Version19.112.9

swad_API.c

@@ -1032,7 +1032,7 @@ int swad__loginBySessionKey (struct soap *soap,
 
       /***** Get course (row[2]) *****/
       Gbl.Hierarchy.Crs.CrsCod = Str_ConvertStrCodToLongCod (row[2]);
-      Crs_GetDataOfCourseByCod (&Gbl.Hierarchy.Crs,Crs_GET_BASIC_DATA);
+      Crs_GetDataOfCourseByCod (&Gbl.Hierarchy.Crs);
       loginBySessionKeyOut->courseCode = (int) Gbl.Hierarchy.Crs.CrsCod;
       Str_Copy (loginBySessionKeyOut->courseName,Gbl.Hierarchy.Crs.FullName,
                 Hie_MAX_BYTES_FULL_NAME);
@@ -3013,7 +3013,7 @@ int swad__getNotifications (struct soap *soap,
 
          /* Get course (row[7]) */
          Crs.CrsCod = Str_ConvertStrCodToLongCod (row[7]);
-         Crs_GetDataOfCourseByCod (&Crs,Crs_GET_BASIC_DATA);
+         Crs_GetDataOfCourseByCod (&Crs);
 
          /* Get user's code of the user who caused the event (row[3]) */
          Gbl.Usrs.Other.UsrDat.UsrCod = Str_ConvertStrCodToLongCod (row[3]);

swad_changelog.h

@@ -492,7 +492,7 @@ enscript -2 --landscape --color --file-align=2 --highlight --line-numbers -o - *
 En OpenSWAD:
 ps2pdf source.ps destination.pdf
 */
-#define Log_PLATFORM_VERSION	"SWAD 19.112.8 (2020-01-05)"
+#define Log_PLATFORM_VERSION	"SWAD 19.112.9 (2020-01-05)"
 #define CSS_FILE		"swad19.112.css"
 #define JS_FILE			"swad19.91.1.js"
 /*
@@ -501,7 +501,9 @@ ps2pdf source.ps destination.pdf
 // TODO: No se puede entrar con DNI '1' suponiendo que no tenga password ¿por qué?
 // TODO: Mapas más estrechos en móvil
 // TODO: Quitar todos los EXTRA_DATA.
+// TODO: ¿ Cachear Usr_GetNumUsrsInCrssOfDeg ?
 
+	Version 19.112.9: Jan 05, 2020	Optimization in number of users in a course. (278419 lines)
 	Version 19.112.8: Jan 05, 2020	Optimization in number of courses in a degree. (278396 lines)
 	Version 19.112.7: Jan 05, 2020	Optimization in number of degrees in a centre. (278384 lines)
 	Version 19.112.6: Jan 05, 2020	Optimization in number of courses in a centre. (278374 lines)

swad_chat.c

@@ -206,7 +206,7 @@ void Cht_ShowListOfAvailableChatRooms (void)
 	    if ((Crs.CrsCod = Str_ConvertStrCodToLongCod (row[0])) > 0)
 	      {
                /* Get data of this course */
-               Crs_GetDataOfCourseByCod (&Crs,Crs_GET_BASIC_DATA);
+               Crs_GetDataOfCourseByCod (&Crs);
 
                /* Link to the room of this course */
                IsLastItemInLevel[2] = (NumRow == NumRows - 1);
@@ -557,7 +557,7 @@ void Cht_OpenChatWindow (void)
 
          /* Get data of this course */
          Crs.CrsCod = Gbl.Usrs.Me.MyCrss.Crss[NumMyCrs].CrsCod;
-         Crs_GetDataOfCourseByCod (&Crs,Crs_GET_BASIC_DATA);
+         Crs_GetDataOfCourseByCod (&Crs);
 
          snprintf (ThisRoomShortName,sizeof (ThisRoomShortName),
                    "%s",

swad_course.c

@@ -343,7 +343,7 @@ static void Crs_WriteListMyCoursesToSelectOne (void)
 
 		  /***** Get data of this course *****/
 		  Crs.CrsCod = Str_ConvertStrCodToLongCod (row[0]);
-		  if (!Crs_GetDataOfCourseByCod (&Crs,Crs_GET_BASIC_DATA))
+		  if (!Crs_GetDataOfCourseByCod (&Crs))
 		     Lay_ShowErrorAndExit ("Course not found.");
 
 		  /***** Write link to course *****/
@@ -658,14 +658,6 @@ static void Crs_GetListCrssInCurrentDeg (Crs_WhatCourses_t WhatCourses)
          /* Get next course */
          row = mysql_fetch_row (mysql_res);
          Crs_GetDataOfCourseFromRow (Crs,row);
-
-	 /* Get number of users in this course */
-	 Crs->NumUsrs[Rol_STD] = Usr_GetNumUsrsInCrs (Rol_STD,Crs->CrsCod);
-	 Crs->NumUsrs[Rol_NET] = Usr_GetNumUsrsInCrs (Rol_NET,Crs->CrsCod);
-	 Crs->NumUsrs[Rol_TCH] = Usr_GetNumUsrsInCrs (Rol_TCH,Crs->CrsCod);
-	 Crs->NumUsrs[Rol_UNK] = Crs->NumUsrs[Rol_STD] +
-				 Crs->NumUsrs[Rol_NET] +
-				 Crs->NumUsrs[Rol_TCH];
         }
      }
 
@@ -865,6 +857,7 @@ static bool Crs_ListCoursesOfAYearForSeeing (unsigned Year)
    const char *BgColor;
    Crs_StatusTxt_t StatusTxt;
    bool ThisYearHasCourses = false;
+   unsigned NumUsrs[Rol_NUM_ROLES];
 
    /***** Write all the courses of this year *****/
    for (NumCrs = 0;
@@ -892,13 +885,19 @@ static bool Crs_ListCoursesOfAYearForSeeing (unsigned Year)
 
 	 HTM_TR_Begin (NULL);
 
+	 /* Get number of users */
+	 NumUsrs[Rol_UNK] = Usr_GetNumUsrsInCrs (Rol_UNK,Crs->CrsCod);
+	 NumUsrs[Rol_STD] = Usr_GetNumUsrsInCrs (Rol_STD,Crs->CrsCod);
+	 NumUsrs[Rol_NET] = Usr_GetNumUsrsInCrs (Rol_NET,Crs->CrsCod);
+	 NumUsrs[Rol_TCH] = Usr_GetNumUsrsInCrs (Rol_TCH,Crs->CrsCod);
+
 	 /* Put green tip if course has users */
 	 HTM_TD_Begin ("class=\"%s CM %s\" title=\"%s\"",
 		       TxtClassNormal,BgColor,
-		       Crs->NumUsrs[Rol_UNK] ? Txt_COURSE_With_users :
+		       NumUsrs[Rol_UNK] ? Txt_COURSE_With_users :
-					       Txt_COURSE_Without_users);
+				          Txt_COURSE_Without_users);
-	 HTM_Txt (Crs->NumUsrs[Rol_UNK] ? "✓" :
+	 HTM_Txt (NumUsrs[Rol_UNK] ? "✓" :
-				          " ");
+			             " ");
 	 HTM_TD_End ();
 
 	 /* Institutional code of the course */
@@ -925,13 +924,13 @@ static bool Crs_ListCoursesOfAYearForSeeing (unsigned Year)
 
