from string to table...?

let's say you have the name of a table in a string.

'mytable'

you also have field names, such as

'lookupfield' 'valuefield'

which would be assembled like this

select valuefield from mytable where lookupfield = '?'

is there a way to write sql/plpgsql that'll take a varchar
argument (table and field names) and be able to turn it into the
appropriate query?

i can see pg_class contains table info and pg_attribute has info
for the fields ... is there a way (oids maybe?) to direct
postgres to the right table for a search, given the name of the
table in a varchar string? (and if so, how? :)

--
It is always hazardous to ask "Why?" in science, but it is often
interesting to do so just the same.
-- Isaac Asimov, 'The Genetic Code'

will(at)serensoft(dot)com
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