db2 學習筆記

db2 學習筆記

1。手工強制DB2歸檔

2。Not Logged Initially Option

3。BLK_LOG_DSK_FUL 參數

4。提高備份性能的參數PARALLELISM ,BACKBUFSZ

5。備份到磁盤上的文件名

1。手工強制DB2歸檔

db2 => ? archive log ?
ARCHIVE LOG FOR DATABASE database-alias [USER username [USING passWord]]
[On-DbPartitionNum-Clause]

On-DbPartitionNum-Clause:
  ON {{DBPARTITIONNUM | DBPARTITIONNUMS} (db-partition-number
  [TO  db-partition-number] , ... ) | ALL DBPARTITIONNUMS [EXCEPT
  {DBPARTITIONNUM | DBPARTITIONNUMS} (db-partition-number
  [TO db-partition-number] , ...)]}

2。Not Logged Initially Option

當用create talbe 或者alter talbe 語句帶上這個選項，表示不對表的insert或者update 記錄日志，特別對於導入大量的數據時，而且這些數據很容易重新創建時，這個選項尤其有用。

3。BLK_LOG_DSK_FUL 參數

The DBM configuration parameter BLK_LOG_DSK_FUL can be used to prevent "disk full" errors from being generated when DB2 cannot create a new log file in the active log path.

4。提高備份性能的參數PARALLELISM ,BACKBUFSZ

BACKUP DATABASE DB2CERT TO /dev/rmt0
　　　 WITH 2 BUFFERS
　　　 BUFFER 512
　　　 PARALLELISM 2

 This command backs up the database DB2CERT to a tape device on an AIX system. Two buffers of 512 (4 KB) pages each are allocated. Two parallel tasks are used to backup in parallel

• The value of the PARALLELISM parameter. Using this parameter can reduce the amount of time required to complete the backup. It defines the number of processes or threads that are started to read data from the database. Each process or thread is assigned to back up a specific table space. When it completes backing up the table space, it requests another. Increasing the value requires additional processor and memory resources. The default value is one.

• The backup buffer size and number of buffers. If you use multiple buffers and I/O channels, you should use at least twice as many buffers as channels to ensure that the channels do not have to wait for data. The size of the buffers should ideally be a multiple of the table space extent size. If you have differing extent sizes, choose a multiple of the largest extent size. If the buffer size if not specifIEd the value is taken from the database manager configuration parameter BACKBUFSZ, which by default is 1024 (4 KB) pages.

5。備份到磁盤上的文件名

SAMPLE.0.db2inst1.NODE0000.CATN0000.20050705103703.001