diff --git a/swad_changelog.h b/swad_changelog.h
index 76346beb3..46ed75689 100644
--- a/swad_changelog.h
+++ b/swad_changelog.h
@@ -355,10 +355,11 @@ En OpenSWAD:
 ps2pdf source.ps destination.pdf
 */
 
-#define Log_PLATFORM_VERSION	"SWAD 18.12 (2018-11-03)"
+#define Log_PLATFORM_VERSION	"SWAD 18.13 (2018-11-03)"
 #define CSS_FILE		"swad18.4.css"
 #define JS_FILE			"swad17.17.1.js"
 /*
+	Version 18.13:    Nov 03, 2018  Joining building and performing query into one function. (236563 lines)
 	Version 18.12:    Nov 03, 2018  Code refactoring in statistics. (236471 lines)
 	Version 18.11.27: Nov 03, 2018  Joining building and performing query into one function.
 					Some queries that used UNIX_TIMESTAMP(...)>0 optimized using ...>FROM_UNIXTIME(0). (237185 lines)
diff --git a/swad_database.c b/swad_database.c
index 65fbc5bf6..2e06f6fb9 100644
--- a/swad_database.c
+++ b/swad_database.c
@@ -3067,24 +3067,6 @@ void DB_CloseDBConnection (void)
      }
   }
 
-void DB_BuildQuery (const char *fmt,...)
-  {
-   va_list ap;
-   int NumBytesPrinted;
-
-   if (Gbl.DB.QueryPtr != NULL)
-      Lay_ShowErrorAndExit ("Error building query.");
-
-   va_start (ap,fmt);
-   NumBytesPrinted = vasprintf (&Gbl.DB.QueryPtr,fmt,ap);
-   va_end (ap);
-
-   if (NumBytesPrinted < 0)	// If memory allocation wasn't possible,
-				// or some other error occurs,
-				// vasprintf will return -1
-      Lay_NotEnoughMemoryExit ();
-  }
-
 void DB_BuildQuery_old (char **Query,const char *fmt,...)
   {
    va_list ap;
@@ -3172,11 +3154,6 @@ unsigned long DB_QueryCOUNT (const char *MsgError,const char *fmt,...)
    return DB_QueryCOUNT_old (&Query,MsgError);
   }
 
-unsigned long DB_QueryCOUNT_new (const char *MsgError)
-  {
-   return DB_QueryCOUNT_old (&Gbl.DB.QueryPtr,MsgError);
-  }
-
 unsigned long DB_QueryCOUNT_old (char **Query,const char *MsgError)
   {
    MYSQL_RES *mysql_res;
diff --git a/swad_database.h b/swad_database.h
index 59aa80f55..31704c731 100644
--- a/swad_database.h
+++ b/swad_database.h
@@ -37,7 +37,6 @@ void DB_CreateTablesIfNotExist (void);
 void DB_OpenDBConnection (void);
 void DB_CloseDBConnection (void);
 
-void DB_BuildQuery (const char *fmt,...);
 void DB_BuildQuery_old (char **Query,const char *fmt,...);
 
 unsigned long DB_QuerySELECT (MYSQL_RES **mysql_res,const char *MsgError,
@@ -45,7 +44,6 @@ unsigned long DB_QuerySELECT (MYSQL_RES **mysql_res,const char *MsgError,
 unsigned long DB_QuerySELECT_old (char **Query,MYSQL_RES **mysql_res,const char *MsgError);
 
 unsigned long DB_QueryCOUNT (const char *MsgError,const char *fmt,...);
-unsigned long DB_QueryCOUNT_new (const char *MsgError);
 unsigned long DB_QueryCOUNT_old (char **Query,const char *MsgError);
 
 void DB_QueryINSERT (const char *MsgError,const char *fmt,...);
diff --git a/swad_statistic.c b/swad_statistic.c
index 1ecf83ae6..e57c6c2c4 100644
--- a/swad_statistic.c
+++ b/swad_statistic.c
@@ -5436,7 +5436,7 @@ static void Sta_GetAndShowInssOrderedByNumUsrsWhoClaimToBelongToThem (void)
    extern const char *Txt_Institutions_by_number_of_users_who_claim_to_belong_to_them;
    extern const char *Txt_Users;
    MYSQL_RES *mysql_res;
-   unsigned NumInss = 0;
+   unsigned NumInss;
 
    /***** Start box and table *****/
    Box_StartBoxTable ("100%",Txt_Institutions_by_number_of_users_who_claim_to_belong_to_them,
@@ -5447,34 +5447,41 @@ static void Sta_GetAndShowInssOrderedByNumUsrsWhoClaimToBelongToThem (void)
    switch (Gbl.Scope.Current)
      {
       case Sco_SCOPE_SYS:
-	 DB_BuildQuery ("SELECT InsCod,COUNT(*) AS N"
-			" FROM usr_data"
-                        " WHERE InsCod>0"
-			" GROUP BY InsCod"
-			" ORDER BY N DESC");
+	 NumInss =
+	 (unsigned) DB_QuerySELECT (&mysql_res,"can not get institutions",
+				    "SELECT InsCod,COUNT(*) AS N"
+				    " FROM usr_data"
+				    " WHERE InsCod>0"
+				    " GROUP BY InsCod"
+				    " ORDER BY N DESC");
          break;
       case Sco_SCOPE_CTY:
-	 DB_BuildQuery ("SELECT usr_data.InsCod,COUNT(*) AS N"
-			" FROM institutions,usr_data"
-			" WHERE institutions.CtyCod=%ld"
-			" AND institutions.InsCod=usr_data.InsCod"
-			" GROUP BY usr_data.InsCod"
-			" ORDER BY N DESC",
-			Gbl.CurrentCty.Cty.CtyCod);
+	 NumInss =
+	 (unsigned) DB_QuerySELECT (&mysql_res,"can not get institutions",
+				    "SELECT usr_data.InsCod,COUNT(*) AS N"
+				    " FROM institutions,usr_data"
+				    " WHERE institutions.CtyCod=%ld"
+				    " AND institutions.InsCod=usr_data.InsCod"
+				    " GROUP BY usr_data.InsCod"
+				    " ORDER BY N DESC",
+				    Gbl.CurrentCty.Cty.CtyCod);
          break;
       case Sco_SCOPE_INS:
       case Sco_SCOPE_CTR:
       case Sco_SCOPE_DEG:
       case Sco_SCOPE_CRS:
-	 DB_BuildQuery ("SELECT InsCod,COUNT(*) AS N"
-			" FROM usr_data"
-			" WHERE InsCod=%ld"
-			" GROUP BY InsCod"
-			" ORDER BY N DESC",
-			Gbl.CurrentIns.Ins.InsCod);
+	 NumInss =
+	 (unsigned) DB_QuerySELECT (&mysql_res,"can not get institutions",
+				    "SELECT InsCod,COUNT(*) AS N"
+				    " FROM usr_data"
+				    " WHERE InsCod=%ld"
+				    " GROUP BY InsCod"
+				    " ORDER BY N DESC",
+				    Gbl.CurrentIns.Ins.InsCod);
          break;
       default:
 	 Lay_WrongScopeExit ();
+	 NumInss = 0;	// Not reached. Initialized to avoid warning.
 	 break;
      }
 
@@ -9470,7 +9477,7 @@ unsigned Sta_GetNumUsrsWhoChoseAnOption (const char *SubQuery)
       case Sco_SCOPE_SYS:
 	 NumUsrs =
 	 (unsigned) DB_QueryCOUNT ("can not get the number of users"
-				   " who have chosen a privacy",
+				   " who have chosen an option",
 				   "SELECT COUNT(*)"
 				   " FROM usr_data WHERE %s",
 				   SubQuery);
@@ -9478,7 +9485,7 @@ unsigned Sta_GetNumUsrsWhoChoseAnOption (const char *SubQuery)
       case Sco_SCOPE_CTY:
 	 NumUsrs =
 	 (unsigned) DB_QueryCOUNT ("can not get the number of users"
-				   " who have chosen a privacy",
+				   " who have chosen an option",
 				   "SELECT COUNT(DISTINCT usr_data.UsrCod)"
 				   " FROM institutions,centres,degrees,courses,crs_usr,usr_data"
 				   " WHERE institutions.CtyCod=%ld"
@@ -9493,7 +9500,7 @@ unsigned Sta_GetNumUsrsWhoChoseAnOption (const char *SubQuery)
       case Sco_SCOPE_INS:
 	 NumUsrs =
 	 (unsigned) DB_QueryCOUNT ("can not get the number of users"
-				   " who have chosen a privacy",
+				   " who have chosen an option",
 				   "SELECT COUNT(DISTINCT usr_data.UsrCod)"
 				   " FROM centres,degrees,courses,crs_usr,usr_data"
 				   " WHERE centres.InsCod=%ld"
@@ -9507,7 +9514,7 @@ unsigned Sta_GetNumUsrsWhoChoseAnOption (const char *SubQuery)
       case Sco_SCOPE_CTR:
 	 NumUsrs =
 	 (unsigned) DB_QueryCOUNT ("can not get the number of users"
-				   " who have chosen a privacy",
+				   " who have chosen an option",
 				   "SELECT COUNT(DISTINCT usr_data.UsrCod)"
 				   " FROM degrees,courses,crs_usr,usr_data"
 				   " WHERE degrees.CtrCod=%ld"
@@ -9520,7 +9527,7 @@ unsigned Sta_GetNumUsrsWhoChoseAnOption (const char *SubQuery)
       case Sco_SCOPE_DEG:
 	 NumUsrs =
 	 (unsigned) DB_QueryCOUNT ("can not get the number of users"
-				   " who have chosen a privacy",
+				   " who have chosen an option",
 				   "SELECT COUNT(DISTINCT usr_data.UsrCod)"
 				   " FROM courses,crs_usr,usr_data"
 				   " WHERE courses.DegCod=%ld"
@@ -9532,7 +9539,7 @@ unsigned Sta_GetNumUsrsWhoChoseAnOption (const char *SubQuery)
       case Sco_SCOPE_CRS:
 	 NumUsrs =
 	 (unsigned) DB_QueryCOUNT ("can not get the number of users"
-				   " who have chosen a privacy",
+				   " who have chosen an option",
 				   "SELECT COUNT(DISTINCT usr_data.UsrCod)"
 				   " FROM crs_usr,usr_data"
 				   " WHERE crs_usr.CrsCod=%ld"
diff --git a/swad_survey.c b/swad_survey.c
index f3ca314d3..5d61d0271 100644
--- a/swad_survey.c
+++ b/swad_survey.c
@@ -1759,12 +1759,12 @@ static bool Svy_CheckIfSimilarSurveyExists (struct Survey *Svy)
    extern const char *Sco_ScopeDB[Sco_NUM_SCOPES];
 
