---
url: >-
  /statelake/scripting-reference/classes/data-definition-class-tflodatasource/tflodatasource.rollbacktran.md
---

# TFloDataSource.RollbackTran

This rolls back a new database transaction that was started using **StartTransaction** against the **Data Definition**.

Database transactions are handled automatically so you do not normally need to use this function unless you want specific control over database transactions.

Any transactions you start with **StartTransaction** will need to be finalised by you with either **CommitTran** or **RollbackTran**.

**Declaration**: Function RollbackTran : boolean

This is a simple example.

```pascal
procedure OnMapEvent(var Value:Variant);
begin
 //Check the flag Global1 to determine whether you want the transaction
 //If not, then roll it back
 If Global1 = False then
    Dest.RollbackTran;
end;
```

And the following example illustrates the relationship between **RollbackTran** and **CommitTran**.

```pascal
procedure OnMapEvent(var Value:Variant);
begin
 //check that the transaction has started
 if Not Source.CommitTran then
 begin
    LogError('Unable to commit transaction');
 //If it fails to commit then you need to rollback
    Source.RollbackTran;
 end;
end;
```

For more information, please also refer to [TFloDataSource.StartTransaction](/statelake/scripting-reference/classes/data-definition-class-tflodatasource/tflodatasource.starttransaction) and [TFloDataSource.CommitTran](/statelake/scripting-reference/classes/data-definition-class-tflodatasource/tflodatasource.committran).