From 60eaa9bcb096b65bab115106c1f2f19c867225e4 Mon Sep 17 00:00:00 2001
From: Peter <peterrolanddias@gmail.com>
Date: Wed, 22 May 2019 18:51:49 +0800
Subject: [PATCH] MDL-55997 core_reports: modify user stats query to fix
 duplicate rows

---
 lib/statslib.php      |  4 +++-
 report/stats/user.php | 31 +++++++++++++++++++++++++------
 2 files changed, 28 insertions(+), 7 deletions(-)

diff --git a/lib/statslib.php b/lib/statslib.php
index a8970faa62e9..f449f07f5607 100644
--- a/lib/statslib.php
+++ b/lib/statslib.php
@@ -1196,11 +1196,13 @@ function stats_get_parameters($time,$report,$courseid,$mode,$roleid=0) {
         break;
 
     case STATS_REPORT_USER_VIEW:
-        $param->fields = 'statsreads as line1, statswrites as line2, statsreads+statswrites as line3';
+        $param->fields = 'timeend, SUM(statsreads) AS line1, SUM(statswrites) AS line2, SUM(statsreads+statswrites) AS line3';
+        $param->fieldscomplete = true;
         $param->line1 = get_string('statsuserreads');
         $param->line2 = get_string('statsuserwrites');
         $param->line3 = get_string('statsuseractivity');
         $param->stattype = 'activity';
+        $param->extras = "GROUP BY timeend";
         break;
 
     // ******************** STATS_MODE_RANKED ******************** //
diff --git a/report/stats/user.php b/report/stats/user.php
index 547714234f02..ae71c4f8c202 100644
--- a/report/stats/user.php
+++ b/report/stats/user.php
@@ -124,14 +124,33 @@
 
 $param = stats_get_parameters($time,STATS_REPORT_USER_VIEW,$course->id,STATS_MODE_DETAILED);
 $params = $param->params;
-
 $param->table = 'user_'.$param->table;
 
-$sql = 'SELECT id, timeend,'.$param->fields.' FROM {stats_'.$param->table.'} WHERE '
-.(($course->id == SITEID) ? '' : ' courseid = '.$course->id.' AND ')
-    .' userid = '.$user->id.' AND timeend >= '.$param->timeafter .$param->extras
-    .' ORDER BY timeend DESC';
-$stats = $DB->get_records_sql($sql, $params); //TODO: improve these params!!
+// Build the conditions and parameters.
+$wheres = [
+    "userid = :userid",
+    "timeend >= :timeend",
+];
+$params['userid'] = $user->id;
+$params['timeend'] = $param->timeafter;
+// Add condition for course ID when specified.
+if ($course->id != SITEID) {
+    $wheres[] = "courseid = :courseid";
+    $params['courseid'] = $course->id;
+}
+// Combine the conditions.
+$wheresql = implode(" AND ", $wheres);
+
+// Build the query.
+$sql = "
+    SELECT {$param->fields}
+      FROM {stats_{$param->table}}
+     WHERE {$wheresql}
+    {$param->extras}
+  ORDER BY timeend DESC";
+
+// Fetch the stats data.
+$stats = $DB->get_records_sql($sql, $params);
 
 if (empty($stats)) {
     print_error('nostatstodisplay', '', $CFG->wwwroot.'/course/user.php?id='.$course->id.'&user='.$user->id.'&mode=outline');