How to get tabloid

List,

I have a temporary table and I need to get the tableoid from the interface.
The table may not have any data in it so something like SELECT tableoid FROM
tmp_table LIMIT 1, returns zero when there is no data in the table. I know
that you can get information like this from the system catalogs but don't
know how to join them to accomplish this. Is there a diagram available which
shows the system catalog relationships and does anyone have a simple sql
string that will give me the tableoid of a given table.

TIA

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