Re: FW: performance issue with a 2.5gb joinded table

Heikki Linnakangas <hlinnakangas@vmware.com> writes:
> One difference is that numerics are stored more tightly packed on
> Oracle. Which is particularly good for Oracle as they don't have other
> numeric data types than number. On PostgreSQL, you'll want to use int4
> for ID-fields, where possible. An int4 always takes up 4 bytes, while a
> numeric holding an integer value in the same range is typically 5-9 bytes.

Replacing those numeric(8) and numeric(16) fields with int4 and int8
would be greatly beneficial to comparison and hashing performance,
not just table size.  I'm a bit surprised that EDB's porting tools
evidently don't do this automatically (I infer from the reference to
PPAS that the OP is using EDB ...)

            regards, tom lane