Peter Eisentraut <peter_e@gmx.net> writes:
> An int4 field is required to be aligned at a 4-byte boundary internally, so
> there are 3 bytes wasted between tmp_A.c and tmp_A.i. If you switch the
> order of the fields you should see space savings.
Probably not, because the row-as-a-whole has alignment requirements too.
In this example you'll just move the pad bytes from one place to
another.
regards, tom lane