Default Isolation Level
- Last Updated: January 16, 2024
- 1 minute read
- DataDirect Connectors
- ODBC
- Progress Openedge 8.0
Attribute
DefaultIsolationLevel (DIL)
Purpose
The method by which locks on data in the database are acquired and released.
Valid Values
0 | 1 | 2 |
3
Behavior
If set to 0 (READ UNCOMMITTED), other processes can be
read from the database. Only modified data is locked and is not released until the
transaction ends.
If set to 1 (READ COMMITTED) other processes can change a
row that your application has read if the cursor is not on the row you want to change. This
level prevents other processes from changing records that your application has changed until
your application commits them or ends the transaction.
If set to 2 (REPEATABLE READ), other processes are
prevented from accessing data that your application has read or modified. All read or
modified data is locked until transaction ends.
If set to 3 (SERIALIZABLE), other processes are prevented
from changing records that are read or changed by your application (including phantom
records) until your program commits them or ends the transaction. This level prevents the
application from reading modified records that have not been committed by another process.
If your application opens the same query during a single unit of work under this isolation
level, the results table will be identical to the previous table; however, it can contain
updates made by your application.
Refer to Locking and isolation levels in the Progress DataDirect for ODBC Drivers Reference for details.
Valid Values
Default
1 (READ COMMITTED)