 	 /* Current number of teachers in this course */
 	 HTM_TD_Begin ("class=\"%s RM %s\"",TxtClassNormal,BgColor);
-	 HTM_Unsigned (Crs->NumUsrs[Rol_TCH] +
+	 HTM_Unsigned (NumUsrs[Rol_TCH] +
-		       Crs->NumUsrs[Rol_NET]);
+		       NumUsrs[Rol_NET]);
 	 HTM_TD_End ();
 
 	 /* Current number of students in this course */
 	 HTM_TD_Begin ("class=\"%s RM %s\"",TxtClassNormal,BgColor);
-	 HTM_Unsigned (Crs->NumUsrs[Rol_STD]);
+	 HTM_Unsigned (NumUsrs[Rol_STD]);
 	 HTM_TD_End ();
 
 	 /* Course status */
@@ -1065,6 +1064,7 @@ static void Crs_ListCoursesOfAYearForEdition (unsigned Year)
    unsigned NumCrs;
    struct UsrData UsrDat;
    bool ICanEdit;
+   unsigned NumUsrs[Rol_NUM_ROLES];
    Crs_StatusTxt_t StatusTxt;
    unsigned StatusUnsigned;
 
@@ -1081,11 +1081,17 @@ static void Crs_ListCoursesOfAYearForEdition (unsigned Year)
 	{
 	 ICanEdit = Crs_CheckIfICanEdit (Crs);
 
+	 /* Get number of users */
+	 NumUsrs[Rol_UNK] = Usr_GetNumUsrsInCrs (Rol_UNK,Crs->CrsCod);
+	 NumUsrs[Rol_STD] = Usr_GetNumUsrsInCrs (Rol_STD,Crs->CrsCod);
+	 NumUsrs[Rol_NET] = Usr_GetNumUsrsInCrs (Rol_NET,Crs->CrsCod);
+	 NumUsrs[Rol_TCH] = Usr_GetNumUsrsInCrs (Rol_TCH,Crs->CrsCod);
+
 	 HTM_TR_Begin (NULL);
 
 	 /* Put icon to remove course */
 	 HTM_TD_Begin ("class=\"BM\"");
-	 if (Crs->NumUsrs[Rol_UNK] ||	// Course has users ==> deletion forbidden
+	 if (NumUsrs[Rol_UNK] ||	// Course has users ==> deletion forbidden
 	     !ICanEdit)
 	    Ico_PutIconRemovalNotAllowed ();
 	 else	// Crs->NumUsrs == 0 && ICanEdit
@@ -1168,13 +1174,13 @@ static void Crs_ListCoursesOfAYearForEdition (unsigned Year)
 
 	 /* Current number of teachers in this course */
 	 HTM_TD_Begin ("class=\"DAT RM\"");
-	 HTM_Unsigned (Crs->NumUsrs[Rol_TCH] +
+	 HTM_Unsigned (NumUsrs[Rol_TCH] +
-		       Crs->NumUsrs[Rol_NET]);
+		       NumUsrs[Rol_NET]);
 	 HTM_TD_End ();
 
 	 /* Current number of students in this course */
 	 HTM_TD_Begin ("class=\"DAT RM\"");
-	 HTM_Unsigned (Crs->NumUsrs[Rol_STD]);
+	 HTM_Unsigned (NumUsrs[Rol_STD]);
 	 HTM_TD_End ();
 
 	 /* Course requester */
@@ -1567,14 +1573,15 @@ void Crs_RemoveCourse (void)
    Crs_EditingCrs->CrsCod = Crs_GetAndCheckParamOtherCrsCod (1);
 
    /***** Get data of the course from database *****/
-   Crs_GetDataOfCourseByCod (Crs_EditingCrs,Crs_GET_EXTRA_DATA);
+   Crs_GetDataOfCourseByCod (Crs_EditingCrs);
 
    if (Crs_CheckIfICanEdit (Crs_EditingCrs))
      {
       /***** Check if this course has users *****/
-      if (Crs_EditingCrs->NumUsrs[Rol_UNK])	// Course has users ==> don't remove
+      if (Usr_GetNumUsrsInCrs (Rol_UNK,Crs_EditingCrs->CrsCod))	// Course has users ==> don't remove
-         Ale_ShowAlert (Ale_WARNING,Txt_To_remove_a_course_you_must_first_remove_all_users_in_the_course);
+         Ale_ShowAlert (Ale_WARNING,
-      else			// Course has no users ==> remove it
+			Txt_To_remove_a_course_you_must_first_remove_all_users_in_the_course);
+      else	// Course has no users ==> remove it
         {
          /***** Remove course *****/
          Crs_RemoveCourseCompletely (Crs_EditingCrs->CrsCod);
@@ -1594,8 +1601,7 @@ void Crs_RemoveCourse (void)
 /********************* Get data of a course from its code ********************/
 /*****************************************************************************/
 
-bool Crs_GetDataOfCourseByCod (struct Course *Crs,
+bool Crs_GetDataOfCourseByCod (struct Course *Crs)
-                               Crs_GetExtraData_t GetExtraData)
   {
    MYSQL_RES *mysql_res;
    MYSQL_ROW row;
@@ -1608,10 +1614,6 @@ bool Crs_GetDataOfCourseByCod (struct Course *Crs,
    Crs->RequesterUsrCod = -1L;
    Crs->ShrtName[0] = '\0';
    Crs->FullName[0] = '\0';
-   Crs->NumUsrs[Rol_UNK] =
-   Crs->NumUsrs[Rol_STD] =
-   Crs->NumUsrs[Rol_NET] =
-   Crs->NumUsrs[Rol_TCH] = 0;
 
    /***** Check if course code is correct *****/
    if (Crs->CrsCod > 0)
@@ -1633,18 +1635,6 @@ bool Crs_GetDataOfCourseByCod (struct Course *Crs,
 	 row = mysql_fetch_row (mysql_res);
 	 Crs_GetDataOfCourseFromRow (Crs,row);
 
-	 /* Get extra data */
-	 if (GetExtraData == Crs_GET_EXTRA_DATA)
-	   {
-	    /* Get number of users in this course */
-	    Crs->NumUsrs[Rol_STD] = Usr_GetNumUsrsInCrs (Rol_STD,Crs->CrsCod);
-	    Crs->NumUsrs[Rol_NET] = Usr_GetNumUsrsInCrs (Rol_NET,Crs->CrsCod);
-	    Crs->NumUsrs[Rol_TCH] = Usr_GetNumUsrsInCrs (Rol_TCH,Crs->CrsCod);
-	    Crs->NumUsrs[Rol_UNK] = Crs->NumUsrs[Rol_STD] +
-				    Crs->NumUsrs[Rol_NET] +
-				    Crs->NumUsrs[Rol_TCH];
-	   }
-
          /* Set return value */
 	 CrsFound = true;
 	}
@@ -1749,6 +1739,9 @@ void Crs_RemoveCourseCompletely (long CrsCod)
       DB_QueryDELETE ("can not remove a course",
 		      "DELETE FROM courses WHERE CrsCod=%ld",
 		      CrsCod);
+
+      /***** Flush caches *****/
+      Usr_FlushCacheNumUsrsInCrs ();
      }
   }
 
@@ -1767,7 +1760,7 @@ static void Crs_EmptyCourseCompletely (long CrsCod)
      {
       /***** Get course data *****/
       Crs.CrsCod = CrsCod;
-      Crs_GetDataOfCourseByCod (&Crs,Crs_GET_EXTRA_DATA);
+      Crs_GetDataOfCourseByCod (&Crs);
 
