lct_admin

Description

Manages the last-chance threshold (LCT). It returns the current value of the LCT and aborts transactions in a transaction log that has reached its LCT.

Syntax

lct_admin({{"lastchance" | "logfull" | "reserved_for_rollbacks"},
	database_id
	|"reserve", {log_pages | 0 }
	| "abort", process-id [, database-id]})

Parameters

Examples

Example 1

Creates the log segment last-chance threshold for the database with dbid 1. It returns the number of pages at which the new threshold resides. If there was a previous last-chance threshold, it is replaced:

select lct_admin("lastchance", 1)

Example 2

Returns 1 if the last-chance threshold for the database with dbid of 6 has been crossed, and 0 if it has not:

select lct_admin("logfull", 6)

Example 3

Calculates and returns the number of log pages that would be required to successfully dump the transaction log in a log containing 64 pages:

select lct_admin("reserve", 64)

-----------
         16 

Example 4

Returns the current last-chance threshold of the transaction log in the database from which the command was issued:

select lct_admin("reserve", 0)

Example 5

Aborts transactions belonging to process 83. The process must be in log-suspend mode. Only transactions in a transaction log that has reached its LCT are terminated:

select lct_admin("abort", 83)

Example 6

Aborts all open transactions in the database with dbid of 5. This form awakens any processes that may be suspended at the log segment last-chance threshold:

select lct_admin("abort", 0, 5)

Example 7

Determines the number of pages reserved for rollbacks in the pubs2 database, which has a dbid of 5:

select lct_admin("reserved_for_rollbacks", 5, 0)

Example 8

Describes the free space available for a database with a dbid of 4:

select lct_admin("logsegment_freepages", 4)

Usage