    /***** Get number of surveys with a field value from database *****/
-   DB_BuildQuery ("SELECT COUNT(*) FROM surveys"
-                  " WHERE Scope='%s' AND Cod=%ld"
-                  " AND Title='%s' AND SvyCod<>%ld",
-		  Sco_ScopeDB[Svy->Scope],Svy->Cod,
-		  Svy->Title,Svy->SvyCod);
-   return (DB_QueryCOUNT_new ("can not get similar surveys") != 0);
+   return (DB_QueryCOUNT ("can not get similar surveys",
+			  "SELECT COUNT(*) FROM surveys"
+			  " WHERE Scope='%s' AND Cod=%ld"
+			  " AND Title='%s' AND SvyCod<>%ld",
+			  Sco_ScopeDB[Svy->Scope],Svy->Cod,
+			  Svy->Title,Svy->SvyCod) != 0);
   }
 
 /*****************************************************************************/
@@ -2326,8 +2326,9 @@ static void Svy_UpdateSurvey (struct Survey *Svy,const char *Txt)
 static bool Svy_CheckIfSvyIsAssociatedToGrps (long SvyCod)
   {
    /***** Get if a survey is associated to a group from database *****/
-   DB_BuildQuery ("SELECT COUNT(*) FROM svy_grp WHERE SvyCod=%ld",SvyCod);
-   return (DB_QueryCOUNT_new ("can not check if a survey is associated to groups") != 0);
+   return (DB_QueryCOUNT ("can not check if a survey is associated to groups",
+			  "SELECT COUNT(*) FROM svy_grp WHERE SvyCod=%ld",
+			  SvyCod) != 0);
   }
 
 /*****************************************************************************/
@@ -2337,10 +2338,10 @@ static bool Svy_CheckIfSvyIsAssociatedToGrps (long SvyCod)
 bool Svy_CheckIfSvyIsAssociatedToGrp (long SvyCod,long GrpCod)
   {
    /***** Get if a survey is associated to a group from database *****/
-   DB_BuildQuery ("SELECT COUNT(*) FROM svy_grp"
-	          " WHERE SvyCod=%ld AND GrpCod=%ld",
-		  SvyCod,GrpCod);
-   return (DB_QueryCOUNT_new ("can not check if a survey is associated to a group") != 0);
+   return (DB_QueryCOUNT ("can not check if a survey is associated to a group",
+			  "SELECT COUNT(*) FROM svy_grp"
+			  " WHERE SvyCod=%ld AND GrpCod=%ld",
+			  SvyCod,GrpCod) != 0);
   }
 
 /*****************************************************************************/
@@ -2532,14 +2533,14 @@ void Svy_RemoveSurveys (Sco_Scope_t Scope,long Cod)
 static bool Svy_CheckIfICanDoThisSurveyBasedOnGrps (long SvyCod)
   {
    /***** Get if I can do a survey from database *****/
-   DB_BuildQuery ("SELECT COUNT(*) FROM surveys"
-                  " WHERE SvyCod=%ld"
-                  " AND (SvyCod NOT IN (SELECT SvyCod FROM svy_grp) OR"
-                  " SvyCod IN (SELECT svy_grp.SvyCod FROM svy_grp,crs_grp_usr"
-                  " WHERE crs_grp_usr.UsrCod=%ld"
-                  " AND svy_grp.GrpCod=crs_grp_usr.GrpCod))",
-		  SvyCod,Gbl.Usrs.Me.UsrDat.UsrCod);
-   return (DB_QueryCOUNT_new ("can not check if I can do a survey") != 0);
+   return (DB_QueryCOUNT ("can not check if I can do a survey",
+			  "SELECT COUNT(*) FROM surveys"
+			  " WHERE SvyCod=%ld"
+			  " AND (SvyCod NOT IN (SELECT SvyCod FROM svy_grp) OR"
+			  " SvyCod IN (SELECT svy_grp.SvyCod FROM svy_grp,crs_grp_usr"
+			  " WHERE crs_grp_usr.UsrCod=%ld"
+			  " AND svy_grp.GrpCod=crs_grp_usr.GrpCod))",
+			  SvyCod,Gbl.Usrs.Me.UsrDat.UsrCod) != 0);
   }
 
 /*****************************************************************************/
@@ -2549,8 +2550,11 @@ static bool Svy_CheckIfICanDoThisSurveyBasedOnGrps (long SvyCod)
 static unsigned Svy_GetNumQstsSvy (long SvyCod)
   {
    /***** Get data of questions from database *****/
-   DB_BuildQuery ("SELECT COUNT(*) FROM svy_questions WHERE SvyCod=%ld",SvyCod);
-   return (unsigned) DB_QueryCOUNT_new ("can not get number of questions of a survey");
+   return
+   (unsigned) DB_QueryCOUNT ("can not get number of questions of a survey",
+			     "SELECT COUNT(*) FROM svy_questions"
+			     " WHERE SvyCod=%ld",
+			     SvyCod);
   }
 
 /*****************************************************************************/
@@ -2849,10 +2853,10 @@ static Svy_AnswerType_t Svy_ConvertFromStrAnsTypDBToAnsTyp (const char *StrAnsTy
 static bool Svy_CheckIfAnswerExists (long QstCod,unsigned AnsInd)
   {
    /***** Get answers of a question from database *****/
-   DB_BuildQuery ("SELECT COUNT(*) FROM svy_answers"
-                  " WHERE QstCod=%ld AND AnsInd=%u",
-		  QstCod,AnsInd);
-   return (DB_QueryCOUNT_new ("can not check if an answer exists") != 0);
+   return (DB_QueryCOUNT ("can not check if an answer exists",
+			  "SELECT COUNT(*) FROM svy_answers"
+			  " WHERE QstCod=%ld AND AnsInd=%u",
+			  QstCod,AnsInd) != 0);
   }
 
 /*****************************************************************************/
@@ -3748,10 +3752,10 @@ static void Svy_RegisterIHaveAnsweredSvy (long SvyCod)
 static bool Svy_CheckIfIHaveAnsweredSvy (long SvyCod)
   {
    /***** Get number of surveys with a field value from database *****/
-   DB_BuildQuery ("SELECT COUNT(*) FROM svy_users"
-                  " WHERE SvyCod=%ld AND UsrCod=%ld",
-		  SvyCod,Gbl.Usrs.Me.UsrDat.UsrCod);
-   return (DB_QueryCOUNT_new ("can not check if you have answered a survey") != 0);
+   return (DB_QueryCOUNT ("can not check if you have answered a survey",
+			  "SELECT COUNT(*) FROM svy_users"
+			  " WHERE SvyCod=%ld AND UsrCod=%ld",
+			  SvyCod,Gbl.Usrs.Me.UsrDat.UsrCod) != 0);
   }
 
 /*****************************************************************************/
@@ -3761,8 +3765,12 @@ static bool Svy_CheckIfIHaveAnsweredSvy (long SvyCod)
 static unsigned Svy_GetNumUsrsWhoHaveAnsweredSvy (long SvyCod)
   {
    /***** Get number of surveys with a field value from database *****/
-   DB_BuildQuery ("SELECT COUNT(*) FROM svy_users WHERE SvyCod=%ld",SvyCod);
-   return (unsigned) DB_QueryCOUNT_new ("can not get number of users who have answered a survey");
+   return
+   (unsigned) DB_QueryCOUNT ("can not get number of users"
+			     " who have answered a survey",
+			     "SELECT COUNT(*) FROM svy_users"
+			     " WHERE SvyCod=%ld",
+			     SvyCod);
   }
 