       /***** Remove all the students in the course *****/
       Enr_RemAllStdsInCrs (&Crs);
@@ -1923,7 +1916,7 @@ void Crs_ChangeInsCrsCod (void)
    Par_GetParToText ("InsCrsCod",NewInstitutionalCrsCod,Crs_MAX_BYTES_INSTITUTIONAL_CRS_COD);
 
    /* Get data of the course */
-   Crs_GetDataOfCourseByCod (Crs_EditingCrs,Crs_GET_BASIC_DATA);
+   Crs_GetDataOfCourseByCod (Crs_EditingCrs);
 
    if (Crs_CheckIfICanEdit (Crs_EditingCrs))
      {
@@ -1969,7 +1962,7 @@ void Crs_ChangeCrsYear (void)
    Par_GetParToText ("OthCrsYear",YearStr,2);
    NewYear = Deg_ConvStrToYear (YearStr);
 
-   Crs_GetDataOfCourseByCod (Crs_EditingCrs,Crs_GET_BASIC_DATA);
+   Crs_GetDataOfCourseByCod (Crs_EditingCrs);
 
    if (Crs_CheckIfICanEdit (Crs_EditingCrs))
      {
@@ -2100,7 +2093,7 @@ void Crs_RenameCourse (struct Course *Crs,Cns_ShrtOrFullName_t ShrtOrFullName)
    Par_GetParToText (ParamName,NewCrsName,MaxBytes);
 
    /***** Get from the database the data of the degree *****/
-   Crs_GetDataOfCourseByCod (Crs,Crs_GET_BASIC_DATA);
+   Crs_GetDataOfCourseByCod (Crs);
 
    if (Crs_CheckIfICanEdit (Crs))
      {
@@ -2201,7 +2194,7 @@ void Crs_ChangeCrsStatus (void)
    Status = Crs_GetStatusBitsFromStatusTxt (StatusTxt);	// New status
 
    /***** Get data of course *****/
-   Crs_GetDataOfCourseByCod (Crs_EditingCrs,Crs_GET_BASIC_DATA);
+   Crs_GetDataOfCourseByCod (Crs_EditingCrs);
 
    /***** Update status in table of courses *****/
    DB_QueryUPDATE ("can not update the status of a course",
@@ -2838,8 +2831,6 @@ void Crs_RemoveOldCrss (void)
 
 static void Crs_EditingCourseConstructor (void)
   {
-   Rol_Role_t Role;
-
    /***** Pointer must be NULL *****/
    if (Crs_EditingCrs != NULL)
       Lay_ShowErrorAndExit ("Error initializing course.");
@@ -2856,10 +2847,6 @@ static void Crs_EditingCourseConstructor (void)
    Crs_EditingCrs->Status      = 0;
    Crs_EditingCrs->ShrtName[0] = '\0';
    Crs_EditingCrs->FullName[0] = '\0';
-   for (Role  = (Rol_Role_t) 0;
-	Role <= (Rol_Role_t) (Rol_NUM_ROLES - 1);
-	Role++)
-      Crs_EditingCrs->NumUsrs[Role] = 0;
   }
 
 static void Crs_EditingCourseDestructor (void)

swad_course.h

@@ -85,15 +85,8 @@ struct Course
    long RequesterUsrCod;			// User code of the person who requested the creation of this course
    char ShrtName[Hie_MAX_BYTES_SHRT_NAME + 1];	// Short name of course
    char FullName[Hie_MAX_BYTES_FULL_NAME + 1];	// Full name of course
-   unsigned NumUsrs[Rol_NUM_ROLES];		// Number of users
   };
 
-typedef enum
-  {
-   Crs_GET_BASIC_DATA,
-   Crs_GET_EXTRA_DATA,
-  } Crs_GetExtraData_t;
-
 /*****************************************************************************/
 /***************************** Public prototypes *****************************/
 /*****************************************************************************/
@@ -120,8 +113,7 @@ void Crs_RecFormReqCrs (void);
 void Crs_RecFormNewCrs (void);
 
 void Crs_RemoveCourse (void);
-bool Crs_GetDataOfCourseByCod (struct Course *Crs,
+bool Crs_GetDataOfCourseByCod (struct Course *Crs);
-                               Crs_GetExtraData_t GetExtraData);
 void Crs_RemoveCourseCompletely (long CrsCod);
 void Crs_ChangeInsCrsCod (void);
 void Crs_ChangeCrsYear (void);

swad_course_config.c

@@ -427,7 +427,7 @@ static void CrsCfg_NumUsrsInCrs (Rol_Role_t Role)
 
    /* Data */
    HTM_TD_Begin ("class=\"DAT LB\"");
-   HTM_Unsigned (Gbl.Hierarchy.Crs.NumUsrs[Role]);
+   HTM_Unsigned (Usr_GetNumUsrsInCrs (Role,Gbl.Hierarchy.Crs.CrsCod));
    HTM_TD_End ();
 
    HTM_TR_End ();

swad_enrolment.c

@@ -184,7 +184,7 @@ void Enr_CheckStdsAndPutButtonToRegisterStdsInCurrentCrs (void)
   {
    /***** Put link to register students *****/
    if (Gbl.Usrs.Me.Role.Logged == Rol_TCH)	// Course selected and I am logged as teacher
-      if (!Gbl.Hierarchy.Crs.NumUsrs[Rol_STD])	// No students in course
+      if (!Usr_GetNumUsrsInCrs (Rol_STD,Gbl.Hierarchy.Crs.CrsCod))	// No students in course
           Usr_ShowWarningNoUsersFound (Rol_STD);
   }
 
@@ -675,7 +675,7 @@ static void Enr_ShowFormRegRemSeveralUsrs (Rol_Role_t Role)
             Enr_PutLinkToAdminOneUsr (ActReqMdfOneStd);
 
             /* Put link to remove all the students in the current course */
-            if (Gbl.Hierarchy.Crs.NumUsrs[Rol_STD])	// This course has students
+            if (Usr_GetNumUsrsInCrs (Rol_STD,Gbl.Hierarchy.Crs.CrsCod))	// This course has students
                Enr_PutLinkToRemAllStdsThisCrs ();
 	    break;
 	 case Rol_NET:
@@ -1821,17 +1821,18 @@ void Enr_AskRemAllStdsThisCrs (void)
    extern const char *Hlp_USERS_Administration_remove_all_students;
    extern const char *Txt_Remove_all_students;
    extern const char *Txt_Do_you_really_want_to_remove_the_X_students_from_the_course_Y_;
+   unsigned NumStds = Usr_GetNumUsrsInCrs (Rol_STD,Gbl.Hierarchy.Crs.CrsCod);
 
    /***** Begin box *****/
    Box_BoxBegin (NULL,Txt_Remove_all_students,NULL,
                  Hlp_USERS_Administration_remove_all_students,Box_NOT_CLOSABLE);
 
-   if (Gbl.Hierarchy.Crs.NumUsrs[Rol_STD])
+   if (NumStds)
      {
       /***** Show question and button to remove students *****/
       /* Start alert */
       Ale_ShowAlertAndButton1 (Ale_QUESTION,Txt_Do_you_really_want_to_remove_the_X_students_from_the_course_Y_,
-                               Gbl.Hierarchy.Crs.NumUsrs[Rol_STD],
+                               NumStds,
                                Gbl.Hierarchy.Crs.FullName);
 
