Error 2630



Message text

In database '%1!', page %2! is linked backward to page %3!, but that page is linked forward to page %4!. Please report this internal error to Sybase Technical Support.


In the course of updating (or deleting) data, all of the rows may be moved off a page and then this page would be deallocated. When removing a page from the page chain, Adaptive Server checks to see if the previous pointer is consistent. The 2630 error is raised when Adaptive Server discovers that the previous page pointer is pointing to a page that should have its forward pointer pointing back to the page that pointed to it. This only occurs on data-only-locked (DOL) tables.


To resolve the error:

  1. Identify the object using one of the pages identified in the message by following the procedure in “Finding an object name from a page number” in the most recent Troubleshooting and Disaster Recovery guide.

    WARNING! The dbcc commands listed below are undocumented and nonstandard commands. The commands are provided “as is” without any warranty. Sybase Technical Support does not support these commands for general use. Although the command syntax is provided here for reference, use these commands only in the specific diagnostic situations and with the specific syntax shown in this section. Failure to do so could cause performance problems or database corruption.

    For example:

    dbcc traceon (3604)
    dbcc page (<database name>, <page-number>)

    NoteIn version 15.0.2 and later use:

    set switch on 3604

    to allow output to appear to your terminal device.

  2. If the page is a data page (the index ID = 0(zero)), drop and recreate the clustered index on the table. Or, use select into a new table from this table, or bcp out.

    If the page is an index page (the index ID is greater than 0(zero)), drop and recreate the index. Run dbcc tablealloc on the table to verify that the problem is corrected.

Additional information

This error may be caused by a hardware problem. If 2630 errors persist, start Adaptive Server with trace flags – T12617 – T12618 – T3605 to collect additional information and if necessary, contact Sybase Technical Support.

Versions in which this error is raised

Version 12.5.1 and later