
 
    /* Check if I am the author of the message */

swad_forum_database.c

@@ -257,13 +257,15 @@ void For_DB_UpdateNumUsrsNotifiedByEMailAboutPost (long PstCod,
 /******************** Get if a forum post exists in database *****************/
 /*****************************************************************************/
 
-bool For_DB_GetIfForumPstExists (long PstCod)
+bool For_DB_CheckIfForumPstExists (long PstCod)
   {
-   return (DB_QueryCOUNT ("can not check if a post of a forum already existed",
+   return
-			  "SELECT COUNT(*)"
+   DB_QueryEXISTS ("can not check if a post of a forum already existed",
+		   "SELECT EXISTS"
+		   "(SELECT *"
 		     " FROM for_posts"
-			  " WHERE PstCod=%ld",
+		    " WHERE PstCod=%ld)",
-			  PstCod) != 0);	// Post exists if it appears in table of forum posts
+		   PstCod);	// Post exists if it appears in table of forum posts
   }
 
 /*****************************************************************************/
@@ -542,15 +544,17 @@ bool For_DB_CheckIfThrBelongsToForum (long ThrCod,const struct For_Forum *Forum)
    else
       SubQuery[0] = '\0';
 
-   return (DB_QueryCOUNT ("can not get if a thread belong to current forum",
+   return
-			  "SELECT COUNT(*)"
+   DB_QueryEXISTS ("can not check if a thread belong to current forum",
+		   "SELECT EXISTS"
+		   "(SELECT *"
 		     " FROM for_threads"
 		    " WHERE ThrCod=%ld"
 		      " AND ForumType=%u"
-			    "%s",
+		        "%s)",
 		   ThrCod,
 		   (unsigned) Forum->Type,
-			  SubQuery) != 0);
+		   SubQuery);
   }
 
 /*****************************************************************************/
@@ -627,7 +631,6 @@ unsigned For_DB_GetNumPstsInThr (long ThrCod)
 
 unsigned For_DB_GetNumMyPstsInThr (long ThrCod)
   {
-   /***** Get if I have write posts in a thread from database *****/
    return (unsigned)
    DB_QueryCOUNT ("can not check if you have written posts in a thead of a forum",
 		  "SELECT COUNT(*)"
@@ -696,7 +699,6 @@ void For_DB_UpdateThrReadTime (long ThrCod,
 
 unsigned For_DB_GetNumReadersOfThr (long ThrCod)
   {
-   /***** Get number of distinct readers of a thread from database *****/
    return (unsigned)
    DB_QueryCOUNT ("can not get the number of readers of a thread of a forum",
 		  "SELECT COUNT(*)"
@@ -954,11 +956,13 @@ bool For_DB_GetIfPstIsEnabled (long PstCod)
       return false;
 
    /***** Get if post is disabled from database *****/
-   return (DB_QueryCOUNT ("can not check if a post of a forum is disabled",
+   return
-			  "SELECT COUNT(*)"
+   DB_QueryEXISTS ("can not check if a post of a forum is disabled",
+		   "SELECT EXISTS"
+		   "(SELECT *"
 		     " FROM for_disabled"
-			  " WHERE PstCod=%ld",
+		    " WHERE PstCod=%ld)",
-			  PstCod) == 0);	// Post is enabled if it does not appear in table of disabled posts
+		   PstCod);	// Post is enabled if it does not appear in table of disabled posts
   }
 
 /*****************************************************************************/

swad_forum_database.h

@@ -51,7 +51,7 @@ long For_DB_InsertForumPst (long ThrCod,long UsrCod,
                             long MedCod);
 void For_DB_UpdateNumUsrsNotifiedByEMailAboutPost (long PstCod,
                                                    unsigned NumUsrsToBeNotifiedByEMail);
-bool For_DB_GetIfForumPstExists (long PstCod);
+bool For_DB_CheckIfForumPstExists (long PstCod);
 unsigned For_DB_GetPstData (MYSQL_RES **mysql_res,long PstCod);
 unsigned For_DB_GetPstSubjectAndContent (MYSQL_RES **mysql_res,long PstCod);
 unsigned For_DB_GetForumTypeAndLocationOfAPost (MYSQL_RES **mysql_res,long PstCod);

swad_game_database.c

@@ -231,15 +231,17 @@ void Gam_DB_GetGameTxt (long GamCod,char Txt[Cns_MAX_BYTES_TEXT + 1])
 
 bool Gam_DB_CheckIfSimilarGameExists (const struct Gam_Game *Game)
   {
-   return (DB_QueryCOUNT ("can not get similar games",
+   return
-			  "SELECT COUNT(*)"
+   DB_QueryEXISTS ("can not check similar games",
+		   "SELECT EXISTS"
+		   "(SELECT *"
 		     " FROM gam_games"
 		    " WHERE CrsCod=%ld"
 		      " AND Title='%s'"
-			    " AND GamCod<>%ld",
+		      " AND GamCod<>%ld)",
 		   Gbl.Hierarchy.Crs.CrsCod,
 		   Game->Title,
-			  Game->GamCod) != 0);
+		   Game->GamCod);
   }
 
 /*****************************************************************************/

swad_group_database.c

@@ -196,11 +196,13 @@ unsigned Grp_DB_GetDataOfGroupByCod (MYSQL_RES **mysql_res,long GrpCod)
 
 bool Grp_DB_CheckIfGrpExists (long GrpCod)
   {
-   return (DB_QueryCOUNT ("can not check if a group exists",
+   return
-			  "SELECT COUNT(*)"
+   DB_QueryEXISTS ("can not check if a group exists",
+		   "SELECT EXISTS"
+		   "(SELECT *"
 		     " FROM grp_groups"
-			  " WHERE GrpCod=%ld",
+		    " WHERE GrpCod=%ld)",
-			  GrpCod) != 0);
+		   GrpCod);
   }
 
