Use transactions when simulating queries (#312)

Author: xPaw

src/QueryReflection/MysqliQueryReflector.php

@@ -131,6 +131,8 @@ private function simulateQuery(string $queryString)
             return $this->cache[$queryString] = null;
         }
 
+        $this->db->begin_transaction(\MYSQLI_TRANS_START_READ_ONLY);
+
         try {
             $result = $this->db->query($simulatedQuery);
 
@@ -144,6 +146,8 @@ private function simulateQuery(string $queryString)
             return $this->cache[$queryString] = $resultInfo;
         } catch (mysqli_sql_exception $e) {
             return $this->cache[$queryString] = $e;
+        } finally {
+            $this->db->rollback();
         }
     }
 }

src/QueryReflection/PdoQueryReflector.php

@@ -139,10 +139,22 @@ private function simulateQuery(string $queryString)
             return $this->cache[$queryString] = null;
         }
 
+        try {
+            $this->pdo->beginTransaction();
+        } catch (PDOException $e) {
+            // not all drivers may support transactions
+        }
+
         try {
             $stmt = $this->pdo->query($simulatedQuery);
         } catch (PDOException $e) {
             return $this->cache[$queryString] = $e;
+        } finally {
+            try {
+                $this->pdo->rollBack();
+            } catch (PDOException $e) {
+                // not all drivers may support transactions
+            }
         }
 
         $this->cache[$queryString] = [];