onmode and c arguments: Force a checkpoint (SQL administration API)

Use the onmode and c arguments with the admin() or task() function to force a checkpoint.

Syntax


1  EXECUTE FUNCTION
1 admin
1 task
2  (
2  "onmode" , "c"  , 
1 "block"
1! "hard"
1 "norm"
1 "unblock"
3  ) ;

Usage

This function forces a checkpoint that flushes the buffers to disk. You can use the c option to force a checkpoint if the most recent checkpoint record in the logical log was preventing the logical-log file from being freed (status U-B-L).

Use the block argument to prevent the database server from processing any transactions. Use this option to perform an external backup on Informix®. While the database server is blocked, users cannot access it, except in read-only mode. No transactions can complete until the database server is unblocked.

Use the hard argument to force a blocking checkpoint. This is the default.

Use the norm argument to force a nonblocking checkpoint.

Use the unblock argument to unblock the database server. When the database server is unblocked, data transactions and normal database server operations can resume. Use this option after you complete an external backup on Informix®.

This function is equivalent to the onmode -c command.

Example

The following example starts a blocking checkpoint:
EXECUTE FUNCTION task("onmode","c","hard");