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By default, any change you make to the database using ADO is committed as soon as it is executed. This includes explicit updates, as well as the UpdateBatch method on a Recordset. However, the previous section illustrated that you can use the BeginTrans and RollbackTrans or CommitTrans methods on the Connection object to use transactions.
The transaction isolation level is set as a property of the Connection object. The IsolationLevel property can take on one of the following values:
| ADO isolation level | Constant | SQL Anywhere level |
|---|---|---|
| Unspecified | adXactUnspecified | Not applicable. Set to 0 |
| Chaos | adXactChaos | Unsupported. Set to 0 |
| Browse | adXactBrowse | 0 |
| Read uncommitted | adXactReadUncommitted | 0 |
| Cursor stability | adXactCursorStability | 1 |
| Read committed | adXactReadCommitted | 1 |
| Repeatable read | adXactRepeatableRead | 2 |
| Isolated | adXactIsolated | 3 |
| Serializable | adXactSerializable | 3 |
| Snapshot | 2097152 | 4 |
| Statement snapshot | 4194304 | 5 |
| Readonly statement snapshot | 8388608 | 6 |
For more information on isolation levels, see Isolation levels and consistency.