 /*****************************************************************************/
diff --git a/swad_user.c b/swad_user.c
index ae852d2ba..705846a44 100644
--- a/swad_user.c
+++ b/swad_user.c
@@ -838,10 +838,10 @@ bool Usr_CheckIfUsrIsAdm (long UsrCod,Sco_Scope_t Scope,long Cod)
    if (Sco_ScopeDB[Scope])
      {
       /***** Get if a user is administrator of a degree from database *****/
-      DB_BuildQuery ("SELECT COUNT(*) FROM admin"
-		     " WHERE UsrCod=%ld AND Scope='%s' AND Cod=%ld",
-		     UsrCod,Sco_ScopeDB[Scope],Cod);
-      return (DB_QueryCOUNT_new ("can not check if a user is administrator") != 0);
+      return (DB_QueryCOUNT ("can not check if a user is administrator",
+			     "SELECT COUNT(*) FROM admin"
+			     " WHERE UsrCod=%ld AND Scope='%s' AND Cod=%ld",
+			     UsrCod,Sco_ScopeDB[Scope],Cod) != 0);
      }
    return false;
   }
@@ -869,11 +869,12 @@ bool Usr_CheckIfUsrIsSuperuser (long UsrCod)
       return Gbl.Cache.UsrIsSuperuser.IsSuperuser;
 
    /***** 3. Slow check: If not cached, get if a user is superuser from database *****/
-   DB_BuildQuery ("SELECT COUNT(*) FROM admin"
-		  " WHERE UsrCod=%ld AND Scope='%s'",
-		  UsrCod,Sco_ScopeDB[Sco_SCOPE_SYS]);
    Gbl.Cache.UsrIsSuperuser.UsrCod = UsrCod;
-   Gbl.Cache.UsrIsSuperuser.IsSuperuser = (DB_QueryCOUNT_new ("can not check if a user is superuser") != 0);
+   Gbl.Cache.UsrIsSuperuser.IsSuperuser =
+      (DB_QueryCOUNT ("can not check if a user is superuser",
+		      "SELECT COUNT(*) FROM admin"
+		      " WHERE UsrCod=%ld AND Scope='%s'",
+		      UsrCod,Sco_ScopeDB[Sco_SCOPE_SYS]) != 0);
    return Gbl.Cache.UsrIsSuperuser.IsSuperuser;
   }
 
@@ -962,8 +963,10 @@ bool Usr_ICanEditOtherUsr (const struct UsrData *UsrDat)
 unsigned Usr_GetNumCrssOfUsr (long UsrCod)
   {
    /***** Get the number of courses of a user from database ******/
-   DB_BuildQuery ("SELECT COUNT(*) FROM crs_usr WHERE UsrCod=%ld",UsrCod);
-   return (unsigned) DB_QueryCOUNT_new ("can not get the number of courses of a user");
+   return
+   (unsigned) DB_QueryCOUNT ("can not get the number of courses of a user",
+			     "SELECT COUNT(*) FROM crs_usr WHERE UsrCod=%ld",
+			     UsrCod);
   }
 
 /*****************************************************************************/
@@ -973,10 +976,11 @@ unsigned Usr_GetNumCrssOfUsr (long UsrCod)
 unsigned Usr_GetNumCrssOfUsrNotAccepted (long UsrCod)
   {
    /***** Get the number of courses of a user not accepted from database ******/
-   DB_BuildQuery ("SELECT COUNT(*) FROM crs_usr"
-	          " WHERE UsrCod=%ld AND Accepted='N'",
-		  UsrCod);
-   return (unsigned) DB_QueryCOUNT_new ("can not get the number of courses of a user");
+   return
+   (unsigned) DB_QueryCOUNT ("can not get the number of courses of a user",
+			     "SELECT COUNT(*) FROM crs_usr"
+			     " WHERE UsrCod=%ld AND Accepted='N'",
+			     UsrCod);
   }
 
 /*****************************************************************************/
@@ -986,10 +990,12 @@ unsigned Usr_GetNumCrssOfUsrNotAccepted (long UsrCod)
 unsigned Usr_GetNumCrssOfUsrWithARole (long UsrCod,Rol_Role_t Role)
   {
    /***** Get the number of courses of a user with a role from database ******/
-   DB_BuildQuery ("SELECT COUNT(*) FROM crs_usr"
-                  " WHERE UsrCod=%ld AND Role=%u",
-		  UsrCod,(unsigned) Role);
-   return (unsigned) DB_QueryCOUNT_new ("can not get the number of courses of a user with a role");
+   return
+   (unsigned) DB_QueryCOUNT ("can not get the number of courses of a user"
+			     " with a role",
+			     "SELECT COUNT(*) FROM crs_usr"
+			     " WHERE UsrCod=%ld AND Role=%u",
+			     UsrCod,(unsigned) Role);
   }
 
 /*****************************************************************************/
@@ -999,10 +1005,12 @@ unsigned Usr_GetNumCrssOfUsrWithARole (long UsrCod,Rol_Role_t Role)
 unsigned Usr_GetNumCrssOfUsrWithARoleNotAccepted (long UsrCod,Rol_Role_t Role)
   {
    /***** Get the number of courses of a user with a role from database ******/
-   DB_BuildQuery ("SELECT COUNT(*) FROM crs_usr"
-                  " WHERE UsrCod=%ld AND Role=%u AND Accepted='N'",
-		  UsrCod,(unsigned) Role);
-   return (unsigned) DB_QueryCOUNT_new ("can not get the number of courses of a user with a role");
+   return
+   (unsigned) DB_QueryCOUNT ("can not get the number of courses of a user"
+			     " with a role",
+			     "SELECT COUNT(*) FROM crs_usr"
+			     " WHERE UsrCod=%ld AND Role=%u AND Accepted='N'",
+			     UsrCod,(unsigned) Role);
   }
 
 /*****************************************************************************/
@@ -1064,12 +1072,13 @@ unsigned Usr_GetNumUsrsInCrssOfAUsr (long UsrCod,Rol_Role_t UsrRole,
 	 Lay_ShowErrorAndExit ("Wrong role.");
 	 break;
      }
-   DB_BuildQuery ("SELECT COUNT(DISTINCT crs_usr.UsrCod)"
-	          " FROM crs_usr,usr_courses_tmp"
-                  " WHERE crs_usr.CrsCod=usr_courses_tmp.CrsCod"
-                  "%s",
-		  SubQueryRole);
-   NumUsrs = (unsigned) DB_QueryCOUNT_new ("can not get the number of users");
+   NumUsrs =
+   (unsigned) DB_QueryCOUNT ("can not get the number of users",
+			     "SELECT COUNT(DISTINCT crs_usr.UsrCod)"
+			     " FROM crs_usr,usr_courses_tmp"
+			     " WHERE crs_usr.CrsCod=usr_courses_tmp.CrsCod"
+			     "%s",
+			     SubQueryRole);
 
    /***** Remove temporary table *****/
    DB_Query ("can not remove temporary tables",
@@ -1405,12 +1414,13 @@ bool Usr_CheckIfUsrSharesAnyOfMyCrs (struct UsrData *UsrDat)
    Usr_GetMyCourses ();
 
    /* Check if user shares any course with me */
-   DB_BuildQuery ("SELECT COUNT(*) FROM crs_usr"
-	          " WHERE UsrCod=%ld"
-	          " AND CrsCod IN (SELECT CrsCod FROM my_courses_tmp)",
-		  UsrDat->UsrCod);
-   Gbl.Cache.UsrSharesAnyOfMyCrs.SharesAnyOfMyCrs = DB_QueryCOUNT_new ("can not check if a user shares any course with you") != 0;
    Gbl.Cache.UsrSharesAnyOfMyCrs.UsrCod = UsrDat->UsrCod;
+   Gbl.Cache.UsrSharesAnyOfMyCrs.SharesAnyOfMyCrs =
+      (DB_QueryCOUNT ("can not check if a user shares any course with you",
+		      "SELECT COUNT(*) FROM crs_usr"
+		      " WHERE UsrCod=%ld"
+		      " AND CrsCod IN (SELECT CrsCod FROM my_courses_tmp)",
+		      UsrDat->UsrCod) != 0);
    return Gbl.Cache.UsrSharesAnyOfMyCrs.SharesAnyOfMyCrs;
   }
 
@@ -1444,10 +1454,11 @@ bool Usr_CheckIfUsrSharesAnyOfMyCrsWithDifferentRole (long UsrCod)
 	     UsrCod);
 
    /* Get if a user shares any course with me from database */
-   DB_BuildQuery ("SELECT COUNT(*) 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");
-   UsrSharesAnyOfMyCrsWithDifferentRole = (DB_QueryCOUNT_new ("can not check if a user shares any course with you") != 0);
+   UsrSharesAnyOfMyCrsWithDifferentRole =
+      (DB_QueryCOUNT ("can not check if a user shares any course with you",
+		      "SELECT COUNT(*) 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);
 
    /* Remove temporary table if exists */
    DB_Query ("can not remove temporary tables",
@@ -1827,18 +1838,19 @@ bool Usr_CheckIfUsrBelongsToIns (long UsrCod,long InsCod)
       return Gbl.Cache.UsrBelongsToIns.Belongs;
 
