How to read the value of a row field whose name is in another field

Question

I have a variable A with the name of a column from table TABLE, and I have a row B from TABLE how can I do something like value := B.A in plpgsql in Postgresql

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score 1 · Accepted Answer · answered Nov 27 '17 at 15:02

You need dynamic SQL with EXECUTE to parameterize any identifiers. And pass the row value as data with the USING clause Like:

EXEXUTE format('SELECT $1.%I ', A)
USING B
INTO  value_variable; -- with matching data type!

EXECUTE...INTO...USING statement in PL/pgSQL can't execute into a record?

How to read the value of a row field whose name is in another field

1 Answers1