This query will run quite slow if tables are large, so - you may in addition create a trigger-updated TIMESTAMP columns and search for changed data through the recent created/updated elements only.
On May 11, 11:06 pm, "L. Berger" <straightfwd...@gmail.com> wrote: > Hello > > I havetwotables-- A and B. The structure of both is thesame. Only, > B has many indexes and is used for heavy duty SELECTs. On theother > hand, A only accepts heavy duty INSERTs, so has onlyoneprimary key > index. > > So my DB design is such that A is only an INSERT table. Periodically, > say every 20 minutes or so, I would like to take all the new INSERTs > from table A and put them into B. > > Is there any clever command to accomplish this? I'd rather not write a > PHP script with SQL to take every single new record, and update every > column of a new row in table B. For instance, can I do a replication > of onlytables, not databases? > > Thanks for any pointers!! > > LB
Assuming ID is PK:
INSERT INTO b SELECT * FROM a WHERE NOT EXISTS ( SELECT 1 FROM b WHERE b.ID = a.ID )
---------------------------(end of broadcast)--------------------------- TIP 9: In versions below 8.0, the planner will ignore your desire to choose an index scan if your joining column's datatypes do not match