    /***** 3. Slow check: Get is user belongs to institution from database *****/
-   DB_BuildQuery ("SELECT COUNT(DISTINCT centres.InsCod)"
-		  " FROM crs_usr,courses,degrees,centres"
-		  " WHERE crs_usr.UsrCod=%ld"
-		  " AND crs_usr.Accepted='Y'"
-		  " AND crs_usr.CrsCod=courses.CrsCod"
-		  " AND courses.DegCod=degrees.DegCod"
-		  " AND degrees.CtrCod=centres.CtrCod"
-		  " AND centres.InsCod=%ld",
-		  UsrCod,InsCod);
    Gbl.Cache.UsrBelongsToIns.UsrCod = UsrCod;
    Gbl.Cache.UsrBelongsToIns.InsCod = InsCod;
-   Gbl.Cache.UsrBelongsToIns.Belongs = (DB_QueryCOUNT_new ("can not check if a user belongs to an institution") != 0);
+   Gbl.Cache.UsrBelongsToIns.Belongs =
+      (DB_QueryCOUNT ("can not check if a user belongs to an institution",
+		      "SELECT COUNT(DISTINCT centres.InsCod)"
+		      " FROM crs_usr,courses,degrees,centres"
+		      " WHERE crs_usr.UsrCod=%ld"
+		      " AND crs_usr.Accepted='Y'"
+		      " AND crs_usr.CrsCod=courses.CrsCod"
+		      " AND courses.DegCod=degrees.DegCod"
+		      " AND degrees.CtrCod=centres.CtrCod"
+		      " AND centres.InsCod=%ld",
+		      UsrCod,InsCod) != 0);
    return Gbl.Cache.UsrBelongsToIns.Belongs;
   }
 
@@ -1866,17 +1878,18 @@ bool Usr_CheckIfUsrBelongsToCtr (long UsrCod,long CtrCod)
       return Gbl.Cache.UsrBelongsToCtr.Belongs;
 
    /***** 3. Slow check: Get is user belongs to centre from database *****/
-   DB_BuildQuery ("SELECT COUNT(DISTINCT degrees.CtrCod)"
-		  " FROM crs_usr,courses,degrees"
-		  " WHERE crs_usr.UsrCod=%ld"
-		  " AND crs_usr.Accepted='Y'"	// Only if user accepted
-		  " AND crs_usr.CrsCod=courses.CrsCod"
-		  " AND courses.DegCod=degrees.DegCod"
-		  " AND degrees.CtrCod=%ld",
-		  UsrCod,CtrCod);
    Gbl.Cache.UsrBelongsToCtr.UsrCod = UsrCod;
    Gbl.Cache.UsrBelongsToCtr.CtrCod = CtrCod;
-   Gbl.Cache.UsrBelongsToCtr.Belongs = (DB_QueryCOUNT_new ("can not check if a user belongs to a centre") != 0);
+   Gbl.Cache.UsrBelongsToCtr.Belongs =
+      (DB_QueryCOUNT ("can not check if a user belongs to a centre",
+		      "SELECT COUNT(DISTINCT degrees.CtrCod)"
+		      " FROM crs_usr,courses,degrees"
+		      " WHERE crs_usr.UsrCod=%ld"
+		      " AND crs_usr.Accepted='Y'"	// Only if user accepted
+		      " AND crs_usr.CrsCod=courses.CrsCod"
+		      " AND courses.DegCod=degrees.DegCod"
+		      " AND degrees.CtrCod=%ld",
+		      UsrCod,CtrCod) != 0);
    return Gbl.Cache.UsrBelongsToCtr.Belongs;
   }
 
@@ -1904,16 +1917,17 @@ bool Usr_CheckIfUsrBelongsToDeg (long UsrCod,long DegCod)
       return Gbl.Cache.UsrBelongsToDeg.Belongs;
 
    /***** 3. Slow check: Get if user belongs to degree from database *****/
-   DB_BuildQuery ("SELECT COUNT(DISTINCT courses.DegCod)"
-		  " FROM crs_usr,courses"
-		  " WHERE crs_usr.UsrCod=%ld"
-		  " AND crs_usr.Accepted='Y'"	// Only if user accepted
-		  " AND crs_usr.CrsCod=courses.CrsCod"
-		  " AND courses.DegCod=%ld",
-		  UsrCod,DegCod);
    Gbl.Cache.UsrBelongsToDeg.UsrCod = UsrCod;
    Gbl.Cache.UsrBelongsToDeg.DegCod = DegCod;
-   Gbl.Cache.UsrBelongsToDeg.Belongs = (DB_QueryCOUNT_new ("can not check if a user belongs to a degree") != 0);
+   Gbl.Cache.UsrBelongsToDeg.Belongs =
+      (DB_QueryCOUNT ("can not check if a user belongs to a degree",
+		      "SELECT COUNT(DISTINCT courses.DegCod)"
+		      " FROM crs_usr,courses"
+		      " WHERE crs_usr.UsrCod=%ld"
+		      " AND crs_usr.Accepted='Y'"	// Only if user accepted
+		      " AND crs_usr.CrsCod=courses.CrsCod"
+		      " AND courses.DegCod=%ld",
+		      UsrCod,DegCod) != 0);
    return Gbl.Cache.UsrBelongsToDeg.Belongs;
   }
 
@@ -1948,13 +1962,14 @@ bool Usr_CheckIfUsrBelongsToCrs (long UsrCod,long CrsCod,
    /***** 3. Slow check: Get if user belongs to course from database *****/
    SubQuery = (CountOnlyAcceptedCourses ? " AND crs_usr.Accepted='Y'" :
 	                                  "");
-   DB_BuildQuery ("SELECT COUNT(*) FROM crs_usr"
-	          " WHERE CrsCod=%ld AND UsrCod=%ld%s",
-		  CrsCod,UsrCod,SubQuery);
    Gbl.Cache.UsrBelongsToCrs.UsrCod = UsrCod;
    Gbl.Cache.UsrBelongsToCrs.CrsCod = CrsCod;
    Gbl.Cache.UsrBelongsToCrs.CountOnlyAcceptedCourses = CountOnlyAcceptedCourses;
-   Gbl.Cache.UsrBelongsToCrs.Belongs = (DB_QueryCOUNT_new ("can not check if a user belongs to a course") != 0);
+   Gbl.Cache.UsrBelongsToCrs.Belongs =
+      (DB_QueryCOUNT ("can not check if a user belongs to a course",
+		      "SELECT COUNT(*) FROM crs_usr"
+		      " WHERE CrsCod=%ld AND UsrCod=%ld%s",
+		      CrsCod,UsrCod,SubQuery) != 0);
    return Gbl.Cache.UsrBelongsToCrs.Belongs;
   }
 
@@ -2334,9 +2349,11 @@ unsigned long Usr_GetCrssFromUsr (long UsrCod,long DegCod,MYSQL_RES **mysql_res)
 bool Usr_ChkIfEncryptedUsrCodExists (const char EncryptedUsrCod[Cry_BYTES_ENCRYPTED_STR_SHA256_BASE64])
   {
    /***** Get if an encrypted user's code already existed in database *****/
-   DB_BuildQuery ("SELECT COUNT(*) FROM usr_data WHERE EncryptedUsrCod='%s'",
-		  EncryptedUsrCod);
-   return (DB_QueryCOUNT_new ("can not check if an encrypted user's code already existed") != 0);
+   return (DB_QueryCOUNT ("can not check if an encrypted user's code"
+			  " already existed",
+			  "SELECT COUNT(*) FROM usr_data"
+			  " WHERE EncryptedUsrCod='%s'",
+			  EncryptedUsrCod) != 0);
   }
 
 /*****************************************************************************/
@@ -2569,9 +2586,10 @@ void Usr_CreateBirthdayStrDB (const struct UsrData *UsrDat,
 static bool Usr_CheckIfMyBirthdayHasNotBeenCongratulated (void)
   {
    /***** Delete old birthdays *****/
-   DB_BuildQuery ("SELECT COUNT(*) FROM birthdays_today WHERE UsrCod=%ld",
-		  Gbl.Usrs.Me.UsrDat.UsrCod);
-   return (DB_QueryCOUNT_new ("can not check if my birthday has been congratulated") == 0);
+   return (DB_QueryCOUNT ("can not check if my birthday has been congratulated",
+			  "SELECT COUNT(*) FROM birthdays_today"
+			  " WHERE UsrCod=%ld",
+			  Gbl.Usrs.Me.UsrDat.UsrCod) == 0);
   }
 
 /*****************************************************************************/
@@ -3389,9 +3407,9 @@ bool Usr_ChkUsrCodAndGetAllUsrDataFromUsrCod (struct UsrData *UsrDat)
 void Usr_UpdateMyLastData (void)
   {
    /***** Check if it exists an entry for me *****/
-   DB_BuildQuery ("SELECT COUNT(*) FROM usr_last WHERE UsrCod=%ld",
-		  Gbl.Usrs.Me.UsrDat.UsrCod);
-   if (DB_QueryCOUNT_new ("can not get last user's click"))
+   if (DB_QueryCOUNT ("can not get last user's click",
+		      "SELECT COUNT(*) FROM usr_last WHERE UsrCod=%ld",
+		      Gbl.Usrs.Me.UsrDat.UsrCod))
       /***** Update my last accessed course, tab and time of click in database *****/
       // WhatToSearch, LastAccNotif remain unchanged
       DB_QueryUPDATE ("can not update last user's data",
@@ -3966,10 +3984,11 @@ static void Usr_WriteUsrData (const char *BgColor,
 unsigned Usr_GetNumUsrsInCrs (Rol_Role_t Role,long CrsCod)
   {
    /***** Get the number of teachers in a course from database ******/
-   DB_BuildQuery ("SELECT COUNT(*) FROM crs_usr"
-	          " WHERE CrsCod=%ld AND Role=%u",
-		  CrsCod,(unsigned) Role);
-   return (unsigned) DB_QueryCOUNT_new ("can not get the number of users in a course");
+   return
+   (unsigned) DB_QueryCOUNT ("can not get the number of users in a course",
+			     "SELECT COUNT(*) FROM crs_usr"
+			     " WHERE CrsCod=%ld AND Role=%u",
+			     CrsCod,(unsigned) Role);
   }
 
