[5.2] Enable or disable Foreign Key Constraints

src/Illuminate/Database/Schema/Builder.php

@@ -194,6 +194,30 @@ public function rename($from, $to)
         $this->build($blueprint);
     }
 
+    /**
+     * Enable foreign key constraints.
+     *
+     * @return bool
+     */
+    public function enableForeignKeyConstraints()
+    {
+        return $this->connection->statement(
+            $this->grammar->compileEnableForeignKeyConstraints()
+        );
+    }
+
+    /**
+     * Disable foreign key constraints.
+     *
+     * @return bool
+     */
+    public function disableForeignKeyConstraints()
+    {
+        return $this->connection->statement(
+            $this->grammar->compileDisableForeignKeyConstraints()
+        );
+    }
+
     /**
      * Execute the blueprint to build / modify the table.
      *

src/Illuminate/Database/Schema/Grammars/MySqlGrammar.php

@@ -284,6 +284,26 @@ public function compileRename(Blueprint $blueprint, Fluent $command)
         return "rename table {$from} to ".$this->wrapTable($command->to);
     }
 
+    /**
+     * Compile a enable foreign key constraints command.
+     *
+     * @return string
+     */
+    public function compileEnableForeignKeyConstraints()
+    {
+        return 'SET FOREIGN_KEY_CHECKS=1;';
+    }
+
+    /**
+     * Compile a disable foreign key constraints command.
+     *
+     * @return string
+     */
+    public function compileDisableForeignKeyConstraints()
+    {
+        return 'SET FOREIGN_KEY_CHECKS=0;';
+    }
+
     /**
      * Create the column definition for a char type.
      *

src/Illuminate/Database/Schema/Grammars/PostgresGrammar.php

@@ -226,6 +226,26 @@ public function compileDropForeign(Blueprint $blueprint, Fluent $command)
         return "alter table {$table} drop constraint {$index}";
     }
 
+    /**
+     * Compile a enable foreign key constraints command.
+     *
+     * @return string
+     */
+    public function compileEnableForeignKeyConstraints()
+    {
+        return 'SET CONSTRAINTS ALL IMMEDIATE;';
+    }
+
+    /**
+     * Compile a disable foreign key constraints command.
+     *
+     * @return string
+     */
+    public function compileDisableForeignKeyConstraints()
+    {
+        return 'SET CONSTRAINTS ALL DEFERRED;';
+    }
+
     /**
      * Compile a rename table command.
      *

src/Illuminate/Database/Schema/Grammars/SQLiteGrammar.php

@@ -294,6 +294,26 @@ public function compileRename(Blueprint $blueprint, Fluent $command)
         return "alter table {$from} rename to ".$this->wrapTable($command->to);
     }
 
+    /**
+     * Compile a enable foreign key constraints command.
+     *
+     * @return string
+     */
+    public function compileEnableForeignKeyConstraints()
+    {
+        return 'PRAGMA foreign_keys = ON;';
+    }
+
+    /**
+     * Compile a disable foreign key constraints command.
+     *
+     * @return string
+     */
+    public function compileDisableForeignKeyConstraints()
+    {
+        return 'PRAGMA foreign_keys = OFF;';
+    }
+
     /**
      * Create the column definition for a char type.
      *

src/Illuminate/Database/Schema/Grammars/SqlServerGrammar.php

@@ -246,6 +246,26 @@ public function compileRename(Blueprint $blueprint, Fluent $command)
         return "sp_rename {$from}, ".$this->wrapTable($command->to);
     }
 
+    /**
+     * Compile a enable foreign key constraints command.
+     *
+     * @return string
+     */
+    public function compileEnableForeignKeyConstraints()
+    {
+        return 'EXEC sp_msforeachtable @command1="print \'?\'", @command2="ALTER TABLE ? WITH CHECK CHECK CONSTRAINT all";';
+    }
+
+    /**
+     * Compile a disable foreign key constraints command.
+     *
+     * @return string
+     */
+    public function compileDisableForeignKeyConstraints()
+    {
+        return 'EXEC sp_msforeachtable "ALTER TABLE ? NOCHECK CONSTRAINT all";';
+    }
+
     /**
      * Create the column definition for a char type.
      *