Add support for index / query hints in query builder

framework/db/Query.php

@@ -74,6 +74,12 @@
      * @see from()
      */
     public $from;
+    /**
+     * @var string|null force to use specific index. For example, `'userTimeCreated'`.
+     * This is used to construct the FROM clause in a SQL statement.
+     * @see forceIndex()
+     */
+    public $forceIndex;
     /**
      * @var array|null how to group the query results. For example, `['company', 'department']`.
      * This is used to construct the GROUP BY clause in a SQL statement.
@@ -825,6 +831,25 @@
         return $this;
     }
 
+    /**
+     * Sets the FORCE INDEX part of the query.
+     * @param string $forceIndex
+     *
+     * Here are some examples:
+     *
+     * ```php
+     * // SELECT * FROM  `user` FORCE INDEX (userTimeCreated);
+     * $query = (new \yii\db\Query)->from('user')->forceIndex('userTimeCreated');
+     * ```
+     *
+     * @return $this the query object itself
+     */
+    public function forceIndex($forceIndex)
+    {
+        $this->forceIndex = $forceIndex;
+        return $this;
+    }
+
     /**
      * Sets the WHERE part of the query.
      *
@@ -1381,6 +1406,7 @@
             'selectOption' => $from->selectOption,
             'distinct' => $from->distinct,
             'from' => $from->from,
+            'forceIndex' => $from->forceIndex,
             'groupBy' => $from->groupBy,
             'join' => $from->join,
             'having' => $from->having,

framework/db/QueryBuilder.php

@@ -230,7 +230,7 @@
 
         $clauses = [
             $this->buildSelect($query->select, $params, $query->distinct, $query->selectOption),
-            $this->buildFrom($query->from, $params),
+            $this->buildFrom($query->from, $params, $query->forceIndex),
             $this->buildJoin($query->join, $params),
             $this->buildWhere($query->where, $params),
             $this->buildGroupBy($query->groupBy),
@@ -1272,17 +1272,24 @@
     /**
      * @param array $tables
      * @param array $params the binding parameters to be populated
+     * @param string $forceIndex
      * @return string the FROM clause built from [[Query::$from]].
      */
-    public function buildFrom($tables, &$params)
+    public function buildFrom($tables, &$params, $forceIndex = null)
     {
         if (empty($tables)) {
             return '';
         }
 
         $tables = $this->quoteTableNames($tables, $params);
 
-        return 'FROM ' . implode(', ', $tables);
+        $from = 'FROM ' . implode(', ', $tables);
+
+        if (!empty($forceIndex)) {
+            $from .= " FORCE INDEX ({$forceIndex}) ";
+        }
+
+        return $from;
     }
 
     /**