 /*****************************************************************************/
@@ -3979,13 +3998,15 @@ unsigned Usr_GetNumUsrsInCrs (Rol_Role_t Role,long CrsCod)
 unsigned Usr_GetNumUsrsInCrssOfDeg (Rol_Role_t Role,long DegCod)
   {
    /***** Get the number of users in courses of a degree from database ******/
-   DB_BuildQuery ("SELECT COUNT(DISTINCT crs_usr.UsrCod)"
-	          " FROM courses,crs_usr"
-                  " WHERE courses.DegCod=%ld"
-                  " AND courses.CrsCod=crs_usr.CrsCod"
-                  " AND crs_usr.Role=%u",
-		  DegCod,(unsigned) Role);
-   return (unsigned) DB_QueryCOUNT_new ("can not get the number of users in courses of a degree");
+   return
+   (unsigned) DB_QueryCOUNT ("can not get the number of users"
+			     " in courses of a degree",
+			     "SELECT COUNT(DISTINCT crs_usr.UsrCod)"
+			     " FROM courses,crs_usr"
+			     " WHERE courses.DegCod=%ld"
+			     " AND courses.CrsCod=crs_usr.CrsCod"
+			     " AND crs_usr.Role=%u",
+			     DegCod,(unsigned) Role);
   }
 
 /*****************************************************************************/
@@ -3995,25 +4016,33 @@ unsigned Usr_GetNumUsrsInCrssOfDeg (Rol_Role_t Role,long DegCod)
 
 unsigned Usr_GetNumUsrsInCrssOfCtr (Rol_Role_t Role,long CtrCod)
   {
+   unsigned NumUsrs;
+
    /***** Get the number of users in courses of a centre from database ******/
    if (Role == Rol_UNK)	// Any user
-      DB_BuildQuery ("SELECT COUNT(DISTINCT crs_usr.UsrCod)"
-		     " FROM degrees,courses,crs_usr"
-		     " WHERE degrees.CtrCod=%ld"
-		     " AND degrees.DegCod=courses.DegCod"
-		     " AND courses.CrsCod=crs_usr.CrsCod",
-		     CtrCod);
+      NumUsrs =
+      (unsigned) DB_QueryCOUNT ("can not get the number of users"
+				" in courses of a centre",
+				"SELECT COUNT(DISTINCT crs_usr.UsrCod)"
+				" FROM degrees,courses,crs_usr"
+				" WHERE degrees.CtrCod=%ld"
+				" AND degrees.DegCod=courses.DegCod"
+				" AND courses.CrsCod=crs_usr.CrsCod",
+				CtrCod);
    else
       // This query is very slow.
       // It's a bad idea to get number of teachers or students for a big list of centres
-      DB_BuildQuery ("SELECT COUNT(DISTINCT crs_usr.UsrCod)"
-		     " FROM degrees,courses,crs_usr"
-		     " WHERE degrees.CtrCod=%ld"
-		     " AND degrees.DegCod=courses.DegCod"
-		     " AND courses.CrsCod=crs_usr.CrsCod"
-		     " AND crs_usr.Role=%u",
-		     CtrCod,(unsigned) Role);
-   return (unsigned) DB_QueryCOUNT_new ("can not get the number of users in courses of a centre");
+      NumUsrs =
+      (unsigned) DB_QueryCOUNT ("can not get the number of users"
+				" in courses of a centre",
+				"SELECT COUNT(DISTINCT crs_usr.UsrCod)"
+				" FROM degrees,courses,crs_usr"
+				" WHERE degrees.CtrCod=%ld"
+				" AND degrees.DegCod=courses.DegCod"
+				" AND courses.CrsCod=crs_usr.CrsCod"
+				" AND crs_usr.Role=%u",
+				CtrCod,(unsigned) Role);
+   return NumUsrs;
   }
 
 /*****************************************************************************/
@@ -4023,27 +4052,35 @@ unsigned Usr_GetNumUsrsInCrssOfCtr (Rol_Role_t Role,long CtrCod)
 
 unsigned Usr_GetNumUsrsInCrssOfIns (Rol_Role_t Role,long InsCod)
   {
+   unsigned NumUsrs;
+
    /***** Get the number of users in courses of an institution from database ******/
    if (Role == Rol_UNK)	// Any user
-      DB_BuildQuery ("SELECT COUNT(DISTINCT crs_usr.UsrCod)"
-		     " FROM centres,degrees,courses,crs_usr"
-		     " WHERE centres.InsCod=%ld"
-		     " AND centres.CtrCod=degrees.CtrCod"
-		     " AND degrees.DegCod=courses.DegCod"
-		     " AND courses.CrsCod=crs_usr.CrsCod",
-		     InsCod);
+      NumUsrs =
+      (unsigned) DB_QueryCOUNT ("can not get the number of users"
+				" in courses of an institution",
+				"SELECT COUNT(DISTINCT crs_usr.UsrCod)"
+				" FROM centres,degrees,courses,crs_usr"
+				" WHERE centres.InsCod=%ld"
+				" AND centres.CtrCod=degrees.CtrCod"
+				" AND degrees.DegCod=courses.DegCod"
+				" AND courses.CrsCod=crs_usr.CrsCod",
+				InsCod);
    else
       // This query is very slow.
       // It's a bad idea to get number of teachers or students for a big list of institutions
-      DB_BuildQuery ("SELECT COUNT(DISTINCT crs_usr.UsrCod)"
-		     " FROM centres,degrees,courses,crs_usr"
-		     " WHERE centres.InsCod=%ld"
-		     " AND centres.CtrCod=degrees.CtrCod"
-		     " AND degrees.DegCod=courses.DegCod"
-		     " AND courses.CrsCod=crs_usr.CrsCod"
-		     " AND crs_usr.Role=%u",
-		     InsCod,(unsigned) Role);
-   return (unsigned) DB_QueryCOUNT_new ("can not get the number of users in courses of an institution");
+      NumUsrs =
+      (unsigned) DB_QueryCOUNT ("can not get the number of users"
+				" in courses of an institution",
+				"SELECT COUNT(DISTINCT crs_usr.UsrCod)"
+				" FROM centres,degrees,courses,crs_usr"
+				" WHERE centres.InsCod=%ld"
+				" AND centres.CtrCod=degrees.CtrCod"
+				" AND degrees.DegCod=courses.DegCod"
+				" AND courses.CrsCod=crs_usr.CrsCod"
+				" AND crs_usr.Role=%u",
+				InsCod,(unsigned) Role);
+   return NumUsrs;
   }
 
 /*****************************************************************************/
@@ -4053,29 +4090,37 @@ unsigned Usr_GetNumUsrsInCrssOfIns (Rol_Role_t Role,long InsCod)
 
 unsigned Usr_GetNumUsrsInCrssOfCty (Rol_Role_t Role,long CtyCod)
   {
+   unsigned NumUsrs;
+
    /***** Get the number of users in courses of a country from database ******/
    if (Role == Rol_UNK)	// Any user
-      DB_BuildQuery ("SELECT COUNT(DISTINCT crs_usr.UsrCod)"
-		     " FROM institutions,centres,degrees,courses,crs_usr"
-		     " WHERE institutions.CtyCod=%ld"
-		     " AND institutions.InsCod=centres.InsCod"
-		     " AND centres.CtrCod=degrees.CtrCod"
-		     " AND degrees.DegCod=courses.DegCod"
-		     " AND courses.CrsCod=crs_usr.CrsCod",
-		     CtyCod);
+      NumUsrs =
+      (unsigned) DB_QueryCOUNT ("can not get the number of users"
+				" in courses of a country",
+				"SELECT COUNT(DISTINCT crs_usr.UsrCod)"
+			        " FROM institutions,centres,degrees,courses,crs_usr"
+			        " WHERE institutions.CtyCod=%ld"
+			        " AND institutions.InsCod=centres.InsCod"
+			        " AND centres.CtrCod=degrees.CtrCod"
+			        " AND degrees.DegCod=courses.DegCod"
+			        " AND courses.CrsCod=crs_usr.CrsCod",
+			        CtyCod);
    else
       // This query is very slow.
       // It's a bad idea to get number of teachers or students for a big list of countries
-      DB_BuildQuery ("SELECT COUNT(DISTINCT crs_usr.UsrCod)"
-		     " FROM institutions,centres,degrees,courses,crs_usr"
-		     " WHERE institutions.CtyCod=%ld"
-		     " AND institutions.InsCod=centres.InsCod"
-		     " AND centres.CtrCod=degrees.CtrCod"
-		     " AND degrees.DegCod=courses.DegCod"
-		     " AND courses.CrsCod=crs_usr.CrsCod"
-		     " AND crs_usr.Role=%u",
-		     CtyCod,(unsigned) Role);
-   return (unsigned) DB_QueryCOUNT_new ("can not get the number of users in courses of a country");
+      NumUsrs =
+      (unsigned) DB_QueryCOUNT ("can not get the number of users"
+				" in courses of a country",
+				"SELECT COUNT(DISTINCT crs_usr.UsrCod)"
+				" FROM institutions,centres,degrees,courses,crs_usr"
+				" WHERE institutions.CtyCod=%ld"
+				" AND institutions.InsCod=centres.InsCod"
+				" AND centres.CtrCod=degrees.CtrCod"
+				" AND degrees.DegCod=courses.DegCod"
+				" AND courses.CrsCod=crs_usr.CrsCod"
+				" AND crs_usr.Role=%u",
+				CtyCod,(unsigned) Role);
+   return NumUsrs;
   }
 
