There are three PostgreSQL character types:
char: fixed length. varchar: variable length with optional limit. text: variable length without limit. char and varchar need an argument n to specify the characters length or limit.
char(n) The char(n) type stores fixed length strings.
If the string you are adding is shorter than n, spaces are added to make up the difference. For example, if ‘n’ is 7 and the string is house, which has 5 characters, the following value will be added: house .