       /* Show form to request confirmation */
@@ -2002,9 +2003,9 @@ void Enr_SignUpInCrs (void)
       /***** Notify teachers or admins by email about the new enrolment request *****/
       // If this course has teachers ==> send notification to teachers
       // If this course has no teachers and I want to be a teacher ==> send notification to administrators or superusers
-      if (Gbl.Hierarchy.Crs.NumUsrs[Rol_TCH] ||
+      if (RoleFromForm == Rol_TCH)	// TODO: What happens in user wants to enrole as a non-editing teacher?
-	  RoleFromForm == Rol_TCH)
+	 if (Usr_GetNumUsrsInCrs (Rol_TCH,Gbl.Hierarchy.Crs.CrsCod))
-         Ntf_StoreNotifyEventsToAllUsrs (Ntf_EVENT_ENROLMENT_REQUEST,ReqCod);
+            Ntf_StoreNotifyEventsToAllUsrs (Ntf_EVENT_ENROLMENT_REQUEST,ReqCod);
      }
   }
 
@@ -2820,7 +2821,7 @@ static void Enr_ShowEnrolmentRequestsGivenRoles (unsigned RolesSelected)
 	    HTM_TD_End ();
 
             /***** Link to course *****/
-            Crs_GetDataOfCourseByCod (&Crs,Crs_GET_BASIC_DATA);
+            Crs_GetDataOfCourseByCod (&Crs);
             Deg.DegCod = Crs.DegCod;
             Deg_GetDataOfDegreeByCod (&Deg);
             HTM_TD_Begin ("class=\"DAT LT\"");
@@ -2836,7 +2837,7 @@ static void Enr_ShowEnrolmentRequestsGivenRoles (unsigned RolesSelected)
 
             /***** Number of teachers in the course *****/
             HTM_TD_Begin ("class=\"DAT RT\"");
-            HTM_Unsigned (Crs.NumUsrs[Rol_TCH]);
+            HTM_Unsigned (Usr_GetNumUsrsInCrs (Rol_TCH,Crs.CrsCod));
             HTM_TD_End ();
 
             /***** User photo *****/

swad_exam.c

@@ -1607,7 +1607,7 @@ static void Exa_GetNotifContentExamAnnouncement (char **ContentStr)
 
    /***** Get data of course *****/
    Crs.CrsCod = Gbl.ExamAnns.ExaDat.CrsCod;
-   Crs_GetDataOfCourseByCod (&Crs,Crs_GET_BASIC_DATA);
+   Crs_GetDataOfCourseByCod (&Crs);
 
    /***** Get data of degree *****/
    Deg.DegCod = Crs.DegCod;