 /*****************************************************************************/
@@ -209,15 +211,16 @@ bool Grp_DB_CheckIfGrpExists (long GrpCod)
 
 bool Grp_DB_CheckIfGrpBelongsToCrs (long GrpCod,long CrsCod)
   {
-   /***** Get if a group exists from database *****/
+   return
-   return (DB_QueryCOUNT ("can not check if a group belongs to a course",
+   DB_QueryEXISTS ("can not check if a group belongs to a course",
-			  "SELECT COUNT(*)"
+		   "SELECT EXISTS"
+		   "(SELECT *"
 		     " FROM grp_groups,"
 			   "grp_types"
 		    " WHERE grp_groups.GrpCod=%ld"
 		      " AND grp_groups.GrpTypCod=grp_types.GrpTypCod"
-			    " AND grp_types.CrsCod=%ld",
+		      " AND grp_types.CrsCod=%ld)",
-			  GrpCod,CrsCod) != 0);
+		   GrpCod,CrsCod);
   }
 
 /*****************************************************************************/
@@ -226,17 +229,17 @@ bool Grp_DB_CheckIfGrpBelongsToCrs (long GrpCod,long CrsCod)
 
 bool Grp_DB_CheckIfGrpTypNameExistsInCurrentCrs (const char *GrpTypName,long GrpTypCod)
   {
-   /***** Get number of group types with a name from database *****/
+   return
-   return (DB_QueryCOUNT ("can not check if the name of type of group"
+   DB_QueryEXISTS ("can not check if the name of type of group already existed",
-			  " already existed",
+		   "SELECT EXISTS"
-			  "SELECT COUNT(*)"
+		   "(SELECT *"
 		     " FROM grp_types"
 		    " WHERE CrsCod=%ld"
 		      " AND GrpTypName='%s'"
-			    " AND GrpTypCod<>%ld",
+		      " AND GrpTypCod<>%ld)",
 		   Gbl.Hierarchy.Crs.CrsCod,
 		   GrpTypName,
-			  GrpTypCod) != 0);
+		   GrpTypCod);
   }
 
 /*****************************************************************************/
@@ -245,16 +248,17 @@ bool Grp_DB_CheckIfGrpTypNameExistsInCurrentCrs (const char *GrpTypName,long Grp
 
 bool Grp_DB_CheckIfGrpNameExistsForGrpTyp (long GrpTypCod,const char *GrpName,long GrpCod)
   {
-   /***** Get number of groups with a type and a name from database *****/
+   return
-   return (DB_QueryCOUNT ("can not check if the name of group already existed",
+   DB_QueryEXISTS ("can not check if the name of group already existed",
-			  "SELECT COUNT(*)"
+		   "SELECT EXISTS"
+		   "(SELECT *"
 		     " FROM grp_groups"
 		    " WHERE GrpTypCod=%ld"
 		      " AND GrpName='%s'"
-			    " AND GrpCod<>%ld",
+		      " AND GrpCod<>%ld)",
 		   GrpTypCod,
 		   GrpName,
-			  GrpCod) != 0);
+		   GrpCod);
   }
 
 /*****************************************************************************/
@@ -372,15 +376,17 @@ unsigned Grp_DB_GetTchsFromCurrentGrpExceptMe (MYSQL_RES **mysql_res)
 
 bool Grp_DB_CheckIfIBelongToGrpsOfType (long GrpTypCod)
   {
-   return (DB_QueryCOUNT ("can not check if you belong to a group type",
+   return
-			  "SELECT COUNT(grp_groups.GrpCod)"
+   DB_QueryEXISTS ("can not check if you belong to a group type",
+		   "SELECT EXISTS"
+		   "(SELECT *"
 		     " FROM grp_groups,"
 			   "grp_users"
 		    " WHERE grp_groups.GrpTypCod=%ld"
 		      " AND grp_groups.GrpCod=grp_users.GrpCod"
-			    " AND grp_users.UsrCod=%ld",	// I belong
+		      " AND grp_users.UsrCod=%ld)",	// I belong
 		   GrpTypCod,
-			  Gbl.Usrs.Me.UsrDat.UsrCod) != 0);
+		   Gbl.Usrs.Me.UsrDat.UsrCod);
   }
 
 /*****************************************************************************/
@@ -389,25 +395,27 @@ bool Grp_DB_CheckIfIBelongToGrpsOfType (long GrpTypCod)
 
 bool Grp_DB_CheckIfIBelongToGrp (long GrpCod)
   {
-   return (DB_QueryCOUNT ("can not check if you belong to a group",
+   return
-			  "SELECT COUNT(*)"
+   DB_QueryEXISTS ("can not check if you belong to a group",
+		   "SELECT EXISTS"
+		   "(SELECT *"
 		     " FROM grp_users"
 		    " WHERE GrpCod=%ld"
-			    " AND UsrCod=%ld",			// I belong
+		      " AND UsrCod=%ld)",	// I belong
 		   GrpCod,
-			  Gbl.Usrs.Me.UsrDat.UsrCod) != 0);
+		   Gbl.Usrs.Me.UsrDat.UsrCod);
   }
 
 /*****************************************************************************/
 /***** Check if a user belongs to any of my groups in the current course *****/
 /*****************************************************************************/
 
-unsigned Grp_DB_CheckIfUsrSharesAnyOfMyGrpsInCurrentCrs (long UsrCod)
+bool Grp_DB_CheckIfUsrSharesAnyOfMyGrpsInCurrentCrs (long UsrCod)
   {
-   return (unsigned)
+   return
-   (DB_QueryCOUNT ("can not check if a user shares any group"
+   DB_QueryEXISTS ("can not check if a user shares any group in the current course with you",
-		   " in the current course with you",
+		   "SELECT EXISTS"
-		   "SELECT COUNT(*)"
+		   "(SELECT *"
 		     " FROM grp_users"
 		    " WHERE UsrCod=%ld"
 		      " AND GrpCod IN"
@@ -418,10 +426,10 @@ unsigned Grp_DB_CheckIfUsrSharesAnyOfMyGrpsInCurrentCrs (long UsrCod)
 			    " WHERE grp_users.UsrCod=%ld"
 			      " AND grp_users.GrpCod=grp_groups.GrpCod"
 			      " AND grp_groups.GrpTypCod=grp_types.GrpTypCod"
-			     " AND grp_types.CrsCod=%ld)",
+			      " AND grp_types.CrsCod=%ld))",
 		   UsrCod,
 		   Gbl.Usrs.Me.UsrDat.UsrCod,
-		   Gbl.Hierarchy.Crs.CrsCod) != 0);
+		   Gbl.Hierarchy.Crs.CrsCod);
   }
 
