Re: Column order performance

Bill,

> Does the order of columns of varying size have any effect on
> SELECT/INSERT/UPDATE/and/or/DELETE performance? Take the example where
> an integer primary key is listed first in the table and alternatively
> listed after some large varchar or text columns?

No, the "order" of the columns in the table makes no difference. They are not
physically stored in the metadata order, anyway; on the data pages,
fixed-length fields (e.g. INT, BOOLEAN, etc.) are stored first and
variable-length fields (CHAR, TEXT, NUMERIC) after them, AFAIK.

The only thing I have seen elusive reports of is that *display* speed can be
afffected by column order (e.g. when you call the query to the command line
with many rows) but I've not seen this proven in a test case.

--
Josh Berkus
Aglio Database Solutions
San Francisco