[instruments] Bulk load SessionID and VisitLabel (#8855)

When calling bulkLoadInstanceData, currently only instrument data is
bulk loaded from the database. However, calling getSessionID or getVisitLabel
is almost always required in order to use the data. This bulk loads the
session id and visit label from the same query when calling bulkLoadInstanceData.

php/libraries/NDB_BVL_Instrument.class.inc

@@ -1409,37 +1409,44 @@ abstract class NDB_BVL_Instrument extends NDB_Page
         return $allValues[$fieldName];
     }
 
+    private ?SessionID $sessionID;
     /**
      * Gets the sessionID for the timepoint to which this instrument pertains
      *
      * @return ?SessionID The sessionID
      */
     function getSessionID(): ?SessionID
     {
-
-        $query  = "SELECT SessionID FROM flag WHERE CommentID = :CID";
-        $result = \NDB_Factory::singleton()->database()->pselectOne(
-            $query,
-            [
-                'CID' => $this->getCommentID(),
-            ]
-        );
-
-        if (empty($result)) {
-            return null;
+        if (empty($this->sessionID)) {
+            $query  = "SELECT SessionID FROM flag WHERE CommentID = :CID";
+            $result = \NDB_Factory::singleton()->database()->pselectOne(
+                $query,
+                [
+                    'CID' => $this->getCommentID(),
+                ]
+            );
+            if (empty($result)) {
+                return null;
+            }
+            $this->sessionID = new SessionID($result);
         }
-
-        return (new SessionID($result));
+        return $this->sessionID;
     }
 
+    private ?string $visitLabel = null;
     /**
      * Gets the VisitLabel for the timepoint for this instrument.
      *
      * @return string The visit label
      */
     function getVisitLabel(): string
     {
-        return \TimePoint::singleton($this->getSessionID())->getVisitLabel();
+        if ($this->visitLabel === null) {
+            $this->visitLabel = \TimePoint::singleton(
+                $this->getSessionID()
+            )->getVisitLabel();
+        }
+        return $this->visitLabel;
     }
 
     /**
@@ -2211,7 +2218,13 @@ abstract class NDB_BVL_Instrument extends NDB_Page
 
         if ($this->jsonData) {
             $jsondata = $db->pselect(
-                "SELECT CommentID, Data FROM flag WHERE CommentID IN ("
+                "SELECT SessionID,
+                        CommentID,
+                        session.Visit_Label as VisitLabel,
+                        Data
+                    FROM flag
+                        JOIN session ON (session.ID=flag.SessionID)
+                    WHERE CommentID IN ("
                 . join(',', $prepBindings) . ')',
                 $prepValues,
             );
@@ -2220,8 +2233,10 @@ abstract class NDB_BVL_Instrument extends NDB_Page
                     $newinst = clone $this;
 
                     $newinst->commentID    = $row['CommentID'];
+                    $newinst->visitLabel   = $row['VisitLabel'];
+                    $newinst->sessionID    = new SessionID($row['SessionID']);
                     $newinst->instanceData = json_decode(
-                        $row['Data'],
+                        $row['Data'] ?? '{}',
                         true,
                     ) ?? $this->defaultInstanceData();
 
@@ -2231,15 +2246,25 @@ abstract class NDB_BVL_Instrument extends NDB_Page
             );
         } else {
             $defaults = $db->pselect(
-                "SELECT * FROM $this->table WHERE CommentID IN ("
+                "SELECT flag.CommentID as CommentID,
+                        session.Visit_Label as VisitLabel,
+                        session.ID as SessionID, t.*
+                 FROM $this->table t
+                    JOIN flag ON (t.CommentID=flag.CommentID)
+                    JOIN session ON (flag.SessionID=session.ID)
+                 WHERE t.CommentID IN ("
                 . join(',', $prepBindings) . ')',
                 $prepValues,
             );
             return array_map(
                 function ($row) {
                     $newinst = clone $this;
 
-                    $newinst->commentID    = $row['CommentID'];
+                    $newinst->commentID  = $row['CommentID'];
+                    $newinst->visitLabel = $row['VisitLabel'];
+                    $newinst->sessionID  = new SessionID($row['SessionID']);
+                    unset($row['CommentID'], $row['VisitLabel'], $row['SessionID']);
+
                     $newinst->instanceData = $row;
 
                     return $newinst;