Question

Can I select a field/column from data type?

Postgres 7.4 (yep we are upgrading)

SELECT *
FROM tbl_name
WHERE tbl_name.column = 'timestamp with time zone'

Answer 1

That requires metadata.

select column_name
from information_schema.columns
where table_schema='your_schema'
and table_name='tbl_name'
and data_type='timestamp without time zone'
order by ordinal_position;

ETA: If you want the actual data from the table with column names matching the list above, you could probably set up a user-defined function that would grab those column names, put them in a comma-delimited list, and parse the query from tbl_name appropriately (of course, this is a lot easier if you’re working in a scripting language slightly outside of the database).