 /*****************************************************************************/
@@ -678,14 +686,16 @@ long Grp_DB_GetGrpTypeFromGrp (long GrpCod)
 bool Grp_DB_CheckIfAssociatedToGrp (const char *Table,const char *Field,
                                     long Cod,long GrpCod)
   {
-   return (DB_QueryCOUNT ("can not check if associated to a group",
+   return
-			  "SELECT COUNT(*)"
+   DB_QueryEXISTS ("can not check if associated to a group",
+		   "SELECT EXISTS"
+		   "(SELECT *"
 		     " FROM %s"
 		    " WHERE %s=%ld"
-			    " AND GrpCod=%ld",
+		      " AND GrpCod=%ld)",
 		   Table,
 		   Field,Cod,
-		  	  GrpCod) != 0);
+		   GrpCod);
   }
 
 /*****************************************************************************/
@@ -701,12 +711,14 @@ bool Grp_DB_CheckIfAssociatedToGrps (const char *Table,const char *Field,long Co
 
    /***** Check if an assignment, attendance event, survey,
           exam session or match is associated to any group *****/
-   return (DB_QueryCOUNT ("can not check if associated to groups",
+   return
-			  "SELECT COUNT(*)"
+   DB_QueryEXISTS ("can not check if associated to groups",
+		   "SELECT EXISTS"
+		   "(SELECT *"
 		     " FROM %s"
-			  " WHERE %s=%ld",
+		    " WHERE %s=%ld)",
 		   Table,
-			  Field,Cod) != 0);
+		   Field,Cod);
   }
 
 /*****************************************************************************/

swad_group_database.h

@@ -65,7 +65,7 @@ unsigned Grp_DB_GetTchsFromCurrentGrpExceptMe (MYSQL_RES **mysql_res);
 
 bool Grp_DB_CheckIfIBelongToGrpsOfType (long GrpTypCod);
 bool Grp_DB_CheckIfIBelongToGrp (long GrpCod);
-unsigned Grp_DB_CheckIfUsrSharesAnyOfMyGrpsInCurrentCrs (long UsrCod);
+bool Grp_DB_CheckIfUsrSharesAnyOfMyGrpsInCurrentCrs (long UsrCod);
 
 unsigned Grp_DB_GetGrpTypesWithGrpsInCurrentCrs (MYSQL_RES **mysql_res);
 unsigned Grp_DB_GetAllGrpTypesInCurrentCrs (MYSQL_RES **mysql_res);

swad_info_database.c

@@ -277,15 +277,17 @@ void Inf_DB_SetIHaveRead (bool IHaveRead)
 
 bool Inf_DB_CheckIfIHaveReadInfo (void)
   {
-   return (DB_QueryCOUNT ("can not get if I have read course info",
+   return
-			  "SELECT COUNT(*)"
+   DB_QueryEXISTS ("can not check if I have read course info",
+		   "SELECT EXISTS"
+		   "(SELECT *"
 		     " FROM crs_info_read"
 		    " WHERE UsrCod=%ld"
 		      " AND CrsCod=%ld"
-			    " AND InfoType='%s'",
+		      " AND InfoType='%s')",
 		   Gbl.Usrs.Me.UsrDat.UsrCod,
 		   Gbl.Hierarchy.Crs.CrsCod,
-			  Inf_DB_NamesForInfoType[Gbl.Crs.Info.Type]) != 0);
+		   Inf_DB_NamesForInfoType[Gbl.Crs.Info.Type]);
   }
 
 /*****************************************************************************/

swad_institution.c

@@ -1973,7 +1973,7 @@ static void Ins_FormToGoToMap (struct Ins_Instit *Ins)
   {
    extern const char *Txt_Map;
 
-   if (Ctr_DB_GetIfMapIsAvailableInIns (Ins->InsCod))
+   if (Ctr_DB_CheckIfMapIsAvailableInIns (Ins->InsCod))
      {
       Ins_EditingIns = Ins;	// Used to pass parameter with the code of the institution
       Lay_PutContextualLinkOnlyIcon (ActSeeInsInf,NULL,

swad_institution_database.c

@@ -210,14 +210,17 @@ bool Ins_DB_CheckIfInsNameExistsInCty (const char *FieldName,
 				       long InsCod,
 				       long CtyCod)
   {
-   return (DB_QueryCOUNT ("can not check if the name of an institution"
+   return
-			  " already existed",
+   DB_QueryEXISTS ("can not check if the name of an institution already existed",
-			  "SELECT COUNT(*)"
+		   "SELECT EXISTS"
+		   "(SELECT *"
 		     " FROM ins_instits"
 		    " WHERE CtyCod=%ld"
 		      " AND %s='%s'"
-			    " AND InsCod<>%ld",
+		      " AND InsCod<>%ld)",
-			  CtyCod,FieldName,Name,InsCod) != 0);
+		   CtyCod,
+		   FieldName,Name,
+		   InsCod);
   }
 
 /*****************************************************************************/

swad_link_database.c

@@ -131,14 +131,15 @@ unsigned Lnk_DB_GetDataOfLinkByCod (MYSQL_RES **mysql_res,long LnkCod)
 
 bool Lnk_DB_CheckIfLinkNameExists (const char *FieldName,const char *Name,long LnkCod)
   {
-   return (DB_QueryCOUNT ("can not check if the name of an institutional link"
+   return
-			  " already existed",
+   DB_QueryEXISTS ("can not check if the name of an institutional link already existed",
-			  "SELECT COUNT(*)"
+		   "SELECT EXISTS"
+		   "(SELECT *"
 		     " FROM lnk_links"
 		    " WHERE %s='%s'"
-			    " AND LnkCod<>%ld",
+		      " AND LnkCod<>%ld)",
 		   FieldName,Name,
-			  LnkCod) != 0);
+		   LnkCod);
   }
 
