Concatenate in PostgreSQL

Question

I have a table with width and height (both integers). I want to display it as are. For eg: width = 300 and height = 160. Area = 300 x 160. I am using the following query

  select cast(concat(width,'x',height) as varchar(20)) from table;

or

select concat(width,'x',height) from table;

but I am getting the following error.

ERROR: function concat(character varying, "unknown", character varying) does not exist

Hint: No function matches the given name and argument types. You may need to add explicit type casts.

Can anyone tell me how to do this? Thanks

Answer 1

Use || as per: https://www.postgresql.org/docs/current/static/functions-string.html

select width || 'x' || height from table;

Sample fiddle: http://sqlfiddle.com/#!15/f10eb/1/0