Query a select that returns all the fields of an specific value of primary key without knownig the name of the single column's primary key?

Hi!
I need to query a select that returns all the fields of an specific primary key, but I don't have the single column's name that is constrained as primary key.
How can I do that?
Something like:
SELECT * FROM myTable WHERE myTable.pkey = 'foo';

Thanks

Carlos Henrique Iazzetti Santos
Compels Informática
Santa Rita do Sapucaí - MG
www.compels.net

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