 /*****************************************************************************/

swad_mail_database.c

@@ -165,14 +165,16 @@ char Mai_DB_CheckIfEmailIsConfirmed (long UsrCod,const char Email[Cns_MAX_BYTES_
 
 bool Mai_DB_CheckIfEmailBelongToAnotherUsr (long UsrCod,const char Email[Cns_MAX_BYTES_EMAIL_ADDRESS + 1])
   {
-   return (DB_QueryCOUNT ("can not check if email already existed",
+   return
-			  "SELECT COUNT(*)"
+   DB_QueryEXISTS ("can not check if email already existed",
+		   "SELECT EXISTS"
+		   "(SELECT *"
 		     " FROM usr_emails"
 		    " WHERE E_mail='%s'"
 		      " AND Confirmed='Y'"
-			    " AND UsrCod<>%ld",
+		      " AND UsrCod<>%ld)",
 		   Email,
-			  UsrCod) != 0);
+		   UsrCod);
   }
 
 /*****************************************************************************/
@@ -411,15 +413,15 @@ unsigned Mai_DB_GetDataOfMailDomainByCod (MYSQL_RES **mysql_res,long MaiCod)
 
 bool Mai_DB_CheckIfMailDomainNameExists (const char *FieldName,const char *Name,long MaiCod)
   {
-   /***** Get number of mail_domains with a name from database *****/
+   return
-   return (DB_QueryCOUNT ("can not check if the name"
+   DB_QueryEXISTS ("can not check if the name of a mail domain already existed",
-			  " of a mail domain already existed",
+		   "SELECT EXISTS"
-			  "SELECT COUNT(*)"
+		   "(SELECT *"
 		     " FROM ntf_mail_domains"
 		    " WHERE %s='%s'"
-			    " AND MaiCod<>%ld",
+		      " AND MaiCod<>%ld)",
 		   FieldName,Name,
-			  MaiCod) != 0);
+		   MaiCod);
   }
 
 /*****************************************************************************/
@@ -428,13 +430,13 @@ bool Mai_DB_CheckIfMailDomainNameExists (const char *FieldName,const char *Name,
 
 bool Mai_DB_CheckIfMailDomainIsAllowedForNotif (const char MailDomain[Cns_MAX_BYTES_EMAIL_ADDRESS + 1])
   {
-   /***** Get number of mail_domains with a name from database *****/
+   return
-   return (DB_QueryCOUNT ("can not check if a mail domain"
+   DB_QueryEXISTS ("can not check if a mail domain is allowed for notifications",
-			  " is allowed for notifications",
+		   "SELECT EXISTS"
-			  "SELECT COUNT(*)"
+		   "(SELECT *"
 		     " FROM ntf_mail_domains"
-			  " WHERE Domain='%s'",
+		    " WHERE Domain='%s')",
-			  MailDomain) != 0);
+		   MailDomain);
   }
 
 /*****************************************************************************/

swad_match.c

@@ -966,7 +966,7 @@ static void Mch_GetMatchDataFromRow (MYSQL_RES *mysql_res,
    if (Match->Status.Showing == Mch_END)	// Match over
       Match->Status.Playing = false;
    else						// Match not over
-      Match->Status.Playing = Mch_DB_GetIfMatchIsBeingPlayed (Match->MchCod);
+      Match->Status.Playing = Mch_DB_CheckIfMatchIsBeingPlayed (Match->MchCod);
   }
 
 /*****************************************************************************/

swad_match_database.c

@@ -493,8 +493,10 @@ unsigned Mch_DB_GetGrpsAssociatedToMatch (MYSQL_RES **mysql_res,long MchCod)
 
 bool Mch_DB_CheckIfICanPlayThisMatchBasedOnGrps (long MchCod)
   {
-   return (DB_QueryCOUNT ("can not check if I can play a match",
+   return
-			  "SELECT COUNT(*)"
+   DB_QueryEXISTS ("can not check if I can play a match",
+		   "SELECT EXISTS"
+		   "(SELECT *"
 		     " FROM mch_matches"
 		    " WHERE MchCod=%ld"
 		      " AND (MchCod NOT IN"
@@ -506,9 +508,9 @@ bool Mch_DB_CheckIfICanPlayThisMatchBasedOnGrps (long MchCod)
 			      " FROM grp_users,"
 				    "mch_groups"
 			     " WHERE grp_users.UsrCod=%ld"
-				     " AND grp_users.GrpCod=mch_groups.GrpCod))",
+			       " AND grp_users.GrpCod=mch_groups.GrpCod)))",
 		   MchCod,
-			  Gbl.Usrs.Me.UsrDat.UsrCod) != 0);
+		   Gbl.Usrs.Me.UsrDat.UsrCod);
   }
 
 /*****************************************************************************/
@@ -750,16 +752,18 @@ void Mch_DB_RegisterMeAsPlayerInMatch (long MchCod)
   }
 
 /*****************************************************************************/
-/*********************** Get if match is being played ************************/
+/********************** Check if match is being played ***********************/
 /*****************************************************************************/
 
-bool Mch_DB_GetIfMatchIsBeingPlayed (long MchCod)
+bool Mch_DB_CheckIfMatchIsBeingPlayed (long MchCod)
   {
-   return (DB_QueryCOUNT ("can not get if match is being played",
+   return
-			  "SELECT COUNT(*)"
+   DB_QueryEXISTS ("can not check if match is being played",
+		   "SELECT EXISTS"
+		   "(SELECT *"
 		     " FROM mch_playing"
-			  " WHERE MchCod=%ld",
+		    " WHERE MchCod=%ld)",
-			  MchCod) != 0);
+		   MchCod);
   }
 
 /*****************************************************************************/
@@ -923,13 +927,15 @@ void Mch_DB_UpdateMatchPrint (const struct MchPrn_Print *Print)
 
 bool Mch_DB_CheckIfMatchPrintExists (const struct MchPrn_Print *Print)
   {
-   return (DB_QueryCOUNT ("can not get if match print exists",
+   return
-			  "SELECT COUNT(*)"
+   DB_QueryEXISTS ("can not check if match print exists",
+		   "SELECT EXISTS"
+		   "(SELECT *"
 		     " FROM mch_results"
 		    " WHERE MchCod=%ld"
-			    " AND UsrCod=%ld",
+		      " AND UsrCod=%ld)",
 		   Print->MchCod,
-			  Print->UsrCod) != 0);
+		   Print->UsrCod);
   }
 
