modify chunk extend argument: Extend the size of a chunk (SQL administration API)

Use the modify chunk extend argument with the admin() or task() function to extend the size of the chunk by a specified minimum amount. The chunk must be marked as extendable.

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>>-EXECUTE FUNCTION--+-admin-+---------------------------------->

>--(--"--modify chunk extend--"--,--"chunk_number"--,--"extend_amount"--)-- ;-><

Element Description Key Considerations
chunk_number The number of the chunk.  
extend_amount The minimum amount of space in kilobytes to add to the chunk. See admin() and task() Argument Size Specifications.


You must mark a chunk as extendable before the chunk can be extended, either manually or automatically. Use the modify chunk extendable argument with the admin() or task() function to mark a chunk as extendable.

The modify chunk extend SQL administration API command is an alternative to the adm_add_storage task that the server can run to automatically extend the size of a chunk when the space containing the chunk runs low or out of free pages.

You cannot extend a chunk in a mirrored space, and you will receive an error if you provide the number of a mirror chunk when you run a modify chunk extend SQL administration API command.

To identify primary and mirror chunks in a mirrored space, look for the P (primary) or M (mirror) in position 1 of the flags field in onstat -d command output.

The server might round up the requested size, depending on the page size and the configured create size and extend size of the space.


Suppose that your onstat -d command output shows that chunk number 3 is a mirror chunk and chunk number 4 is a not a mirror chunk. You cannot extend the size of chunk number 3. However, you can modify chunk number 4. The following command extends the size of chunk number 4 by 10000 kilobytes:

EXECUTE FUNCTION task("modify chunk extend", "4", "10000");

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