 /*****************************************************************************/
@@ -4146,14 +4191,17 @@ unsigned Usr_GetNumTchsCurrentInsInDepartment (long DptCod)
   {
    /***** Get the number of teachers
           from the current institution in a department *****/
-   DB_BuildQuery ("SELECT COUNT(DISTINCT usr_data.UsrCod)"
-	          " FROM usr_data,crs_usr"
-                  " WHERE usr_data.InsCod=%ld AND usr_data.DptCod=%ld"
-                  " AND usr_data.UsrCod=crs_usr.UsrCod"
-                  " AND crs_usr.Role IN (%u,%u)",
-		  Gbl.CurrentIns.Ins.InsCod,DptCod,
-		  (unsigned) Rol_NET,(unsigned) Rol_TCH);
-   return (unsigned) DB_QueryCOUNT_new ("can not get the number of teachers in a department");
+   return
+   (unsigned) DB_QueryCOUNT ("can not get the number of teachers"
+			     " in a department",
+			     "SELECT COUNT(DISTINCT usr_data.UsrCod)"
+			     " FROM usr_data,crs_usr"
+			     " WHERE usr_data.InsCod=%ld"
+			     " AND usr_data.DptCod=%ld"
+			     " AND usr_data.UsrCod=crs_usr.UsrCod"
+			     " AND crs_usr.Role IN (%u,%u)",
+			     Gbl.CurrentIns.Ins.InsCod,DptCod,
+			     (unsigned) Rol_NET,(unsigned) Rol_TCH);
   }
 
 /*****************************************************************************/
@@ -4163,8 +4211,11 @@ unsigned Usr_GetNumTchsCurrentInsInDepartment (long DptCod)
 unsigned Usr_GetNumUsrsWhoClaimToBelongToCty (long CtyCod)
   {
    /***** Get the number of users in a country from database *****/
-   DB_BuildQuery ("SELECT COUNT(UsrCod) FROM usr_data WHERE CtyCod=%ld",CtyCod);
-   return (unsigned) DB_QueryCOUNT_new ("can not get the number of users in a country");
+   return
+   (unsigned) DB_QueryCOUNT ("can not get the number of users in a country",
+			     "SELECT COUNT(UsrCod) FROM usr_data"
+			     " WHERE CtyCod=%ld",
+			     CtyCod);
   }
 
 /*****************************************************************************/
@@ -4174,8 +4225,12 @@ unsigned Usr_GetNumUsrsWhoClaimToBelongToCty (long CtyCod)
 unsigned Usr_GetNumUsrsWhoClaimToBelongToIns (long InsCod)
   {
    /***** Get the number of users in an institution from database *****/
-   DB_BuildQuery ("SELECT COUNT(UsrCod) FROM usr_data WHERE InsCod=%ld",InsCod);
-   return (unsigned) DB_QueryCOUNT_new ("can not get the number of users in an institution");
+   return
+   (unsigned) DB_QueryCOUNT ("can not get the number of users"
+			     " in an institution",
+			     "SELECT COUNT(UsrCod) FROM usr_data"
+			     " WHERE InsCod=%ld",
+			     InsCod);
   }
 
 /*****************************************************************************/
@@ -4185,8 +4240,11 @@ unsigned Usr_GetNumUsrsWhoClaimToBelongToIns (long InsCod)
 unsigned Usr_GetNumUsrsWhoClaimToBelongToCtr (long CtrCod)
   {
    /***** Get the number of users in a centre from database *****/
-   DB_BuildQuery ("SELECT COUNT(UsrCod) FROM usr_data WHERE CtrCod=%ld",CtrCod);
-   return (unsigned) DB_QueryCOUNT_new ("can not get the number of users in a centre");
+   return
+   (unsigned) DB_QueryCOUNT ("can not get the number of users in a centre",
+			     "SELECT COUNT(UsrCod) FROM usr_data"
+			     " WHERE CtrCod=%ld",
+			     CtrCod);
   }
 
 /*****************************************************************************/
@@ -4196,12 +4254,14 @@ unsigned Usr_GetNumUsrsWhoClaimToBelongToCtr (long CtrCod)
 unsigned Usr_GetNumberOfTeachersInCentre (long CtrCod)
   {
    /***** Get the number of teachers in a centre from database *****/
-   DB_BuildQuery ("SELECT COUNT(DISTINCT usr_data.UsrCod)"
-	          " FROM usr_data,crs_usr"
-                  " WHERE usr_data.CtrCod=%ld"
-                  " AND usr_data.UsrCod=crs_usr.UsrCod AND crs_usr.Role=%u",
-		  CtrCod,(unsigned) Rol_TCH);
-   return (unsigned) DB_QueryCOUNT_new ("can not get the number of teachers in a centre");
+   return
+   (unsigned) DB_QueryCOUNT ("can not get the number of teachers in a centre",
+			     "SELECT COUNT(DISTINCT usr_data.UsrCod)"
+			     " FROM usr_data,crs_usr"
+			     " WHERE usr_data.CtrCod=%ld"
+			     " AND usr_data.UsrCod=crs_usr.UsrCod"
+			     " AND crs_usr.Role=%u",
+			     CtrCod,(unsigned) Rol_TCH);
   }
 
 /*****************************************************************************/
@@ -8437,8 +8497,10 @@ bool Usr_ChkIfUsrCodExists (long UsrCod)
       return false;
 
    /***** Get if a user exists in database *****/
-   DB_BuildQuery ("SELECT COUNT(*) FROM usr_data WHERE UsrCod=%ld",UsrCod);
-   return (DB_QueryCOUNT_new ("can not check if a user exists") != 0);
+   return (DB_QueryCOUNT ("can not check if a user exists",
+			  "SELECT COUNT(*) FROM usr_data"
+			  " WHERE UsrCod=%ld",
+			  UsrCod) != 0);
   }
 
 /*****************************************************************************/
@@ -8480,8 +8542,9 @@ void Usr_ShowWarningNoUsersFound (Rol_Role_t Role)
 unsigned Usr_GetTotalNumberOfUsersInPlatform (void)
   {
    /***** Get number of users from database *****/
-   DB_BuildQuery ("SELECT COUNT(UsrCod) FROM usr_data");
-   return (unsigned) DB_QueryCOUNT_new ("can not get number of users");
+   return
+   (unsigned) DB_QueryCOUNT ("can not get number of users",
+			     "SELECT COUNT(UsrCod) FROM usr_data");
   }
 
 /*****************************************************************************/
@@ -8499,6 +8562,7 @@ unsigned Usr_GetTotalNumberOfUsersInCourses (Sco_Scope_t Scope,unsigned Roles)
    Rol_Role_t FirstRoleRequested;
    bool MoreThanOneRole;
    bool FirstRole;
+   unsigned NumUsrs;
 