 /*****************************************************************************/

swad_match_database.h

@@ -95,7 +95,7 @@ void Mch_DB_GetIndexes (long MchCod,unsigned QstInd,
 void Mch_DB_UpdateMatchAsBeingPlayed (long MchCod);
 void Mch_DB_RegisterMeAsPlayerInMatch (long MchCod);
 
-bool Mch_DB_GetIfMatchIsBeingPlayed (long MchCod);
+bool Mch_DB_CheckIfMatchIsBeingPlayed (long MchCod);
 unsigned Mch_DB_GetNumPlayers (long MchCod);
 
 void Mch_DB_RemoveMatchFromBeingPlayed (long MchCod);

swad_message_database.c

@@ -773,11 +773,13 @@ void Msg_DB_GetStatusOfRcvMsg (long MsgCod,
 
 bool Msg_DB_CheckIfSntMsgIsDeleted (long MsgCod)
   {
-   return (DB_QueryCOUNT ("can not check if a sent message is deleted",
+   return
-			  "SELECT COUNT(*)"
+   !DB_QueryEXISTS ("can not check if a sent message is deleted",
+		    "SELECT EXISTS"
+		    "(SELECT *"
 		      " FROM msg_snt"
-			  " WHERE MsgCod=%ld",
+		     " WHERE MsgCod=%ld)",
-			  MsgCod) == 0);	// The message has been deleted
+		    MsgCod);	// The message has been deleted
 				// by its author when it is not present
 				// in table of sent messages undeleted
   }
@@ -788,12 +790,13 @@ bool Msg_DB_CheckIfSntMsgIsDeleted (long MsgCod)
 
 bool Msg_DB_CheckIfRcvMsgIsDeletedForAllItsRecipients (long MsgCod)
   {
-   return (DB_QueryCOUNT ("can not check if a received message"
+   return
-			  " is deleted by all recipients",
+   !DB_QueryEXISTS ("can not check if a received message is deleted by all recipients",
-			  "SELECT COUNT(*)"
+		    "SELECT EXISTS"
+		    "(SELECT *"
 		      " FROM msg_rcv"
-			  " WHERE MsgCod=%ld",
+		     " WHERE MsgCod=%ld)",
-			  MsgCod) == 0);	// The message has been deleted
+		    MsgCod);	// The message has been deleted
 				// by all its recipients when it is not present
 				// in table of received messages undeleted
   }
@@ -1440,13 +1443,15 @@ unsigned Msg_DB_GetUsrsBannedBy (MYSQL_RES **mysql_res,long UsrCod)
 
 bool Msg_DB_CheckIfUsrIsBanned (long FromUsrCod,long ToUsrCod)
   {
-   /***** Get if FromUsrCod is banned by ToUsrCod *****/
+   return
-   return (DB_QueryCOUNT ("can not check if a user is banned",
+   DB_QueryEXISTS ("can not check if a user is banned",
-			  "SELECT COUNT(*)"
+		   "SELECT EXISTS"
+		   "(SELECT *"
 		     " FROM msg_banned"
 		    " WHERE FromUsrCod=%ld"
-			    " AND ToUsrCod=%ld",
+		      " AND ToUsrCod=%ld)",
-			  FromUsrCod,ToUsrCod) != 0);
+		   FromUsrCod,
+		   ToUsrCod);
   }
 
 /*****************************************************************************/

swad_nickname_database.c

@@ -117,13 +117,15 @@ unsigned Nck_DB_GetUsrNicknames (MYSQL_RES **mysql_res,long UsrCod)
 
 bool Nck_DB_CheckIfNickMatchesAnyUsrNick (long UsrCod,const char *NickWithoutArr)
   {
-   return (DB_QueryCOUNT ("can not check if nickname already existed",
+   return
-			  "SELECT COUNT(*)"
+   DB_QueryEXISTS ("can not check if nickname already existed",
+		   "SELECT EXISTS"
+		   "(SELECT *"
 		     " FROM usr_nicknames"
 		    " WHERE UsrCod=%ld"
-			    " AND Nickname='%s'",
+		      " AND Nickname='%s')",
 		   UsrCod,
-			  NickWithoutArr) != 0);
+		   NickWithoutArr);
   }
 
 /*****************************************************************************/
@@ -132,13 +134,15 @@ bool Nck_DB_CheckIfNickMatchesAnyUsrNick (long UsrCod,const char *NickWithoutArr
 
 bool Nck_DB_CheckIfNickMatchesAnyOtherUsrsNicks (long UsrCod,const char *NickWithoutArr)
   {
-   return (DB_QueryCOUNT ("can not check if nickname already existed",
+   return
-			  "SELECT COUNT(*)"
+   DB_QueryEXISTS ("can not check if nickname already existed",
+		   "SELECT EXISTS"
+		   "(SELECT *"
 		     " FROM usr_nicknames"
 		    " WHERE Nickname='%s'"
-			    " AND UsrCod<>%ld",
+		      " AND UsrCod<>%ld)",
 		   NickWithoutArr,
-			  UsrCod) != 0);	// A nickname of another user is the same that user's nickname
+		   UsrCod);	// A nickname of another user is the same that user's nickname
   }
 
 /*****************************************************************************/

swad_place_database.c

@@ -164,16 +164,17 @@ unsigned Plc_DB_GetDataOfPlaceByCod (MYSQL_RES **mysql_res,long PlcCod)
 bool Plc_DB_CheckIfPlaceNameExists (long PlcCod,
                                     const char *FieldName,const char *Name)
   {
-   return (DB_QueryCOUNT ("can not check if the name of a place"
+   return
-			  " already existed",
+   DB_QueryEXISTS ("can not check if the name of a place already existed",
-			  "SELECT COUNT(*)"
+		   "SELECT EXISTS"
+		   "(SELECT *"
 		     " FROM plc_places"
 		    " WHERE InsCod=%ld"
 		      " AND %s='%s'"
-			    " AND PlcCod<>%ld",
+		      " AND PlcCod<>%ld)",
 		   Gbl.Hierarchy.Ins.InsCod,
 		   FieldName,Name,
-			  PlcCod) != 0);
+		   PlcCod);
   }
 
