# TransactionRollback

Rollback the current transaction and discard all unpersisted queries.

Only the changes made since the last `transactionSetSavepoint()` or `transactionCommit()` call will be discarded.

If no transaction is found in the current context, this method will throw an exception.

## Method Signature

```
TransactionRollback(savepoint=[string])
```

### Arguments

| Argument    | Type     | Required | Description                                                                                               | Default |
| ----------- | -------- | -------- | --------------------------------------------------------------------------------------------------------- | ------- |
| `savepoint` | `string` | `false`  | String name of the savepoint to rollback to. If not provided, the entire transaction will be rolled back. |         |

## Examples

### Using TransactionRollback with TransactionCommit

This simple example shows two JDBC queries executed inside a transaction. The first query, an INSERT, is committed to the database while the second is rolled back.

```java
transaction {
    queryExecute( "INSERT INTO vehicles (id,make) VALUES (8, 'Ford' )", {}, { datasource : "carDB" } );
    transactionCommit();

    queryExecute( "UPDATE developers SET name = 'Chevrolet' WHERE id=8", {}, { datasource : "carDB" } );
    transactionRollback();
}
```

Note that the rollback cannot affect the INSERT statement, since it has already been committed ("persisted") to the database.

#### Using TransactionRollback with TransactionSetSavepoint

Many times, you may wish to roll back only a portion of a transaction. This is possible by setting a "savepoint" upon the transaction:

```java
transaction {
    queryExecute( "INSERT INTO vehicles (id,make) VALUES (8, 'Ford' )", {}, { datasource : "carDB" } );
    transactionSetSavepoint( 'insert' );

    queryExecute( "UPDATE developers SET name = 'Chevrolet' WHERE id=8", {}, { datasource : "carDB" } );
    transactionRollback( 'insert' );
}
```

Multiple savepoints can be set or referenced.

### Script Syntax

In this code, any error triggered will cause transactionRollback() to run and roll back the pending transaction

[Run Example](https://try.boxlang.io/?code=eJxLqrAqKUrMK05MLsnMz1Oo5uIsKaoEUZz6%2BgrJ%2BSmpCiX5CkWleUABJHXO%2Bbm5mSUamtZcnLUKyYklyRkKGol5lQqpmmCtSCqD8nNykhKTsyFquWq5AC39I%2Bw%3D)

```java
bx:transaction {
	try {
		// code to run
		transactionCommit();
	} catch (any e) {
		transactionRollback();
	}
}

```

## Related

* [IsInTransaction](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/jdbc/isintransaction)
* [IsWithinTransaction](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/jdbc/iswithintransaction)
* [PreserveSingleQuotes](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/jdbc/preservesinglequotes)
* [QueryExecute](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/jdbc/queryexecute)
* [TransactionCommit](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/jdbc/transactioncommit)
* [TransactionSetSavepoint](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/jdbc/transactionsetsavepoint)