    /***** Reset roles that can not belong to courses.
           Only
@@ -8570,102 +8634,128 @@ unsigned Usr_GetTotalNumberOfUsersInCourses (Sco_Scope_t Scope,unsigned Roles)
      {
       case Sco_SCOPE_SYS:
          if (AnyUserInCourses)	// Any user
-            DB_BuildQuery ("SELECT COUNT(DISTINCT UsrCod)"
-        	           " FROM crs_usr");
+            NumUsrs =
+            (unsigned) DB_QueryCOUNT ("can not get number of users",
+        			      "SELECT COUNT(DISTINCT UsrCod)"
+        			      " FROM crs_usr");
          else
-            DB_BuildQuery ("SELECT COUNT(DISTINCT UsrCod)"
-        	           " FROM crs_usr WHERE Role%s",
-			   SubQueryRoles);
+            NumUsrs =
+            (unsigned) DB_QueryCOUNT ("can not get number of users",
+        			      "SELECT COUNT(DISTINCT UsrCod)"
+        			      " FROM crs_usr WHERE Role%s",
+				      SubQueryRoles);
          break;
       case Sco_SCOPE_CTY:
          if (AnyUserInCourses)	// Any user
-            DB_BuildQuery ("SELECT COUNT(DISTINCT crs_usr.UsrCod)"
-        	           " FROM institutions,centres,degrees,courses,crs_usr"
-                           " WHERE institutions.CtyCod=%ld"
-                           " AND institutions.InsCod=centres.InsCod"
-                           " AND centres.CtrCod=degrees.CtrCod"
-                           " AND degrees.DegCod=courses.DegCod"
-                           " AND courses.CrsCod=crs_usr.CrsCod",
-			   Gbl.CurrentCty.Cty.CtyCod);
+            NumUsrs =
+            (unsigned) DB_QueryCOUNT ("can not get number of users",
+        			      "SELECT COUNT(DISTINCT crs_usr.UsrCod)"
+				      " FROM institutions,centres,degrees,courses,crs_usr"
+				      " WHERE institutions.CtyCod=%ld"
+				      " AND institutions.InsCod=centres.InsCod"
+				      " AND centres.CtrCod=degrees.CtrCod"
+				      " AND degrees.DegCod=courses.DegCod"
+				      " AND courses.CrsCod=crs_usr.CrsCod",
+				      Gbl.CurrentCty.Cty.CtyCod);
          else
-            DB_BuildQuery ("SELECT COUNT(DISTINCT crs_usr.UsrCod)"
-        	           " FROM institutions,centres,degrees,courses,crs_usr"
-                           " WHERE institutions.CtyCod=%ld"
-                           " AND institutions.InsCod=centres.InsCod"
-                           " AND centres.CtrCod=degrees.CtrCod"
-                           " AND degrees.DegCod=courses.DegCod"
-                           " AND courses.CrsCod=crs_usr.CrsCod"
-                           " AND crs_usr.Role%s",
-			   Gbl.CurrentCty.Cty.CtyCod,SubQueryRoles);
+            NumUsrs =
+            (unsigned) DB_QueryCOUNT ("can not get number of users",
+        			      "SELECT COUNT(DISTINCT crs_usr.UsrCod)"
+				      " FROM institutions,centres,degrees,courses,crs_usr"
+				      " WHERE institutions.CtyCod=%ld"
+				      " AND institutions.InsCod=centres.InsCod"
+				      " AND centres.CtrCod=degrees.CtrCod"
+				      " AND degrees.DegCod=courses.DegCod"
+				      " AND courses.CrsCod=crs_usr.CrsCod"
+				      " AND crs_usr.Role%s",
+				      Gbl.CurrentCty.Cty.CtyCod,SubQueryRoles);
          break;
       case Sco_SCOPE_INS:
          if (AnyUserInCourses)	// Any user
-            DB_BuildQuery ("SELECT COUNT(DISTINCT crs_usr.UsrCod)"
-        	           " FROM centres,degrees,courses,crs_usr"
-                           " WHERE centres.InsCod=%ld"
-                           " AND centres.CtrCod=degrees.CtrCod"
-                           " AND degrees.DegCod=courses.DegCod"
-                           " AND courses.CrsCod=crs_usr.CrsCod",
-			   Gbl.CurrentIns.Ins.InsCod);
+            NumUsrs =
+            (unsigned) DB_QueryCOUNT ("can not get number of users",
+        			      "SELECT COUNT(DISTINCT crs_usr.UsrCod)"
+				      " FROM centres,degrees,courses,crs_usr"
+				      " WHERE centres.InsCod=%ld"
+				      " AND centres.CtrCod=degrees.CtrCod"
+				      " AND degrees.DegCod=courses.DegCod"
+				      " AND courses.CrsCod=crs_usr.CrsCod",
+				      Gbl.CurrentIns.Ins.InsCod);
          else
-            DB_BuildQuery ("SELECT COUNT(DISTINCT crs_usr.UsrCod)"
-        	           " FROM centres,degrees,courses,crs_usr"
-                           " WHERE centres.InsCod=%ld"
-                           " AND centres.CtrCod=degrees.CtrCod"
-                           " AND degrees.DegCod=courses.DegCod"
-                           " AND courses.CrsCod=crs_usr.CrsCod"
-                           " AND crs_usr.Role%s",
-			   Gbl.CurrentIns.Ins.InsCod,SubQueryRoles);
+            NumUsrs =
+            (unsigned) DB_QueryCOUNT ("can not get number of users",
+        			      "SELECT COUNT(DISTINCT crs_usr.UsrCod)"
+				      " FROM centres,degrees,courses,crs_usr"
+				      " WHERE centres.InsCod=%ld"
+				      " AND centres.CtrCod=degrees.CtrCod"
+				      " AND degrees.DegCod=courses.DegCod"
+				      " AND courses.CrsCod=crs_usr.CrsCod"
+				      " AND crs_usr.Role%s",
+				      Gbl.CurrentIns.Ins.InsCod,SubQueryRoles);
          break;
       case Sco_SCOPE_CTR:
          if (AnyUserInCourses)	// Any user
-            DB_BuildQuery ("SELECT COUNT(DISTINCT crs_usr.UsrCod)"
-        	           " FROM degrees,courses,crs_usr"
-                           " WHERE degrees.CtrCod=%ld"
-                           " AND degrees.DegCod=courses.DegCod"
-                           " AND courses.CrsCod=crs_usr.CrsCod",
-			   Gbl.CurrentCtr.Ctr.CtrCod);
+            NumUsrs =
+            (unsigned) DB_QueryCOUNT ("can not get number of users",
+        			      "SELECT COUNT(DISTINCT crs_usr.UsrCod)"
+				      " FROM degrees,courses,crs_usr"
+				      " WHERE degrees.CtrCod=%ld"
+				      " AND degrees.DegCod=courses.DegCod"
+				      " AND courses.CrsCod=crs_usr.CrsCod",
+				      Gbl.CurrentCtr.Ctr.CtrCod);
          else
-            DB_BuildQuery ("SELECT COUNT(DISTINCT crs_usr.UsrCod)"
-        	           " FROM degrees,courses,crs_usr"
-                           " WHERE degrees.CtrCod=%ld"
-                           " AND degrees.DegCod=courses.DegCod"
-                           " AND courses.CrsCod=crs_usr.CrsCod"
-                           " AND crs_usr.Role%s",
-			   Gbl.CurrentCtr.Ctr.CtrCod,SubQueryRoles);
+            NumUsrs =
+            (unsigned) DB_QueryCOUNT ("can not get number of users",
+        			      "SELECT COUNT(DISTINCT crs_usr.UsrCod)"
+				      " FROM degrees,courses,crs_usr"
+				      " WHERE degrees.CtrCod=%ld"
+				      " AND degrees.DegCod=courses.DegCod"
+				      " AND courses.CrsCod=crs_usr.CrsCod"
+				      " AND crs_usr.Role%s",
+				      Gbl.CurrentCtr.Ctr.CtrCod,SubQueryRoles);
          break;
       case Sco_SCOPE_DEG:
          if (AnyUserInCourses)	// Any user
-            DB_BuildQuery ("SELECT COUNT(DISTINCT crs_usr.UsrCod)"
-        	           " FROM courses,crs_usr"
-                           " WHERE courses.DegCod=%ld"
-                           " AND courses.CrsCod=crs_usr.CrsCod",
-			   Gbl.CurrentDeg.Deg.DegCod);
+            NumUsrs =
+            (unsigned) DB_QueryCOUNT ("can not get number of users",
+        			      "SELECT COUNT(DISTINCT crs_usr.UsrCod)"
+				      " FROM courses,crs_usr"
+				      " WHERE courses.DegCod=%ld"
+				      " AND courses.CrsCod=crs_usr.CrsCod",
+				      Gbl.CurrentDeg.Deg.DegCod);
          else
-            DB_BuildQuery ("SELECT COUNT(DISTINCT crs_usr.UsrCod)"
-        	           " FROM courses,crs_usr"
-                           " WHERE courses.DegCod=%ld"
-                           " AND courses.CrsCod=crs_usr.CrsCod"
-                           " AND crs_usr.Role%s",
-			   Gbl.CurrentDeg.Deg.DegCod,SubQueryRoles);
+            NumUsrs =
+            (unsigned) DB_QueryCOUNT ("can not get number of users",
+        			      "SELECT COUNT(DISTINCT crs_usr.UsrCod)"
+				      " FROM courses,crs_usr"
+				      " WHERE courses.DegCod=%ld"
+				      " AND courses.CrsCod=crs_usr.CrsCod"
+				      " AND crs_usr.Role%s",
+				      Gbl.CurrentDeg.Deg.DegCod,SubQueryRoles);
          break;
       case Sco_SCOPE_CRS:
          if (AnyUserInCourses)	// Any user
-            DB_BuildQuery ("SELECT COUNT(DISTINCT UsrCod) FROM crs_usr"
-                           " WHERE CrsCod=%ld",
-			   Gbl.CurrentCrs.Crs.CrsCod);
+            NumUsrs =
+            (unsigned) DB_QueryCOUNT ("can not get number of users",
+        			      "SELECT COUNT(DISTINCT UsrCod) FROM crs_usr"
+				      " WHERE CrsCod=%ld",
+				      Gbl.CurrentCrs.Crs.CrsCod);
          else
-            DB_BuildQuery ("SELECT COUNT(DISTINCT UsrCod) FROM crs_usr"
-                           " WHERE CrsCod=%ld"
-                           " AND Role%s",
-			   Gbl.CurrentCrs.Crs.CrsCod,SubQueryRoles);
+            NumUsrs =
+            (unsigned) DB_QueryCOUNT ("can not get number of users",
+        			      "SELECT COUNT(DISTINCT UsrCod)"
+        			      " FROM crs_usr"
+				      " WHERE CrsCod=%ld"
+				      " AND Role%s",
+				      Gbl.CurrentCrs.Crs.CrsCod,SubQueryRoles);
          break;
       default:
 	 Lay_WrongScopeExit ();
+	 NumUsrs = 0;	// Not reached. Initialized to avoid warning.
 	 break;
      }
 
