Equivalent of DB2 function "decimal(numeric expression, precision, scale)" in PostgreSQL

Question

Is there an equivalent of the DB2 function decimal(numeric expression, precision, scale) in PostgreSQL? Or how would I do this functionality in PostgreSQL?

The DECIMAL function returns a decimal representation of a character-string. The value of this second argument specifies the precision of the result. The scale value specifies the scale of the result (not sure what that means?).

Answer 1

Seems like that is a different way of writing a cast:

select cast('3.1415926535897932384626433832795' as decimal(12,4)) as pi

returns:

 pi
--------
 3.1416

And

select cast('3.1415926535897932384626433832795' as decimal(12,6)) as pi

returns:

 pi
----------
 3.141593

• András Váczi: You can also use the :: casting operator (in my view, that is a bit more readable). Also, just for the completeness, numeric is a synonym for decimal (or the other way around, if you like).