swad_file_browser.c

@@ -6898,7 +6898,7 @@ static void Brw_WriteCurrentClipboard (void)
          break;
       case Brw_ADMI_DOC_CRS:
 	 Crs.CrsCod = Gbl.FileBrowser.Clipboard.Cod;
-	 Crs_GetDataOfCourseByCod (&Crs,Crs_GET_BASIC_DATA);
+	 Crs_GetDataOfCourseByCod (&Crs);
          snprintf (TxtClipboardZone,sizeof (TxtClipboardZone),
                    "%s, %s <strong>%s</strong>",
                    Txt_documents_management_area,
@@ -6908,7 +6908,7 @@ static void Brw_WriteCurrentClipboard (void)
          GrpDat.GrpCod = Gbl.FileBrowser.Clipboard.Cod;
          Grp_GetDataOfGroupByCod (&GrpDat);
 	 Crs.CrsCod = GrpDat.CrsCod;
-	 Crs_GetDataOfCourseByCod (&Crs,Crs_GET_BASIC_DATA);
+	 Crs_GetDataOfCourseByCod (&Crs);
          snprintf (TxtClipboardZone,sizeof (TxtClipboardZone),
                    "%s, %s <strong>%s</strong>, %s <strong>%s %s</strong>",
                    Txt_documents_management_area,
@@ -6917,7 +6917,7 @@ static void Brw_WriteCurrentClipboard (void)
          break;
       case Brw_ADMI_TCH_CRS:
 	 Crs.CrsCod = Gbl.FileBrowser.Clipboard.Cod;
-	 Crs_GetDataOfCourseByCod (&Crs,Crs_GET_BASIC_DATA);
+	 Crs_GetDataOfCourseByCod (&Crs);
          snprintf (TxtClipboardZone,sizeof (TxtClipboardZone),
                    "%s, %s <strong>%s</strong>",
                    Txt_teachers_files_area,
@@ -6927,7 +6927,7 @@ static void Brw_WriteCurrentClipboard (void)
          GrpDat.GrpCod = Gbl.FileBrowser.Clipboard.Cod;
          Grp_GetDataOfGroupByCod (&GrpDat);
 	 Crs.CrsCod = GrpDat.CrsCod;
-	 Crs_GetDataOfCourseByCod (&Crs,Crs_GET_BASIC_DATA);
+	 Crs_GetDataOfCourseByCod (&Crs);
          snprintf (TxtClipboardZone,sizeof (TxtClipboardZone),
                    "%s, %s <strong>%s</strong>, %s <strong>%s %s</strong>",
                    Txt_teachers_files_area,
@@ -6936,7 +6936,7 @@ static void Brw_WriteCurrentClipboard (void)
          break;
       case Brw_ADMI_SHR_CRS:
 	 Crs.CrsCod = Gbl.FileBrowser.Clipboard.Cod;
-	 Crs_GetDataOfCourseByCod (&Crs,Crs_GET_BASIC_DATA);
+	 Crs_GetDataOfCourseByCod (&Crs);
          snprintf (TxtClipboardZone,sizeof (TxtClipboardZone),
                    "%s, %s <strong>%s</strong>",
                    Txt_shared_files_area,
@@ -6946,7 +6946,7 @@ static void Brw_WriteCurrentClipboard (void)
          GrpDat.GrpCod = Gbl.FileBrowser.Clipboard.Cod;
          Grp_GetDataOfGroupByCod (&GrpDat);
 	 Crs.CrsCod = GrpDat.CrsCod;
-	 Crs_GetDataOfCourseByCod (&Crs,Crs_GET_BASIC_DATA);
+	 Crs_GetDataOfCourseByCod (&Crs);
          snprintf (TxtClipboardZone,sizeof (TxtClipboardZone),
                    "%s, %s <strong>%s</strong>, %s <strong>%s %s</strong>",
                    Txt_shared_files_area,
@@ -6955,7 +6955,7 @@ static void Brw_WriteCurrentClipboard (void)
          break;
       case Brw_ADMI_ASG_USR:
 	 Crs.CrsCod = Gbl.FileBrowser.Clipboard.Cod;
-	 Crs_GetDataOfCourseByCod (&Crs,Crs_GET_BASIC_DATA);
+	 Crs_GetDataOfCourseByCod (&Crs);
          snprintf (TxtClipboardZone,sizeof (TxtClipboardZone),
                    "%s, %s <strong>%s</strong>, %s <strong>%s</strong>",
                    Txt_assignments_area,
@@ -6964,7 +6964,7 @@ static void Brw_WriteCurrentClipboard (void)
          break;
       case Brw_ADMI_WRK_USR:
 	 Crs.CrsCod = Gbl.FileBrowser.Clipboard.Cod;
-	 Crs_GetDataOfCourseByCod (&Crs,Crs_GET_BASIC_DATA);
+	 Crs_GetDataOfCourseByCod (&Crs);
          snprintf (TxtClipboardZone,sizeof (TxtClipboardZone),
                    "%s, %s <strong>%s</strong>, %s <strong>%s</strong>",
                    Txt_works_area,
@@ -6973,7 +6973,7 @@ static void Brw_WriteCurrentClipboard (void)
          break;
       case Brw_ADMI_ASG_CRS:
 	 Crs.CrsCod = Gbl.FileBrowser.Clipboard.Cod;
-	 Crs_GetDataOfCourseByCod (&Crs,Crs_GET_BASIC_DATA);
+	 Crs_GetDataOfCourseByCod (&Crs);
          Usr_UsrDataConstructor (&UsrDat);
          UsrDat.UsrCod = Gbl.FileBrowser.Clipboard.WorksUsrCod;
          Usr_GetAllUsrDataFromUsrCod (&UsrDat,Usr_DONT_GET_PREFS);
@@ -6986,7 +6986,7 @@ static void Brw_WriteCurrentClipboard (void)
          break;
       case Brw_ADMI_WRK_CRS:
 	 Crs.CrsCod = Gbl.FileBrowser.Clipboard.Cod;
-	 Crs_GetDataOfCourseByCod (&Crs,Crs_GET_BASIC_DATA);
+	 Crs_GetDataOfCourseByCod (&Crs);
          Usr_UsrDataConstructor (&UsrDat);
          UsrDat.UsrCod = Gbl.FileBrowser.Clipboard.WorksUsrCod;
          Usr_GetAllUsrDataFromUsrCod (&UsrDat,Usr_DONT_GET_PREFS);
@@ -7003,7 +7003,7 @@ static void Brw_WriteCurrentClipboard (void)
          Prj.PrjCod = Gbl.FileBrowser.Clipboard.Cod;
          Prj_GetDataOfProjectByCod (&Prj);
 	 Crs.CrsCod = Prj.CrsCod;
-	 Crs_GetDataOfCourseByCod (&Crs,Crs_GET_BASIC_DATA);
+	 Crs_GetDataOfCourseByCod (&Crs);
          snprintf (TxtClipboardZone,sizeof (TxtClipboardZone),
                    "%s, %s <strong>%s</strong>, %s <strong>%s</strong>",
                    Gbl.FileBrowser.Clipboard.FileBrowser == Brw_ADMI_DOC_PRJ ? Txt_project_documents :
@@ -7014,7 +7014,7 @@ static void Brw_WriteCurrentClipboard (void)
          break;
       case Brw_ADMI_MRK_CRS:
 	 Crs.CrsCod = Gbl.FileBrowser.Clipboard.Cod;
-	 Crs_GetDataOfCourseByCod (&Crs,Crs_GET_BASIC_DATA);
+	 Crs_GetDataOfCourseByCod (&Crs);
          snprintf (TxtClipboardZone,sizeof (TxtClipboardZone),
                    "%s, %s <strong>%s</strong>",
                    Txt_marks_management_area,
@@ -7024,7 +7024,7 @@ static void Brw_WriteCurrentClipboard (void)
          GrpDat.GrpCod = Gbl.FileBrowser.Clipboard.Cod;
          Grp_GetDataOfGroupByCod (&GrpDat);
 	 Crs.CrsCod = GrpDat.CrsCod;
-	 Crs_GetDataOfCourseByCod (&Crs,Crs_GET_BASIC_DATA);
+	 Crs_GetDataOfCourseByCod (&Crs);
          snprintf (TxtClipboardZone,sizeof (TxtClipboardZone),
                    "%s, %s <strong>%s</strong>, %s <strong>%s %s</strong>",
                    Txt_marks_management_area,
@@ -7906,7 +7906,7 @@ static void Brw_PasteClipboard (void)
          case Brw_ADMI_SHR_CRS:
          case Brw_ADMI_MRK_CRS:
             Crs.CrsCod = Gbl.FileBrowser.Clipboard.Cod;
-            if (Crs_GetDataOfCourseByCod (&Crs,Crs_GET_BASIC_DATA))
+            if (Crs_GetDataOfCourseByCod (&Crs))
 	       snprintf (PathOrg,sizeof (PathOrg),
 		         "%s/%ld/%s",
                          Cfg_PATH_CRS_PRIVATE,Crs.CrsCod,
@@ -7921,7 +7921,7 @@ static void Brw_PasteClipboard (void)
 	    GrpDat.GrpCod = Gbl.FileBrowser.Clipboard.Cod;
 	    Grp_GetDataOfGroupByCod (&GrpDat);
             Crs.CrsCod = GrpDat.CrsCod;
-            if (Crs_GetDataOfCourseByCod (&Crs,Crs_GET_BASIC_DATA))
+            if (Crs_GetDataOfCourseByCod (&Crs))
 	       snprintf (PathOrg,sizeof (PathOrg),
 		         "%s/%ld/%s/%ld/%s",
                          Cfg_PATH_CRS_PRIVATE,Crs.CrsCod,Cfg_FOLDER_GRP,
@@ -7933,7 +7933,7 @@ static void Brw_PasteClipboard (void)
          case Brw_ADMI_ASG_CRS:
          case Brw_ADMI_WRK_CRS:
             Crs.CrsCod = Gbl.FileBrowser.Clipboard.Cod;
-            if (Crs_GetDataOfCourseByCod (&Crs,Crs_GET_BASIC_DATA))
+            if (Crs_GetDataOfCourseByCod (&Crs))
               {
                Usr_UsrDataConstructor (&UsrDat);
 	       UsrDat.UsrCod = Gbl.FileBrowser.Clipboard.WorksUsrCod;
@@ -7952,7 +7952,7 @@ static void Brw_PasteClipboard (void)
          case Brw_ADMI_ASG_USR:
          case Brw_ADMI_WRK_USR:
             Crs.CrsCod = Gbl.FileBrowser.Clipboard.Cod;
-            if (Crs_GetDataOfCourseByCod (&Crs,Crs_GET_BASIC_DATA))
+            if (Crs_GetDataOfCourseByCod (&Crs))
 	       snprintf (PathOrg,sizeof (PathOrg),
 		         "%s/%ld/%s/%02u/%ld/%s",
                          Cfg_PATH_CRS_PRIVATE,Crs.CrsCod,Cfg_FOLDER_USR,
@@ -7966,7 +7966,7 @@ static void Brw_PasteClipboard (void)
          case Brw_ADMI_ASS_PRJ:
             PrjCod = Gbl.FileBrowser.Clipboard.Cod;
 	    Crs.CrsCod = Prj_GetCourseOfProject (PrjCod);
-	    if (Crs_GetDataOfCourseByCod (&Crs,Crs_GET_BASIC_DATA))
+	    if (Crs_GetDataOfCourseByCod (&Crs))
 	       snprintf (PathOrg,sizeof (PathOrg),
 		         "%s/%ld/%s/%02u/%ld/%s",
 			Cfg_PATH_CRS_PRIVATE,Crs.CrsCod,Cfg_FOLDER_PRJ,
@@ -11076,7 +11076,7 @@ void Brw_GetCrsGrpFromFileMetadata (Brw_FileBrowser_t FileBrowser,long Cod,
 	 /* Cod stores the course code */
 	 *GrpCod = -1L;
 	 *CrsCod = Crs.CrsCod = Cod;
-	 Crs_GetDataOfCourseByCod (&Crs,Crs_GET_BASIC_DATA);
+	 Crs_GetDataOfCourseByCod (&Crs);
 	 *DegCod = Deg.DegCod = Crs.DegCod;
 	 Deg_GetDataOfDegreeByCod (&Deg);
 	 *CtrCod = Ctr.CtrCod = Deg.CtrCod;
@@ -11091,7 +11091,7 @@ void Brw_GetCrsGrpFromFileMetadata (Brw_FileBrowser_t FileBrowser,long Cod,
 	 *GrpCod = GrpDat.GrpCod = Cod;
 	 Grp_GetDataOfGroupByCod (&GrpDat);
 	 *CrsCod = Crs.CrsCod = GrpDat.CrsCod;
-	 Crs_GetDataOfCourseByCod (&Crs,Crs_GET_BASIC_DATA);
+	 Crs_GetDataOfCourseByCod (&Crs);
 	 *DegCod = Deg.DegCod = Crs.DegCod;
 	 Deg_GetDataOfDegreeByCod (&Deg);
 	 *CtrCod = Ctr.CtrCod = Deg.CtrCod;
@@ -11103,7 +11103,7 @@ void Brw_GetCrsGrpFromFileMetadata (Brw_FileBrowser_t FileBrowser,long Cod,
 	 /* Cod stores the project code */
 	 *GrpCod = -1L;
 	 *CrsCod = Crs.CrsCod = Prj_GetCourseOfProject (Cod);
-	 Crs_GetDataOfCourseByCod (&Crs,Crs_GET_BASIC_DATA);
+	 Crs_GetDataOfCourseByCod (&Crs);
 	 *DegCod = Deg.DegCod = Crs.DegCod;
 	 Deg_GetDataOfDegreeByCod (&Deg);
 	 *CtrCod = Ctr.CtrCod = Deg.CtrCod;
@@ -11711,7 +11711,7 @@ void Brw_RemoveUsrWorksInAllCrss (struct UsrData *UsrDat)
 	 row = mysql_fetch_row (mysql_res);
          Crs.CrsCod = Str_ConvertStrCodToLongCod (row[0]);
          /* Get data of course */
-         Crs_GetDataOfCourseByCod (&Crs,Crs_GET_BASIC_DATA);
+         Crs_GetDataOfCourseByCod (&Crs);
          Brw_RemoveUsrWorksInCrs (UsrDat,&Crs);
          NumCrssWorksRemoved++;
 	}

