DB2 Version 9.7 for Linux, UNIX, and Windows

lock_current_mode - Original lock mode before conversion monitor element

During a lock conversion operation, the lock mode held by the application waiting to acquire the lock, before the conversion is completed.

Table 1. Table Function Monitoring Information
Table Function	Monitor Element Collection Command and Level
MON_GET_LOCKS table function - list all locks in the currently connected database
MON_GET_APPL_LOCKWAIT table function - get information about locks for which an application is waiting

Table 2. Snapshot Monitoring Information
Snapshot Level	Logical Data Grouping	Monitor Switch
Lock	lock	Basic
Lock	lock_wait	Basic

Table 3. Event Monitoring Information
Event Type	Logical Data Grouping	Monitor Switch
Locking	-	-
Deadlocks¹	lock	-
Deadlocks¹	event_dlconn	-

1: This option has been deprecated. Its use is no longer recommended and might be removed in a future release. Use the CREATE EVENT MONITOR FOR LOCKING statement to monitor lock-related events, such as lock timeouts, lock waits, and deadlocks.

Usage

The following scenario describes an example of lock conversion. During an update or delete operation it is possible to wait for an X lock on the target row. If the transaction is holding an S or V lock on the row, this would require a conversion. At this point, the lock_current_mode element is assigned a value of S or V, while the lock waits to be converted to an X lock.

The possible lock modes are listed in the following table.

Mode	Type of Lock	API Constant
	No Lock	SQLM_LNON
IS	Intention Share Lock	SQLM_LOIS
IX	Intention Exclusive Lock	SQLM_LOIX
S	Share Lock	SQLM_LOOS
SIX	Share with Intention Exclusive Lock	SQLM_LSIX
X	Exclusive Lock	SQLM_LOOX
IN	Intent None	SQLM_LOIN
Z	Super Exclusive Lock	SQLM_LOOZ
U	Update Lock	SQLM_LOOU
NS	Scan Share Lock	SQLM_LONS
NW	Next Key Weak Exclusive Lock	SQLM_LONW