[HttpFoundation] Fix defining expiry index in PdoSessionHandler::configureSchema()

Author: nicolas-grekas

Session/Storage/Handler/PdoSessionHandler.php

@@ -225,6 +225,7 @@ public function configureSchema(Schema $schema, \Closure $isSameDatabase = null)
                 throw new \DomainException(sprintf('Creating the session table is currently not implemented for PDO driver "%s".', $this->driver));
         }
         $table->setPrimaryKey([$this->idCol]);
+        $table->addIndex([$this->lifetimeCol], $this->lifetimeCol.'_idx');
     }
 
     /**
@@ -259,7 +260,7 @@ public function createTable()
 
         try {
             $this->pdo->exec($sql);
-            $this->pdo->exec("CREATE INDEX expiry ON $this->table ($this->lifetimeCol)");
+            $this->pdo->exec("CREATE INDEX {$this->lifetimeCol}_idx ON $this->table ($this->lifetimeCol)");
         } catch (\PDOException $e) {
             $this->rollback();