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CursorLock

Description

When used with the CursorScroll parameter, specifies locking options for cursors in ODBC data source.

The values you can set for CursorLock control two aspects of cursor locking:

  • Concurrent access

    Ensures that multiple users can simultaneously access data that is accurate and current.

  • Collision detection

    Detects collisions that occur when multiple users update the same data at the same time.

Applies to

ODBC (if driver and back-end DBMS support this feature)

Syntax

CursorLock='lock_value'

Parameter

Description

lock_value

Specifies the type of locking you want to use for ODBC cursors. Values are:

  • Lock

    Use the lowest level of locking sufficient to allow updates on table rows.

  • Opt

    Use optimistic concurrency control. This means that table rows are not locked against updates by other users. To detect collisions, compare row versions or timestamps.

  • OptVal

    Use optimistic concurrency control. This means that table rows are not locked against updates by other users. To detect collisions, compare selected values with their previous values.

  • ReadOnly

    Prohibit updates on table rows by any user.

    For more about how the ODBC standard defines lock values, see your ODBC documentation.


Default value

If you do not specify a value for CursorLock, PowerBuilder defaults to the cursor lock setting specified by your ODBC driver.

Examples

To set scrolling and locking options for cursors in an ODBC data source:

  • Database profile

    On the Transaction page in the Database Profile Setup dialog box, select Dynamic Scrolling from the Scrolling Options drop-down list, and Optimistic Using Values from the Locking drop-down list.

  • Application

    Type the following in code:

    SQLCA.DBParm = "CursorScroll='Dynamic',CursorLock='OptVal'"

See also

CursorScroll

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