{"id":"4a25b402ed274bd4","repo":"laravel/framework","slug":"this-database-driver-does-not-support-modifying-co","errorCode":null,"errorMessage":"This database driver does not support modifying columns.","messagePattern":"This database driver does not support modifying columns\\.","errorType":"exception","errorClass":"RuntimeException","httpStatus":null,"severity":"error","filePath":"src/Illuminate/Database/Schema/Grammars/Grammar.php","lineNumber":212,"sourceCode":"        return sprintf('alter table %s rename column %s to %s',\n            $this->wrapTable($blueprint),\n            $this->wrap($command->from),\n            $this->wrap($command->to)\n        );\n    }\n\n    /**\n     * Compile a change column command into a series of SQL statements.\n     *\n     * @param  \\Illuminate\\Database\\Schema\\Blueprint  $blueprint\n     * @param  \\Illuminate\\Support\\Fluent  $command\n     * @return list<string>|string\n     *\n     * @throws \\RuntimeException\n     */\n    public function compileChange(Blueprint $blueprint, Fluent $command)\n    {\n        throw new RuntimeException('This database driver does not support modifying columns.');\n    }\n\n    /**\n     * Compile a fulltext index key command.\n     *\n     * @param  \\Illuminate\\Database\\Schema\\Blueprint  $blueprint\n     * @param  \\Illuminate\\Support\\Fluent  $command\n     * @return string\n     *\n     * @throws \\RuntimeException\n     */\n    public function compileFulltext(Blueprint $blueprint, Fluent $command)\n    {\n        throw new RuntimeException('This database driver does not support fulltext index creation.');\n    }\n\n    /**\n     * Compile a drop fulltext index command.","sourceCodeStart":194,"sourceCodeEnd":230,"githubUrl":"https://github.com/laravel/framework/blob/bd6b5437e6ad87bb49f9b426724f07a9f64e9683/src/Illuminate/Database/Schema/Grammars/Grammar.php#L194-L230","documentation":"Base Grammar::compileChange() throws RuntimeException because the driver's grammar does not support modifying existing columns. compileChange is invoked when a migration calls $column->change() (e.g. $table->string('name')->change()). Drivers that support it override compileChange; SQLite historically did so via a temp-table rebuild, MySQL/Postgres/SQL Server natively.","triggerScenarios":"Calling ->change() on a column inside a migration on a driver whose grammar does not override compileChange; combining the doctrine/dbal dependency removal (Laravel 11+) with an older driver that lacks native ->change() support.","commonSituations":"Pre-Laravel-9 apps that relied on doctrine/dbal for ->change() and dropped DBAL after upgrade; custom/obscure drivers missing the override.","solutions":["Verify the connection is mysql/pgsql/sqlite/sqlsrv (all of which override compileChange in current Laravel).","On a custom driver, implement compileChange to emit the engine's ALTER COLUMN/ALTER TABLE syntax.","Rewrite the migration without ->change(): create a new column, backfill, drop old, rename.","Ensure doctrine/dbal is installed if your Laravel version still relies on it for ->change()."],"exampleFix":"// before\nSchema::table('users', fn (Blueprint $t) => $t->string('name', 100)->change());\n\n// after — manual SQL for an unsupported driver\nDB::statement('ALTER TABLE users MODIFY name VARCHAR(100)');","handlingStrategy":"type-guard","validationCode":"$grammar = Schema::getConnection()->getSchemaGrammar();\nif ((new \\ReflectionMethod($grammar, 'compileChange'))->getDeclaringClass()->getName()\n    === \\Illuminate\\Database\\Schema\\Grammars\\Grammar::class) {\n    throw new \\RuntimeException('->change() unsupported on '.DB::connection()->getDriverName());\n}\nSchema::table('users', fn (Blueprint $t) => $t->string('name', 100)->change());","typeGuard":"function driverSupportsColumnChange(): bool\n{\n    $g = Schema::getConnection()->getSchemaGrammar();\n\n    return (new \\ReflectionMethod($g, 'compileChange'))\n        ->getDeclaringClass()->getName() !== \\Illuminate\\Database\\Schema\\Grammars\\Grammar::class;\n}","tryCatchPattern":"try {\n    Schema::table('users', fn (Blueprint $t) => $t->string('name', 100)->change());\n} catch (\\RuntimeException $e) {\n    if (str_contains($e->getMessage(), 'modifying columns')) {\n        DB::statement('ALTER TABLE users MODIFY name VARCHAR(100)');\n    } else {\n        throw $e;\n    }\n}","preventionTips":["Use a first-class driver when relying on ->change().","Implement compileChange on custom grammars.","Keep doctrine/dbal installed on Laravel versions that still require it for ->change().","Prefer explicit SQL ALTER statements for unsupported drivers."],"tags":["schema","database","driver-support","grammar","migrations","alter-column"],"analyzedSha":"bd6b5437e6ad87bb49f9b426724f07a9f64e9683","analyzedAt":"2026-08-06T00:28:32.783Z","schemaVersion":2}