I have a table with a 3 column key.  I noticed that when I update a non-key field
in a record of the table that the update was taking longer than I thought it 
should.  After much experimenting I discovered that if I changed the data
types of two of the key columns to FLOAT8 that I got vastly improved

Orignally the data types of the 3 columns were FLOAT4, FLOAT4 and INT4.
My plaform is a PowerPC running Linux.  I speculated that the performance
improvement might be because the PowePC is a 64 bit processor but when
I changed the column data types to INT8, INT8 and INT4 I din't see any
improvement.  I also ran my test code on a Pentium 4 machine with the same
results in all cases.

This doesn't make any sense to me.  Why would FLOAT8 keys ever result
in improved performance?

I verified with EXPLAIN that the index is used in every case for the update.

My postmaster version is 7.1.3.

Any help will be greatly appreciated.

Medora Schauer
Sr. Software Engineer

Fairfield Industries
14100 Southwest Freeway
Suite 600
Sugar Land, Tx  77478-3469


---------------------------(end of broadcast)---------------------------
TIP 8: explain analyze is your friend

Reply via email to