PostgreSQL Type Casts

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Published May 29, 2024
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In PostgreSQL, Type Casts converts a value from one data type to another specified data type. This can be done explicitly using the CAST() function and the :: operator.

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Syntax

CAST() function:

CAST(value AS target_data_type)

:: operator:

value::target_data_type

Examples

Example 1

Casting a floating-point number to an integer using the CAST() function:

SELECT CAST(37.8 AS INTEGER);

Output:

int4
38

Example 2

Casting a string to a date using the CAST() function:

SELECT CAST('Wed 22 May 2024 18:33:55' AS DATE);

Output:

date
2024-05-22

Example 3

Casting a string to a floating-point number using the :: operator:

SELECT '22.5'::FLOAT;

Output:

float8
22.5

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