sql - Select columns with particular column names in PostgreSQL

Question

I want to write a simple query to select a number of columns in PostgreSQL. However, I keep getting errors - I tried a few options but they did not work for me. At the moment I am getting the following error:

org.postgresql.util.PSQLException: ERROR: syntax error at or near "column"

To get the columns with values I try the followig:

select * from weather_data where column like '%2010%'

Any ideas?

Answer 1

column is a reserved word. You cannot use it as identifier unless you double-quote it. Like: "column".

Doesn't mean you should, though. Just don't use reserved words as identifiers. Ever.

To ...

select a list of columns with 2010 in their name:

.. you can use this function to build the SQL command dynamically from the system catalog table pg_attribute:

CREATE OR REPLACE FUNCTION f_build_select(_tbl regclass, _pattern text)
  RETURNS text AS
$func$
    SELECT format('SELECT %s FROM %s'
                 , string_agg(quote_ident(attname), ', ')
                 , $1)
    FROM   pg_attribute 
    WHERE  attrelid = $1
    AND    attname LIKE ('%' || $2 || '%')
    AND    NOT attisdropped  -- no dropped (dead) columns
    AND    attnum > 0;       -- no system columns
$func$ LANGUAGE sql;

Call:

SELECT f_build_select('weather_data', '2010');

Returns something like:

SELECT foo2010, bar2010_id, FROM weather_data;

You cannot make this fully dynamic, because the return type is unknown until we actually build the query.