NEW Add sortByField and remove mysql specific code from DataList (#11588

)

Co-authored-by: Lenny Obez <github@lennyobez.com>

src/ORM/Connect/Database.php

@@ -954,4 +954,26 @@ abstract public function now();
      * @return string Expression for a random value
      */
     abstract public function random();
+
+    /**
+     * Generate SQL for sorting by a specific field using CASE logic.
+     *
+     * Subclasses can override this method to provide optimized implementations
+     * (e.g., using MySQL's FIELD method).
+     *
+     * @param string $field The name of the field to sort by.
+     * @param array $values The values to order by.
+     * @return string SQL snippet for ordering.
+     */
+    public function sortByField(string $field, array $values): string
+    {
+        $caseStatements = [];
+        foreach ($values as $index => $value) {
+            $escaped = is_int($value) ? $value : "'" . addslashes($value) . "'";
+            $caseStatements[] = "CASE {$field} = {$escaped} THEN {$index}";
+        }
+        $count = count($caseStatements);
+        $sqlCase = implode(' ', $caseStatements);
+        return "CASE {$sqlCase} ELSE {$count} END";
+    }
 }

src/ORM/Connect/MySQLDatabase.php

@@ -586,4 +586,22 @@ public function clearTable($table)
             $this->query("ALTER TABLE \"$table\" AUTO_INCREMENT = 1");
         }
     }
+
+    /**
+     * Generate SQL for sorting by a specific field using MySQL's FIELD function.
+     *
+     * @param string $field The name of the field to sort by.
+     * @param array $values The values to order by.
+     * @return string SQL snippet for ordering.
+     */
+    public function sortByField(string $field, array $values): string
+    {
+        $escapedValues = [];
+        foreach ($values as $value) {
+            $escaped = is_int($value) ? $value : "'" . addslashes($value) . "'";
+            $escapedValues[] = $escaped;
+        }
+        $sqlIds = implode(',', $escapedValues);
+        return "FIELD({$field}, {$sqlIds})";
+    }
 }

src/ORM/DataList.php

@@ -1374,16 +1374,20 @@ private function fetchEagerLoadManyMany(
         // Note that $joinRows also holds extra fields data
         $joinRows = [];
         if (!empty($parentIDs) && !empty($fetchedIDs)) {
-            $fetchedIDsAsString = implode(',', $fetchedIDs);
-            $joinRows = DB::query(
-                'SELECT * FROM "' . $joinTable
+            // Use sortByField to generate the ORDER BY clause
+            $orderByClause = DB::get_conn()->sortByField($childIDField, $fetchedIDs);
+
+            // Build the query with the order clause
+            $joinQuery = 'SELECT * FROM "' . $joinTable
                 // Only get joins relevant for the parent list
                 . '" WHERE "' . $parentIDField . '" IN (' . implode(',', $parentIDs) . ')'
                 // Exclude any children that got filtered out
-                . ' AND ' . $childIDField . ' IN (' . $fetchedIDsAsString . ')'
+                . ' AND ' . $childIDField . ' IN (' . implode(',', $fetchedIDs) . ')'
                 // Respect sort order of fetched items
-                . ' ORDER BY FIELD(' . $childIDField . ', ' . $fetchedIDsAsString . ')'
-            );
+                . ' ORDER BY ' . $orderByClause;
+
+            // Execute the query
+            $joinRows = DB::query($joinQuery);
         }
 
         // Store the children in an EagerLoadedList against the correct parent

tests/php/ORM/DatabaseTest.php

@@ -494,4 +494,63 @@ public function testRewindWithPredicates()
             $i++;
         }
     }
+
+    /**
+     * Test that the sortByField method correctly generates an ORDER BY clause
+     * and the query returns results in the expected order.
+     */
+    public function testSortByFieldIntegration()
+    {
+        // Define test data
+        $parentIDs = [1, 2];
+        $fetchedIDs = [3, 2, 1]; // Expected order
+        $expectedOrder = [3, 2, 1];
+
+        $joinTable = 'TestJoinTable';
+        $parentIDField = 'ParentID';
+        $childIDField = 'ChildID';
+
+        // Create a temporary test table
+        DB::query("
+            CREATE TEMPORARY TABLE {$joinTable} (
+                {$childIDField} INT NOT NULL,
+                {$parentIDField} INT NOT NULL
+            )
+        ");
+
+        // Insert mock data
+        DB::query("
+            INSERT INTO {$joinTable} ({$childIDField}, {$parentIDField})
+            VALUES (1, 1), (2, 2), (3, 1)
+        ");
+
+        // Use sortByField to generate the ORDER BY clause
+        $orderByClause = DB::get_conn()->sortByField($childIDField, $fetchedIDs);
+
+        // Build the query with sortByField
+        $query = "
+            SELECT *
+            FROM {$joinTable}
+            WHERE {$parentIDField} IN (" . implode(',', $parentIDs) . ")
+              AND {$childIDField} IN (" . implode(',', $fetchedIDs) . ")
+            ORDER BY {$orderByClause}
+        ";
+
+        // Execute the query and convert results to an array
+        $result = DB::query($query);
+        $rows = [];
+        foreach ($result as $row) {
+            $rows[] = $row;
+        }
+
+        // Extract the actual order of fetched ChildIDs
+        $actualOrder = array_column($rows, $childIDField);
+
+        // Assert that the results are ordered as expected
+        $this->assertEquals(
+            $expectedOrder,
+            $actualOrder,
+            'The results should maintain the custom order defined by fetchedIDs'
+        );
+    }
 }