Error 4964



Message text

Lock scheme conversion failed due to insufficient SQL Server memory. Please retry later when there is less load/users on the SQL server, or ask your System Administrator to reconfigure SQL Server with more memory.


Adaptive Server provides two data locking schemes:

Since neither scheme locks index pages, they are referred to together as the data-only-locking (DOL) scheme.

An additional locking scheme, known as all-pages-locking (APL), locks the data and index pages affected by queries. APL is the default locking scheme.

When you use the alter table command to change a table’s locking scheme from one lock scheme to other lock scheme, Adaptive Server creates memory structures to build a new table with the desired locking scheme and transfers data from the existing table.

Error 4964 indicates that there is not enough memory available in Adaptive Server’s data cache to effect the lock scheme change. The problem can occur at various stages of table conversion when:


Check the activity on your server and retry the lock scheme conversion when there is less load on the system.

If the problem persists, check the memory allocation on your server. You may need to increase the memory allocated to the data cache.

Use sp_configure to view the current values of memory-related parameters on your system:

1> sp_configure "Memory Use"
2> go

Refer to “Configuring Memory” in the System Administration Guide: Volume 2 for details on monitoring and adjusting memory allocation parameters.

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