Question

Say, there are two tables. One contains a field with long text values (for example foobarbaz), the other one contains shorter values (foobar and someothertext). I’d like to retrieve values from two tables with the following condition: the text must not be equal, but the beginning of the long string must match the short string. Is there a (neat) way to do this in Postgres? Thanks in advance.

Answer 1

How about:

SELECT <whatever>
  FROM <your tables>
 WHERE one_field <> the_other_field
   AND position(the_other_field in one_field) = 1;

See string functions and operators.