swad_forum.c

@@ -2207,14 +2207,14 @@ void For_SetForumName (struct Forum *Forum,
          break;
       case For_FORUM_COURSE_USRS:
 	 Crs.CrsCod = Forum->Location;
-	 if (!Crs_GetDataOfCourseByCod (&Crs,Crs_GET_BASIC_DATA))
+	 if (!Crs_GetDataOfCourseByCod (&Crs))
 	    Lay_ShowErrorAndExit ("Course not found.");
          Str_Copy (ForumName,Crs.ShrtName,
                    For_MAX_BYTES_FORUM_NAME);
          break;
       case For_FORUM_COURSE_TCHS:
 	 Crs.CrsCod = Forum->Location;
-	 if (!Crs_GetDataOfCourseByCod (&Crs,Crs_GET_BASIC_DATA))
+	 if (!Crs_GetDataOfCourseByCod (&Crs))
 	    Lay_ShowErrorAndExit ("Course not found.");
          snprintf (ForumName,For_MAX_BYTES_FORUM_NAME + 1,
                    "%s%s",Crs.ShrtName,

swad_global.h

@@ -794,10 +794,14 @@ struct Globals
         } NumUsrsWhoClaimToBelongToCtr;
       struct
         {
-	 Rol_Role_t Role;
 	 long CtrCod;
 	 unsigned NumUsrs;
-        } NumUsrsInCrssOfCtr;
+        } NumUsrsInCrssOfCtr[Rol_NUM_ROLES];
+      struct
+        {
+	 long CrsCod;
+	 unsigned NumUsrs;
+        } NumUsrsInCrs[Rol_NUM_ROLES];
       struct
 	{
 	 long UsrCod;

swad_help.c

@@ -161,17 +161,17 @@ void Hlp_ShowHelpWhatWouldYouLikeToDo (void)
 
       if (Gbl.Usrs.Me.MyCrss.Num)	// I am enroled in some courses
 	{
-	 if (Gbl.Hierarchy.Level == Hie_CRS &&			// Course selected
+	 if (Gbl.Hierarchy.Level == Hie_CRS &&				// Course selected
-	     !Gbl.Hierarchy.Crs.NumUsrs[Rol_STD] &&		// Current course has no students
 	     Gbl.Usrs.Me.UsrDat.Roles.InCurrentCrs.Role == Rol_TCH)	// I am a teacher in current course
-	   {
+	    if (!Usr_GetNumUsrsInCrs (Rol_STD,Gbl.Hierarchy.Crs.CrsCod))// Current course has no students
-	    /* Request students enrolment */
+	      {
-	    Hlp_ShowRowHelpWhatWouldYouLikeToDo (Str_BuildStringStr (Txt_Register_students_in_COURSE_X,
+	       /* Request students enrolment */
-								     Gbl.Hierarchy.Crs.ShrtName),
+	       Hlp_ShowRowHelpWhatWouldYouLikeToDo (Str_BuildStringStr (Txt_Register_students_in_COURSE_X,
-						 ActReqEnrSevStd,
+									Gbl.Hierarchy.Crs.ShrtName),
-						 Btn_CREATE_BUTTON,Txt_Register_students);
+						    ActReqEnrSevStd,
-	    Str_FreeString ();
+						    Btn_CREATE_BUTTON,Txt_Register_students);
-	   }
+	       Str_FreeString ();
+	      }
 
 	 if (Gbl.Action.Act != ActMyCrs)	// I am not seeing the action to list my courses
 	    /* Request list my courses */

swad_hierarchy.c

@@ -525,8 +525,7 @@ void Hie_InitHierarchy (void)
    /***** If course code is available, get course data *****/
    if (Gbl.Hierarchy.Crs.CrsCod > 0)
      {
-      if (Crs_GetDataOfCourseByCod (&Gbl.Hierarchy.Crs,		// Course found
+      if (Crs_GetDataOfCourseByCod (&Gbl.Hierarchy.Crs))	// Course found
-				    Crs_GET_EXTRA_DATA))	// Get extra data because they may be needed later
          Gbl.Hierarchy.Deg.DegCod = Gbl.Hierarchy.Crs.DegCod;
       else
          Hie_ResetHierarchy ();

swad_layout.c

@@ -1561,7 +1561,7 @@ void Lay_WriteHeaderClassPhoto (bool PrintView,bool DrawingClassPhoto,
 
    /***** Get data of course *****/
    Crs.CrsCod = CrsCod;
-   Crs_GetDataOfCourseByCod (&Crs,Crs_GET_BASIC_DATA);
+   Crs_GetDataOfCourseByCod (&Crs);
 
    /***** Begin table *****/
    HTM_TABLE_BeginWidePadding (10);

swad_mark.c

@@ -623,8 +623,7 @@ void Mrk_ShowMyMarks (void)
         }
       else					// Course zone
         {
-	 // if (Usr_GetNumUsrsInCrs (Rol_STD,Gbl.Hierarchy.Crs.CrsCod))	// If there are students in this course
+	 if (Usr_GetNumUsrsInCrs (Rol_STD,Gbl.Hierarchy.Crs.CrsCod))	// If there are students in this course
-         if (Gbl.Hierarchy.Crs.NumUsrs[Rol_STD])
            {
             Gbl.Usrs.Other.UsrDat.UsrCod = Usr_GetRamdomStdFromCrs (Gbl.Hierarchy.Crs.CrsCod);
             UsrDat = &Gbl.Usrs.Other.UsrDat;

swad_message.c

@@ -1030,7 +1030,7 @@ void Msg_GetParamMsgsCrsCod (void)
      {
       /* Get data of course */
       Crs.CrsCod = Gbl.Msg.FilterCrsCod;
-      Crs_GetDataOfCourseByCod (&Crs,Crs_GET_BASIC_DATA);
+      Crs_GetDataOfCourseByCod (&Crs);
 
