postgres=#
postgres=#
postgres=# CREATE TABLE myTable (isbn text, in_stock boolean);
CREATE TABLE
postgres=#
postgres=# INSERT INTO myTable VALUES ('0385121679', true);
INSERT 0 1
postgres=# INSERT INTO myTable VALUES ('039480001X', 't');
INSERT 0 1
postgres=# INSERT INTO myTable VALUES ('044100590X', 'true');
INSERT 0 1
postgres=# INSERT INTO myTable VALUES ('0451198492', false);
INSERT 0 1
postgres=# INSERT INTO myTable VALUES ('0394900014', '0');
INSERT 0 1
postgres=# INSERT INTO myTable VALUES ('0441172717', '1');
INSERT 0 1
postgres=# INSERT INTO myTable VALUES ('0451160916');
INSERT 0 1
postgres=#
postgres=# select * from myTable;
isbn | in_stock
------------+----------
0385121679 | t
039480001X | t
044100590X | t
0451198492 | f
0394900014 | f
0441172717 | t
0451160916 |
(7 rows)
postgres=#
postgres=# -- Checking for 'false' Boolean values
postgres=#
postgres=# SELECT * FROM myTable WHERE in_stock = 'no';
isbn | in_stock
------------+----------
0451198492 | f
0394900014 | f
(2 rows)
postgres=#
postgres=#
postgres=#
postgres=# drop table myTable;
DROP TABLE
postgres=#
postgres=#