-   return (unsigned) DB_QueryCOUNT_new ("can not get number of users");
+   return NumUsrs;
   }
 
 /*****************************************************************************/
@@ -8675,9 +8765,11 @@ unsigned Usr_GetTotalNumberOfUsersInCourses (Sco_Scope_t Scope,unsigned Roles)
 unsigned Usr_GetNumUsrsNotBelongingToAnyCrs (void)
   {
    /***** Get number of users who are in table of users but not in table courses-users *****/
-   DB_BuildQuery ("SELECT COUNT(*) FROM usr_data WHERE UsrCod NOT IN"
-                  " (SELECT DISTINCT(UsrCod) FROM crs_usr)");
-   return (unsigned) DB_QueryCOUNT_new ("can not get number of users who do not belong to any course");
+   return
+   (unsigned) DB_QueryCOUNT ("can not get number of users"
+			     " who do not belong to any course",
+			     "SELECT COUNT(*) FROM usr_data WHERE UsrCod NOT IN"
+			     " (SELECT DISTINCT(UsrCod) FROM crs_usr)");
   }
 
 /*****************************************************************************/
@@ -8990,8 +9082,9 @@ float Usr_GetNumUsrsPerCrs (Rol_Role_t Role)
 
 bool Usr_CheckIfUsrBanned (long UsrCod)
   {
-   DB_BuildQuery ("SELECT COUNT(*) FROM usr_banned WHERE UsrCod=%ld",UsrCod);
-   return (DB_QueryCOUNT_new ("can not check if user is banned") != 0);
+   return (DB_QueryCOUNT ("can not check if user is banned",
+			  "SELECT COUNT(*) FROM usr_banned WHERE UsrCod=%ld",
+			  UsrCod) != 0);
   }
 
 /*****************************************************************************/
diff --git a/swad_web_service.c b/swad_web_service.c
index b54296a00..eca4a29a8 100644
--- a/swad_web_service.c
+++ b/swad_web_service.c
@@ -357,9 +357,9 @@ static int Svc_CheckIdSession (const char *IdSession)
      }
 
    /***** Query if session identifier already exists in database *****/
-   DB_BuildQuery ("SELECT COUNT(*) FROM sessions WHERE SessionId='%s'",
-                  IdSession);
-   if (DB_QueryCOUNT_new ("can not get session data") != 1)
+   if (DB_QueryCOUNT ("can not get session data",
+		      "SELECT COUNT(*) FROM sessions WHERE SessionId='%s'",
+                      IdSession) != 1)
       return soap_receiver_fault (Gbl.soap,
 	                          "Bad session identifier",
 	                          "Session identifier does not exist in database");
@@ -412,8 +412,9 @@ static int Svc_CheckCourseAndGroupCodes (long CrsCod,long GrpCod)
 	                        "Course code must be a integer greater than 0");
 
    /***** Query if course code already exists in database *****/
-   DB_BuildQuery ("SELECT COUNT(*) FROM courses WHERE CrsCod=%ld",CrsCod);
-   if (DB_QueryCOUNT_new ("can not get course") != 1)
+   if (DB_QueryCOUNT ("can not get course",
+		      "SELECT COUNT(*) FROM courses WHERE CrsCod=%ld",
+		      CrsCod) != 1)
       return soap_sender_fault (Gbl.soap,
 	                        "Bad course code",
 	                        "Course code does not exist in database");
@@ -422,12 +423,12 @@ static int Svc_CheckCourseAndGroupCodes (long CrsCod,long GrpCod)
    if (GrpCod > 0)	// <=0 means "the whole course"
      {
       /***** Query if group code already exists in database *****/
-      DB_BuildQuery ("SELECT COUNT(*) FROM crs_grp_types,crs_grp"
-                     " WHERE crs_grp_types.CrsCod=%ld"
-                     " AND crs_grp_types.GrpTypCod=crs_grp.GrpTypCod"
-                     " AND crs_grp.GrpCod=%ld",
-		     CrsCod,GrpCod);
-      if (DB_QueryCOUNT_new ("can not get group") != 1)
+      if (DB_QueryCOUNT ("can not get group",
+			 "SELECT COUNT(*) FROM crs_grp_types,crs_grp"
+			 " WHERE crs_grp_types.CrsCod=%ld"
+			 " AND crs_grp_types.GrpTypCod=crs_grp.GrpTypCod"
+			 " AND crs_grp.GrpCod=%ld",
+			 CrsCod,GrpCod) != 1)
          return soap_sender_fault (Gbl.soap,
                                    "Bad group code",
                                    "Group code does not exist in database or it's not a group of the specified course");
@@ -454,8 +455,9 @@ static int Svc_GenerateNewWSKey (long UsrCod,
              Svc_BYTES_WS_KEY);
 
    /***** Check that key does not exist in database *****/
-   DB_BuildQuery ("SELECT COUNT(*) FROM ws_keys WHERE WSKey='%s'",WSKey);
-   if (DB_QueryCOUNT_new ("can not get existence of key"))
+   if (DB_QueryCOUNT ("can not get existence of key",
+		      "SELECT COUNT(*) FROM ws_keys WHERE WSKey='%s'",
+		      WSKey))
       return soap_receiver_fault (Gbl.soap,
 	                          "Error when generating key",
 	                          "Generated key already existed in database");
@@ -743,9 +745,10 @@ static int Svc_CheckParamsNewAccount (char *NewNicknameWithArroba,	// Input
       Str_RemoveLeadingArrobas (NewNicknameWithoutArroba);
 
       /***** Check if the new nickname matches any of the nicknames of other users *****/
-      DB_BuildQuery ("SELECT COUNT(*) FROM usr_nicknames WHERE Nickname='%s'",
-		     NewNicknameWithoutArroba);
-      if (DB_QueryCOUNT_new ("can not check if nickname already existed"))        // A nickname of another user is the same that this nickname
+      if (DB_QueryCOUNT ("can not check if nickname already existed",
+			 "SELECT COUNT(*) FROM usr_nicknames"
+			 " WHERE Nickname='%s'",
+			 NewNicknameWithoutArroba))	// A nickname of another user is the same that this nickname
 	 return Svc_CHECK_NEW_ACCOUNT_NICKNAME_REGISTERED_BY_ANOTHER_USER;
      }
    else        // New nickname is not valid
@@ -755,10 +758,10 @@ static int Svc_CheckParamsNewAccount (char *NewNicknameWithArroba,	// Input
    if (Mai_CheckIfEmailIsValid (NewEmail))	// New email is valid
      {
       /***** Check if the new email matches any of the confirmed emails of other users *****/
-      DB_BuildQuery ("SELECT COUNT(*) FROM usr_emails"
-		     " WHERE E_mail='%s' AND Confirmed='Y'",
-		     NewEmail);
-      if (DB_QueryCOUNT_new ("can not check if email already existed"))	// An email of another user is the same that my email
+      if (DB_QueryCOUNT ("can not check if email already existed",
+			 "SELECT COUNT(*) FROM usr_emails"
+			 " WHERE E_mail='%s' AND Confirmed='Y'",
+			 NewEmail))	// An email of another user is the same that my email
 	 return Svc_CHECK_NEW_ACCOUNT_EMAIL_REGISTERED_BY_ANOTHER_USER;
      }
    else	// New email is not valid
@@ -3662,18 +3665,23 @@ static int Svc_GetNumTestQuestionsInCrs (long CrsCod)
    /***** Get number of questions *****/
    // Reject questions with any tag hidden
    // Select only questions with tags
-   DB_BuildQuery ("SELECT COUNT(*)"
-		  " FROM tst_questions,tst_question_tags,tst_tags"
-		  " WHERE tst_questions.CrsCod=%ld"
-                  " AND tst_questions.QstCod NOT IN"
-		  " (SELECT tst_question_tags.QstCod FROM tst_tags,tst_question_tags"
-		  " WHERE tst_tags.CrsCod=%ld AND tst_tags.TagHidden='Y'"
-		  " AND tst_tags.TagCod=tst_question_tags.TagCod)"
-		  " AND tst_questions.QstCod=tst_question_tags.QstCod"
-		  " AND tst_question_tags.TagCod=tst_tags.TagCod"
-		  " AND tst_tags.CrsCod=%ld",
-		  CrsCod,CrsCod,CrsCod);
-   return (int) DB_QueryCOUNT_new ("can not get number of test questions");
+   return
+   (int) DB_QueryCOUNT ("can not get number of test questions",
+			"SELECT COUNT(*)"
+			" FROM tst_questions,tst_question_tags,tst_tags"
+			" WHERE tst_questions.CrsCod=%ld"
+			" AND tst_questions.QstCod NOT IN"
+
+			" (SELECT tst_question_tags.QstCod"
+			" FROM tst_tags,tst_question_tags"
+			" WHERE tst_tags.CrsCod=%ld"
+			" AND tst_tags.TagHidden='Y'"
+			" AND tst_tags.TagCod=tst_question_tags.TagCod)"
+
+			" AND tst_questions.QstCod=tst_question_tags.QstCod"
+			" AND tst_question_tags.TagCod=tst_tags.TagCod"
+			" AND tst_tags.CrsCod=%ld",
+			CrsCod,CrsCod,CrsCod);
   }
 
 /*****************************************************************************/