DB2 has added a new keyword to the CREATE and ALTER TABLE SQL statements: APPEND. This new keyword enables a pretty simple concept. If you CREATE or ALTER a TABLE to APPEND YES, DB2 simply sticks the new row at the end of the table*, makes no attempt at searching for available space, and makes no effort to preserve any kind of clustering order. Because you can ALTER this attribute on and off, you can switch it on (YES) for that massive insert batch job you run once a month and always follow with REORG/RUNSTATS anyway, then switch it back off (NO) for your day to day online insert processing. REORG is unaffected by the APPEND option so you can use it in conjunction with a tables clustering options allowing the object to take advantage of a faster insert and still maintaining a clustered sequence by the REORG and LOAD utilities.
The APPEND will work for all tables except those created in LOB, XML, and work files table spaces. BTW, this process is for insert and online LOAD operations. There is also a new column, APPEND, in SYSIBM.SYSTABLES so you can track when this feature has been turned on or off. In addition, you are going to see some index relief for inserts in DB2 9. But I'll save that for another post.
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