 /*****************************************************************************/

swad_plugin_database.c

@@ -200,15 +200,15 @@ unsigned Plg_DB_GetDataOfPluginByCod (MYSQL_RES **mysql_res,long PlgCod)
 
 bool Plg_DB_CheckIfPluginNameExists (const char *Name,long PlgCod)
   {
-   /***** Get number of plugins with a name from database *****/
+   return
-   return (DB_QueryCOUNT ("can not check if the name of a plugin"
+   DB_QueryEXISTS ("can not check if the name of a plugin already existed",
-			  " already existed",
+		   "SELECT EXISTS"
-			  "SELECT COUNT(*)"
+		   "(SELECT *"
 		     " FROM plg_plugins"
 		    " WHERE Name='%s'"
-			    " AND PlgCod<>%ld",
+		      " AND PlgCod<>%ld)",
 		   Name,
-			  PlgCod) != 0);
+		   PlgCod);
   }
 
 /*****************************************************************************/

swad_room_database.c

@@ -279,17 +279,17 @@ unsigned Roo_DB_GetListRooms (MYSQL_RES **mysql_res,
 bool Roo_DB_CheckIfRoomNameExists (long CtrCod,long RooCod,
                                    const char *FieldName,const char *Name)
   {
-   /***** Get number of rooms with a name from database *****/
+   return
-   return (DB_QueryCOUNT ("can not check if the name of a room"
+   DB_QueryEXISTS ("can not check if the name of a room already existed",
-			  " already existed",
+		   "SELECT EXISTS"
-			  "SELECT COUNT(*)"
+		   "(SELECT *"
 		     " FROM roo_rooms"
 		    " WHERE CtrCod=%ld"
 		      " AND %s='%s'"
-			    " AND RooCod<>%ld",
+		      " AND RooCod<>%ld)",
 		   CtrCod,
 		   FieldName,Name,
-			  RooCod) != 0);
+		   RooCod);
   }
 
 /*****************************************************************************/

swad_session_database.c

@@ -155,12 +155,13 @@ void Ses_DB_UpdateSessionLastRefresh (void)
 
 bool Ses_DB_CheckIfSessionExists (const char *IdSes)
   {
-   /***** Get if session already exists in database *****/
+   return
-   return (DB_QueryCOUNT ("can not check if a session already existed",
+   DB_QueryEXISTS ("can not check if a session already existed",
-			  "SELECT COUNT(*)"
+		   "SELECT EXISTS"
+		   "(SELECT *"
 		     " FROM ses_sessions"
-			  " WHERE SessionId='%s'",
+		    " WHERE SessionId='%s')",
-			  IdSes) != 0);
+		   IdSes);
   }
 
 /*****************************************************************************/
@@ -277,14 +278,15 @@ void Ses_DB_InsertParam (const char *ParamName,const char *ParamValue)
 
 bool Ses_DB_CheckIfParamIsAlreadyStored (const char *ParamName)
   {
-   return (DB_QueryCOUNT ("can not check if a session parameter"
+   return
-			  " is already in database",
+   DB_QueryEXISTS ("can not check if a session parameter is already in database",
-			  "SELECT COUNT(*)"
+		   "SELECT EXISTS"
+		   "(SELECT *"
 		     " FROM ses_params"
 		    " WHERE SessionId='%s'"
-			    " AND ParamName='%s'",
+		      " AND ParamName='%s')",
 		   Gbl.Session.Id,
-			  ParamName) != 0);
+		   ParamName);
   }
 
 /*****************************************************************************/

swad_survey_database.c

@@ -332,18 +332,19 @@ void Svy_DB_GetSurveyTxt (long SvyCod,char Txt[Cns_MAX_BYTES_TEXT + 1])
 
 bool Svy_DB_CheckIfSimilarSurveyExists (const struct Svy_Survey *Svy)
   {
-   /***** Get number of surveys with a field value from database *****/
+   return
-   return (DB_QueryCOUNT ("can not get similar surveys",
+   DB_QueryEXISTS ("can not get similar surveys",
-			  "SELECT COUNT(*)"
+		   "SELECT EXISTS"
+		   "(SELECT *"
 		     " FROM svy_surveys"
 		    " WHERE Scope='%s'"
 		      " AND Cod=%ld"
 		      " AND Title='%s'"
-			    " AND SvyCod<>%ld",
+		      " AND SvyCod<>%ld)",
 		   Sco_GetDBStrFromScope (Svy->Scope),
 		   Svy->Cod,
 		   Svy->Title,
-			  Svy->SvyCod) != 0);
+		   Svy->SvyCod);
   }
 
 /*****************************************************************************/
@@ -749,8 +750,10 @@ unsigned Svy_DB_GetGrpNamesAssociatedToSvy (MYSQL_RES **mysql_res,long SvyCod)
 
 bool Svy_DB_CheckIfICanDoThisSurveyBasedOnGrps (long SvyCod)
   {
-   return (DB_QueryCOUNT ("can not check if I can do a survey",
+   return
-			  "SELECT COUNT(*)"
+   DB_QueryEXISTS ("can not check if I can do a survey",
+		   "SELECT EXISTS"
+		   "(SELECT *"
 		     " FROM svy_surveys"
 		    " WHERE SvyCod=%ld"
 		      " AND (SvyCod NOT IN"
@@ -762,9 +765,9 @@ bool Svy_DB_CheckIfICanDoThisSurveyBasedOnGrps (long SvyCod)
 			      " FROM grp_users,"
 				    "svy_groups"
 			     " WHERE grp_users.UsrCod=%ld"
-				     " AND grp_users.GrpCod=svy_groups.GrpCod))",
+			       " AND grp_users.GrpCod=svy_groups.GrpCod)))",
 		   SvyCod,
-			  Gbl.Usrs.Me.UsrDat.UsrCod) != 0);
+		   Gbl.Usrs.Me.UsrDat.UsrCod);
   }
 
