how to use check constraint in postgresql for string

Question

i am new to postgres

how to create table with check constraint for column name say polluted which only have to accept 'yes' or 'no' values on insert.

for other values it should promote error message

My table name is vehicles

Why don't you use a `boolean` type? That would be a much better choice for a yes/no flag — , Jul 12 '18 at 07:04

score 16 · Accepted Answer · answered Jul 12 '18 at 07:07

16

Use an in condition.

create table vehicles
(
  id integer primary key, 
  polluted text not null check (polluted in ('yes', 'no'))
);

answered Jul 12 '18 at 07:07

your query working fine and also how to write constraint error message if other value is inserted – Ratan Uday Kumar Jul 12 '18 at 07:20

1 Answers1