       Str_Copy (Gbl.Msg.FilterCrsShrtName,Crs.ShrtName,
                 Hie_MAX_BYTES_SHRT_NAME);
@@ -2597,7 +2597,7 @@ void Msg_GetDistinctCoursesInMyMessages (void)
       row = mysql_fetch_row (mysql_res);
       Crs.CrsCod = Str_ConvertStrCodToLongCod (row[0]);
       if (Crs.CrsCod >= 0 && Gbl.Msg.NumCourses < Crs_MAX_COURSES_PER_USR)
-         if (Crs_GetDataOfCourseByCod (&Crs,Crs_GET_BASIC_DATA))
+         if (Crs_GetDataOfCourseByCod (&Crs))
            {
             Gbl.Msg.Courses[Gbl.Msg.NumCourses].CrsCod = Crs.CrsCod;
             Str_Copy (Gbl.Msg.Courses[Gbl.Msg.NumCourses].ShrtName,Crs.ShrtName,
@@ -3279,7 +3279,7 @@ bool Msg_WriteCrsOrgMsg (long CrsCod)
       Crs.CrsCod = CrsCod;
 
       /* Get data of current degree */
-      if (Crs_GetDataOfCourseByCod (&Crs,Crs_GET_BASIC_DATA))
+      if (Crs_GetDataOfCourseByCod (&Crs))
         {
          ThereIsOrgCrs = true;
          if ((FromThisCrs = (CrsCod == Gbl.Hierarchy.Crs.CrsCod)))	// Message sent from current course

swad_notification.c

@@ -415,7 +415,7 @@ void Ntf_ShowMyNotifications (void)
 
          /* Get course code (row[5]) */
          Crs.CrsCod = Str_ConvertStrCodToLongCod (row[5]);
-         Crs_GetDataOfCourseByCod (&Crs,Crs_GET_BASIC_DATA);
+         Crs_GetDataOfCourseByCod (&Crs);
 
          /* Get message/post/... code (row[6]) */
          Cod = Str_ConvertStrCodToLongCod (row[6]);
@@ -1244,7 +1244,7 @@ unsigned Ntf_StoreNotifyEventsToAllUsrs (Ntf_NotifyEvent_t NotifyEvent,long Cod)
       case Ntf_EVENT_ENROLMENT_TCH:	// This function should not be called in this case
          return 0;
       case Ntf_EVENT_ENROLMENT_REQUEST:
-	 if (Gbl.Hierarchy.Crs.NumUsrs[Rol_TCH])
+	 if (Usr_GetNumUsrsInCrs (Rol_TCH,Gbl.Hierarchy.Crs.CrsCod))
 	   {
 	    // If this course has teachers ==> send notification to teachers
 	    NumRows = DB_QuerySELECT (&mysql_res,"can not get users"
@@ -1662,7 +1662,7 @@ static void Ntf_SendPendingNotifByEMailToOneUsr (struct UsrData *ToUsrDat,unsign
 
 	    /* Get course code (row[5]) */
 	    Crs.CrsCod = Str_ConvertStrCodToLongCod (row[5]);
-	    Crs_GetDataOfCourseByCod (&Crs,Crs_GET_BASIC_DATA);
+	    Crs_GetDataOfCourseByCod (&Crs);
 
 	    /* Get message/post/... code (row[6]) */
 	    Cod = Str_ConvertStrCodToLongCod (row[6]);

swad_report.c

@@ -1161,7 +1161,7 @@ static void Rep_WriteRowCrsData (long CrsCod,Rol_Role_t Role,
 
    /***** Get course data *****/
    Crs.CrsCod = CrsCod;
-   Crs_GetDataOfCourseByCod (&Crs,Crs_GET_EXTRA_DATA);
+   Crs_GetDataOfCourseByCod (&Crs);
 
    /***** Get degree data *****/
    Deg.DegCod = Crs.DegCod;

swad_statistic.c

@@ -3619,7 +3619,7 @@ static void Sta_ShowNumHitsPerCourse (unsigned long NumRows,
       Crs.CrsCod = Str_ConvertStrCodToLongCod (row[0]);
 
       /* Get data of current degree */
-      CrsOK = Crs_GetDataOfCourseByCod (&Crs,Crs_GET_BASIC_DATA);
+      CrsOK = Crs_GetDataOfCourseByCod (&Crs);
 
       HTM_TR_Begin (NULL);
 

swad_timeline.c

@@ -1631,7 +1631,7 @@ static void TL_WriteNote (const struct TL_Note *SocNot,
 	       case TL_NOTE_NOTICE:
 		  /* Get course data */
 		  Crs.CrsCod = SocNot->HieCod;
-		  Crs_GetDataOfCourseByCod (&Crs,Crs_GET_BASIC_DATA);
+		  Crs_GetDataOfCourseByCod (&Crs);
 		  break;
 	       case TL_NOTE_FORUM_POST:
 		  /* Get forum type of the post */

swad_timetable.c

@@ -1547,7 +1547,7 @@ static void TT_TimeTableDrawCell (unsigned Weekday,unsigned Interval,unsigned Co
 	    if (Gbl.TimeTable.Type == TT_MY_TIMETABLE)
               {
                Crs.CrsCod = CrsCod;
-               Crs_GetDataOfCourseByCod (&Crs,Crs_GET_BASIC_DATA);
+               Crs_GetDataOfCourseByCod (&Crs);
                if (ClassType == TT_LECTURE ||
                    ClassType == TT_PRACTICAL)
         	 {

swad_user.c

@@ -4167,14 +4167,56 @@ static void Usr_WriteUsrData (const char *BgColor,
 /************* Get number of users with a role in a course *******************/
 /*****************************************************************************/
 
+void Usr_FlushCacheNumUsrsInCrs (void)
+  {
+   Gbl.Cache.NumUsrsInCrs[Rol_UNK].CrsCod =
+   Gbl.Cache.NumUsrsInCrs[Rol_STD].CrsCod =
+   Gbl.Cache.NumUsrsInCrs[Rol_NET].CrsCod =
+   Gbl.Cache.NumUsrsInCrs[Rol_TCH].CrsCod = -1L;
+
+   Gbl.Cache.NumUsrsInCrs[Rol_UNK].NumUsrs =
+   Gbl.Cache.NumUsrsInCrs[Rol_STD].NumUsrs =
+   Gbl.Cache.NumUsrsInCrs[Rol_NET].NumUsrs =
+   Gbl.Cache.NumUsrsInCrs[Rol_TCH].NumUsrs = 0;
+  }
+
 unsigned Usr_GetNumUsrsInCrs (Rol_Role_t Role,long CrsCod)
   {
-   /***** Get the number of teachers in a course from database ******/
+   /***** 1. Fast check: Trivial case *****/
-   return
+   if (CrsCod <= 0)
-   (unsigned) DB_QueryCOUNT ("can not get the number of users in a course",
+      return 0;
-			     "SELECT COUNT(*) FROM crs_usr"
+
-			     " WHERE CrsCod=%ld AND Role=%u",
+   /***** 2. Fast check: Trivial case *****/
-			     CrsCod,(unsigned) Role);
+   switch (Role)
+     {
+      case Rol_UNK:	// Here Rol_UNK means all
+      case Rol_STD:
+      case Rol_NET:
+      case Rol_TCH:
+	 break;
+      default:
+	 return 0;
+     }
+
+   /***** 3. Fast check: If cached... *****/
+   if (CrsCod == Gbl.Cache.NumUsrsInCrs[Role].CrsCod)
+      return Gbl.Cache.NumUsrsInCrs[Role].NumUsrs;
+
+   /***** 4. Slow: number of users in a course from database *****/
+   Gbl.Cache.NumUsrsInCrs[Role].CrsCod = CrsCod;
+   if (Role == Rol_UNK)
+      Gbl.Cache.NumUsrsInCrs[Rol_UNK].NumUsrs =
+      (unsigned) DB_QueryCOUNT ("can not get the number of users in a course",
+				"SELECT COUNT(*) FROM crs_usr"
+				" WHERE CrsCod=%ld",
+				CrsCod);
+   else
+      Gbl.Cache.NumUsrsInCrs[Role].NumUsrs =
+      (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);
+   return Gbl.Cache.NumUsrsInCrs[Role].NumUsrs;
   }
 