 /*****************************************************************************/
@@ -1087,13 +1090,15 @@ void Svy_DB_IncreaseAnswer (long QstCod,unsigned AnsInd)
 
 bool Svy_DB_CheckIfAnswerExists (long QstCod,unsigned AnsInd)
   {
-   return (DB_QueryCOUNT ("can not check if an answer exists",
+   return
-			  "SELECT COUNT(*)"
+   DB_QueryEXISTS ("can not check if an answer exists",
+		   "SELECT EXISTS"
+		   "(SELECT *"
 		     " FROM svy_answers"
 		    " WHERE QstCod=%ld"
-			    " AND AnsInd=%u",
+		      " AND AnsInd=%u)",
 		   QstCod,
-			  AnsInd) != 0);
+		   AnsInd);
   }
 
 /*****************************************************************************/
@@ -1220,13 +1225,15 @@ void Svy_DB_RegisterIHaveAnsweredSvy (long SvyCod)
 
 bool Svy_DB_CheckIfIHaveAnsweredSvy (long SvyCod)
   {
-   return (DB_QueryCOUNT ("can not check if you have answered a survey",
+   return
-			  "SELECT COUNT(*)"
+   DB_QueryEXISTS ("can not check if you have answered a survey",
+		   "SELECT EXISTS"
+		   "(SELECT *"
 		     " FROM svy_users"
 		    " WHERE SvyCod=%ld"
-			    " AND UsrCod=%ld",
+		      " AND UsrCod=%ld)",
 		   SvyCod,
-			  Gbl.Usrs.Me.UsrDat.UsrCod) != 0);
+		   Gbl.Usrs.Me.UsrDat.UsrCod);
   }
 
 /*****************************************************************************/

swad_tag_database.c

@@ -245,12 +245,13 @@ unsigned Tag_DB_GetEnabledTagsFromThisCrs (MYSQL_RES **mysql_res)
 
 bool Tag_DB_CheckIfCurrentCrsHasTestTags (void)
   {
-   /***** Get available tags from database *****/
+   return
-   return (DB_QueryCOUNT ("can not check if course has tags",
+   DB_QueryEXISTS ("can not check if course has tags",
-			  "SELECT COUNT(*)"
+		   "SELECT EXISTS"
+		   "(SELECT *"
 		     " FROM tst_tags"
-			  " WHERE CrsCod=%ld",
+		    " WHERE CrsCod=%ld)",
-			  Gbl.Hierarchy.Crs.CrsCod) != 0);
+		   Gbl.Hierarchy.Crs.CrsCod);
   }
 
 /*****************************************************************************/

swad_timeline_database.c

@@ -663,7 +663,8 @@ unsigned Tml_DB_GetNumCommsInNote (long NotCod)
 		   " FROM tml_pubs"
 		  " WHERE NotCod=%ld"
 		    " AND PubType=%u",
-		  NotCod,(unsigned) Tml_Pub_COMMENT_TO_NOTE);
+		  NotCod,
+		  (unsigned) Tml_Pub_COMMENT_TO_NOTE);
   }
 
 /*****************************************************************************/
@@ -1186,13 +1187,15 @@ void Tml_DB_RemoveAllPubsPublishedBy (long UsrCod)
 
 bool Tml_DB_CheckIfFavedByUsr (Tml_Usr_FavSha_t FavSha,long Cod,long UsrCod)
   {
-   return (DB_QueryCOUNT ("can not check if a user has favourited",
+   return
-			  "SELECT COUNT(*)"
+   DB_QueryEXISTS ("can not check if a user has favourited",
+		   "SELECT EXISTS"
+		   "(SELECT *"
 		     " FROM %s"
 		    " WHERE %s=%ld"
-			    " AND UsrCod=%ld",
+		      " AND UsrCod=%ld)",
 		   Tml_DB_TableFav[FavSha],
-			  Tml_DB_FieldFav[FavSha],Cod,UsrCod) != 0);
+		   Tml_DB_FieldFav[FavSha],Cod,UsrCod);
   }
 
 /*****************************************************************************/
@@ -1325,15 +1328,17 @@ void Tml_DB_RemoveAllFavsToAllCommsInAllNotesBy (long UsrCod)
 
 bool Tml_DB_CheckIfSharedByUsr (long NotCod,long UsrCod)
   {
-   return (DB_QueryCOUNT ("can not check if a user has shared a note",
+   return
-			  "SELECT COUNT(*)"
+   DB_QueryEXISTS ("can not check if a user has shared a note",
+		   "SELECT EXISTS"
+		   "(SELECT *"
 		     " FROM tml_pubs"
 		    " WHERE NotCod=%ld"
 		      " AND PublisherCod=%ld"
-			    " AND PubType=%u",
+		      " AND PubType=%u)",
 		   NotCod,
 		   UsrCod,
-			  (unsigned) Tml_Pub_SHARED_NOTE) != 0);
+		   (unsigned) Tml_Pub_SHARED_NOTE);
   }
 
 /*****************************************************************************/

swad_user.c

@@ -441,26 +441,9 @@ bool Usr_ItsMe (long UsrCod)
 
 void Usr_GetUsrCodFromEncryptedUsrCod (struct UsrData *UsrDat)
   {
-   MYSQL_RES *mysql_res;
-   MYSQL_ROW row;
-
    if (UsrDat->EnUsrCod[0])
-     {
       /***** Get user's code from database *****/
-      if (DB_QuerySELECT (&mysql_res,"can not get user's code",
+      UsrDat->UsrCod = Usr_DB_GetUsrCodFromEncryptedUsrCod (UsrDat->EnUsrCod);
-			  "SELECT UsrCod"
-			   " FROM usr_data"
-			  " WHERE EncryptedUsrCod='%s'",
-			  UsrDat->EnUsrCod) != 1)
-         Err_ShowErrorAndExit ("Error when getting user's code.");
-
-      /***** Get user's code *****/
-      row = mysql_fetch_row (mysql_res);
-      UsrDat->UsrCod = Str_ConvertStrCodToLongCod (row[0]);
-
-      /***** Free structure that stores the query result *****/
-      DB_FreeMySQLResult (&mysql_res);
-     }
    else
       UsrDat->UsrCod = -1L;
   }
@@ -919,13 +902,14 @@ bool Usr_CheckIfUsrIsSuperuser (long UsrCod)
    /***** 3. Slow check: If not cached, get if a user is superuser from database *****/
    Gbl.Cache.UsrIsSuperuser.UsrCod = UsrCod;
    Gbl.Cache.UsrIsSuperuser.IsSuperuser =
-      (DB_QueryCOUNT ("can not check if a user is superuser",
+   DB_QueryEXISTS ("can not check if a user is superuser",
-		      "SELECT COUNT(*)"
+		   "SELECT EXISTS"
+		   "(SELECT *"
 		     " FROM usr_admins"
 		    " WHERE UsrCod=%ld"
-		        " AND Scope='%s'",
+		      " AND Scope='%s')",
 		   UsrCod,
-		      Sco_GetDBStrFromScope (HieLvl_SYS)) != 0);
+		   Sco_GetDBStrFromScope (HieLvl_SYS));
    return Gbl.Cache.UsrIsSuperuser.IsSuperuser;
   }
 
