Re: chr(3) and 3::text

The convention here is to bottom or inline post, trimming unnecessary content.

Its that way because :: is defined to make it that way. 

 

3 has a type of integer

'3' has a type of text

::<type> is the PostgreSQL type casting operator that casts its left to to <type> (see the documentation I linked to)

So:

integer::text == text

cast(integer as text) == text

is the SQL Standard equivalent expression

David J.

integer::text == text, but which character 0x03 or 0x33 ?

Text should contain characters.

Characters is from character set.

Character 0x03 is valid in ASCII and UTF-8 character sets.