DB2 檢視 Snapshot的內容

Snapshot可以抓取某一個時間點下，monitor switches所收集的資料。因此在進行snapshot前，需先開啟monitor switches，這裡以lock的switch為例

db2 update monitor switches using lock on

接著查一下monitor  switch是否被打開了

db2 get monitor switches

確定LOCK的switch被打開後，執行下列指令，就可以抓取LOCK這個monitor switches所收集的資料了

db2 get snapshot for locks on db_name

以下為範例結果

Database Lock Snapshot

Database name                              = SAMPLE
Database path                              = C:\DB2\NODE0000\SQL00001\
Input database alias                       = SAMPLE
Locks held                                 = 5
Applications currently connected           = 1
Agents currently waiting on locks          = 0
Snapshot timestamp                         = 06-05-2002 17:08:25.048027

Application handle                         = 8
Application ID                             = *LOCAL.DB2.0098C5210749
Sequence number                            = 0001
Application name                           = db2bp.exe
CONNECT Authorization ID                   = DB2ADMIN
Application status                         = UOW Waiting
Status change time                         = Not Collected
Application code page                      = 1252
Locks held                                 = 5
Total wait time (ms)                       = 0

List Of Locks
 Lock Name                   = 0x02000300050000000000000052
 Lock Attributes             = 0x00000000
 Release Flags               = 0x00000001
 Lock Count                  = 1
 Hold Count                  = 0
 Lock Object Name            = 5
 Object Type                 = Row
 Tablespace Name             = USERSPACE1
 Table Schema                = DB2ADMIN
 Table Name                  = STAFF
 Mode                        = U

 Lock Name                   = 0x02000300000000000000000054
 Lock Attributes             = 0x00000000
 Release Flags               = 0x00000001
 Lock Count                  = 1
 Hold Count                  = 0
 Lock Object Name            = 3
 Object Type                 = Table
 Tablespace Name             = USERSPACE1
 Table Schema                = DB2ADMIN
 Table Name                  = STAFF
 Mode                        = IX

 Lock Name                   = 0x01000000010000000100810056
 Lock Attributes             = 0x00000000
 Release Flags               = 0x40000000
 Lock Count                  = 1
 Hold Count                  = 0
 Lock Object Name            = 0
 Object Type                 = Internal Variation Lock
 Mode                        = S

 Lock Name                   = 0x41414141414A48520000000041
 Lock Attributes             = 0x00000000
 Release Flags               = 0x40000000
 Lock Count                  = 1
 Hold Count                  = 0
 Lock Object Name            = 0
 Object Type                 = Internal Plan Lock
 Mode                        = S

 Lock Name                   = 0x434F4E544F4B4E310000000041
 Lock Attributes             = 0x00000000
 Release Flags               = 0x40000000
 Lock Count                  = 1
 Hold Count                  = 0
 Lock Object Name            = 0
 Object Type                 = Internal Plan Lock
 Mode                        = S

由上面的例子可以看到，目前資料有1個應用程式連接，而這個應用程式產生了5個lock，目前這個應用程式花費0秒在等lock