@@ -2306,10 +2290,11 @@ bool Usr_ChkUsrCodAndGetAllUsrDataFromUsrCod (struct UsrData *UsrDat,
 void Usr_UpdateMyLastData (void)
   {
    /***** Check if it exists an entry for me *****/
-   if (DB_QueryCOUNT ("can not get last user's click",
+   if (DB_QueryEXISTS ("can not check last user's click",
-		      "SELECT COUNT(*)"
+		       "SELECT EXISTS"
+		       "(SELECT *"
 			 " FROM usr_last"
-		      " WHERE UsrCod=%ld",
+		        " WHERE UsrCod=%ld)",
 		       Gbl.Usrs.Me.UsrDat.UsrCod))
       /***** Update my last accessed course, tab and time of click in database *****/
       // WhatToSearch, LastAccNotif remain unchanged

swad_user_database.c

@@ -161,27 +161,29 @@ bool Usr_DB_ChkIfUsrCodExists (long UsrCod)
    if (UsrCod <= 0)	// Wrong user's code
       return false;
 
-   /***** Get if a user exists in database *****/
+   /***** Check if a user exists in database *****/
-   return (DB_QueryCOUNT ("can not check if a user exists",
+   return
-			  "SELECT COUNT(*)"
+   DB_QueryEXISTS ("can not check if a user exists",
+		   "SELECT EXISTS"
+		   "(SELECT *"
 		     " FROM usr_data"
-			  " WHERE UsrCod=%ld",
+		    " WHERE UsrCod=%ld)",
-			  UsrCod) != 0);
+		   UsrCod);
   }
 
 /*****************************************************************************/
-/******** Check if a user exists with a given encrypted user's code **********/
+/******** Get user's code from database using encrypted user's code **********/
 /*****************************************************************************/
+// Input: UsrDat->EncryptedUsrCod must hold user's encrypted code
 
-bool Usr_DB_ChkIfEncryptedUsrCodExists (const char EncryptedUsrCod[Cry_BYTES_ENCRYPTED_STR_SHA256_BASE64])
+long Usr_DB_GetUsrCodFromEncryptedUsrCod (const char EncryptedUsrCod[Cry_BYTES_ENCRYPTED_STR_SHA256_BASE64 + 1])
   {
-   /***** Get if an encrypted user's code already existed in database *****/
+   return
-   return (DB_QueryCOUNT ("can not check if an encrypted user's code"
+   DB_QuerySELECTCode ("can not get user's code",
-			  " already existed",
+		       "SELECT UsrCod"
-			  "SELECT COUNT(*)"
 		        " FROM usr_data"
 		       " WHERE EncryptedUsrCod='%s'",
-			  EncryptedUsrCod) != 0);
+		       EncryptedUsrCod);
   }
 
 /*****************************************************************************/
@@ -190,16 +192,17 @@ bool Usr_DB_ChkIfEncryptedUsrCodExists (const char EncryptedUsrCod[Cry_BYTES_ENC
 
 bool Usr_DB_FindStrInUsrsNames (const char *Str)
   {
-   return (DB_QueryCOUNT ("can not check if a string matches"
+   return
-			  " a first name or a surname",
+   DB_QueryEXISTS ("can not check if a string matches a first name or a surname",
-			  "SELECT COUNT(*)"
+		   "SELECT EXISTS"
+		   "(SELECT *"
 		     " FROM usr_data"
 		    " WHERE FirstName='%s'"
 		       " OR Surname1='%s'"
-			     " OR Surname2='%s'",
+		       " OR Surname2='%s')",
 		   Str,
 		   Str,
-			  Str) != 0);
+		   Str);
   }
 
 /*****************************************************************************/
@@ -363,11 +366,13 @@ void Usr_DB_MarkMyBirthdayAsCongratulated (void)
 
 bool Usr_DB_CheckIfMyBirthdayHasNotBeenCongratulated (void)
   {
-   return (DB_QueryCOUNT ("can not check if my birthday has been congratulated",
+   return
-			  "SELECT COUNT(*)"
+   DB_QueryEXISTS ("can not check if my birthday has been congratulated",
+		   "SELECT EXISTS"
+		   "(SELECT *"
 		     " FROM usr_birthdays_today"
-			  " WHERE UsrCod=%ld",
+		    " WHERE UsrCod=%ld)",
-			  Gbl.Usrs.Me.UsrDat.UsrCod) == 0);
+		   Gbl.Usrs.Me.UsrDat.UsrCod);
   }
 
 /*****************************************************************************/

swad_user_database.h

@@ -66,7 +66,7 @@ void Usr_DB_UpdateMyOfficePhone (void);
 void Usr_DB_UpdateMyLastWhatToSearch (void);
 
 bool Usr_DB_ChkIfUsrCodExists (long UsrCod);
-bool Usr_DB_ChkIfEncryptedUsrCodExists (const char EncryptedUsrCod[Cry_BYTES_ENCRYPTED_STR_SHA256_BASE64]);
+long Usr_DB_GetUsrCodFromEncryptedUsrCod (const char EncryptedUsrCod[Cry_BYTES_ENCRYPTED_STR_SHA256_BASE64 + 1]);
 bool Usr_DB_FindStrInUsrsNames (const char *Str);
 unsigned Usr_DB_GetNumUsrsWhoChoseAnOption (const char *SubQuery);
 unsigned Usr_DB_GetOldUsrs (MYSQL_RES **mysql_res,time_t SecondsWithoutAccess);