CAST

Converts a value to the specified data type.

PostgreSQL 17.5

CAST(value AS type)

Parameters

A value of the given type; a failed conversion is a query error

PostgreSQL 17.5

SELECT CAST('42' AS INTEGER) + 1 AS result;

result
43

PostgreSQL 17.5

SELECT CAST(12005.6 AS INTEGER) AS result;

result
12006

PostgreSQL 17.5

SELECT '42'::INTEGER * 2 AS result;

result
84

Type	Result
INTEGER, BIGINT	A whole number. A numeric fraction is rounded away from zero (2.5 → 3), a double precision one to even (2.5 → 2). A string must contain a whole number: '12abc' and '3.7' cause an error.
NUMERIC[(p, s)]	An exact number: s is the number of decimal places, extra ones are rounded; a number that does not fit into p digits is an error.
DOUBLE PRECISION	A floating-point number with about 15 significant digits.
TEXT, VARCHAR(n)	A string. VARCHAR(n) silently cuts the value to n characters.
DATE	A date; a string must contain an existing date, the time is dropped.
TIMESTAMP	A date with time, without a time zone.
BOOLEAN	A logical value; from strings it accepts 'true', 'false', 'yes', 'no', '1', '0'.

Instead of CAST(value AS type), you can write value::type.