 /*****************************************************************************/
@@ -4202,9 +4244,15 @@ unsigned Usr_GetNumUsrsInCrssOfDeg (Rol_Role_t Role,long DegCod)
 
 void Usr_FlushCacheNumUsrsInCrssOfCtr (void)
   {
-   Gbl.Cache.NumUsrsInCrssOfCtr.Role    = Rol_UNK;
+   Gbl.Cache.NumUsrsInCrssOfCtr[Rol_UNK].CtrCod =
-   Gbl.Cache.NumUsrsInCrssOfCtr.CtrCod  = -1L;
+   Gbl.Cache.NumUsrsInCrssOfCtr[Rol_STD].CtrCod =
-   Gbl.Cache.NumUsrsInCrssOfCtr.NumUsrs = 0;
+   Gbl.Cache.NumUsrsInCrssOfCtr[Rol_NET].CtrCod =
+   Gbl.Cache.NumUsrsInCrssOfCtr[Rol_TCH].CtrCod = -1L;
+
+   Gbl.Cache.NumUsrsInCrssOfCtr[Rol_UNK].NumUsrs =
+   Gbl.Cache.NumUsrsInCrssOfCtr[Rol_STD].NumUsrs =
+   Gbl.Cache.NumUsrsInCrssOfCtr[Rol_NET].NumUsrs =
+   Gbl.Cache.NumUsrsInCrssOfCtr[Rol_TCH].NumUsrs = 0;
   }
 
 unsigned Usr_GetNumUsrsInCrssOfCtr (Rol_Role_t Role,long CtrCod)
@@ -4213,17 +4261,27 @@ unsigned Usr_GetNumUsrsInCrssOfCtr (Rol_Role_t Role,long CtrCod)
    if (CtrCod <= 0)
       return 0;
 
-   /***** 2. Fast check: If cached... *****/
+   /***** 2. Fast check: Trivial case *****/
-   if (Role == Gbl.Cache.NumUsrsInCrssOfCtr.Role &&
+   switch (Role)
-       CtrCod == Gbl.Cache.NumUsrsInCrssOfCtr.CtrCod)
+     {
-      return Gbl.Cache.NumUsrsInCrssOfCtr.NumUsrs;
+      case Rol_UNK:	// Here Rol_UNK means all
+      case Rol_STD:
+      case Rol_NET:
+      case Rol_TCH:
+	 break;
+      default:
+	 return 0;
+     }
 
-   /***** 3. Slow: get number of users in courses of a centre
+   /***** 3. Fast check: If cached... *****/
+   if (CtrCod == Gbl.Cache.NumUsrsInCrssOfCtr[Role].CtrCod)
+      return Gbl.Cache.NumUsrsInCrssOfCtr[Role].NumUsrs;
+
+   /***** 4. Slow: get number of users in courses of a centre
                    from database *****/
-   Gbl.Cache.NumUsrsInCrssOfCtr.Role   = Role;
+   Gbl.Cache.NumUsrsInCrssOfCtr[Role].CtrCod = CtrCod;
-   Gbl.Cache.NumUsrsInCrssOfCtr.CtrCod = CtrCod;
    if (Role == Rol_UNK)	// Any user
-      Gbl.Cache.NumUsrsInCrssOfCtr.NumUsrs =
+      Gbl.Cache.NumUsrsInCrssOfCtr[Rol_UNK].NumUsrs =
       (unsigned) DB_QueryCOUNT ("can not get the number of users"
 				" in courses of a centre",
 				"SELECT COUNT(DISTINCT crs_usr.UsrCod)"
@@ -4235,7 +4293,7 @@ unsigned Usr_GetNumUsrsInCrssOfCtr (Rol_Role_t Role,long 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
-      Gbl.Cache.NumUsrsInCrssOfCtr.NumUsrs =
+      Gbl.Cache.NumUsrsInCrssOfCtr[Role].NumUsrs =
       (unsigned) DB_QueryCOUNT ("can not get the number of users"
 				" in courses of a centre",
 				"SELECT COUNT(DISTINCT crs_usr.UsrCod)"
@@ -4245,7 +4303,7 @@ unsigned Usr_GetNumUsrsInCrssOfCtr (Rol_Role_t Role,long CtrCod)
 				" AND courses.CrsCod=crs_usr.CrsCod"
 				" AND crs_usr.Role=%u",
 				CtrCod,(unsigned) Role);
-   return Gbl.Cache.NumUsrsInCrssOfCtr.NumUsrs;
+   return Gbl.Cache.NumUsrsInCrssOfCtr[Role].NumUsrs;
   }
 
 /*****************************************************************************/
@@ -9804,21 +9862,7 @@ double Usr_GetNumUsrsPerCrs (Rol_Role_t Role)
 			    (unsigned) Role);
          break;
       case Hie_CRS:
-	 switch (Role)
+	 return (double) Usr_GetNumUsrsInCrs (Role,Gbl.Hierarchy.Crs.CrsCod);
-	   {
-	    case Rol_UNK:
-	       return (double) Gbl.Hierarchy.Crs.NumUsrs[Rol_UNK];	// Any user
-	    case Rol_STD:
-	       return (double) Gbl.Hierarchy.Crs.NumUsrs[Rol_STD];	// Students
-	    case Rol_NET:
-	       return (double) Gbl.Hierarchy.Crs.NumUsrs[Rol_UNK];	// Non-editing teachers
-	    case Rol_TCH:
-	       return (double) Gbl.Hierarchy.Crs.NumUsrs[Rol_UNK];	// Teachers
-	    default:
-	       Rol_WrongRoleExit ();
-	       break;	// Not reached
-	   }
-	 break;
       default:
          Lay_WrongScopeExit ();
          break;

swad_user.h

@@ -407,6 +407,7 @@ void Usr_WriteRowUsrMainData (unsigned NumUsr,struct UsrData *UsrDat,
                               bool PutCheckBoxToSelectUsr,Rol_Role_t Role,
 			      struct SelectedUsrs *SelectedUsrs);
 
+void Usr_FlushCacheNumUsrsInCrs (void);
 unsigned Usr_GetNumUsrsInCrs (Rol_Role_t Role,long CrsCod);
 unsigned Usr_GetNumUsrsInCrssOfDeg (Rol_Role_t Role,long DegCod);
 void Usr_FlushCacheNumUsrsInCrssOfCtr (void);