? CAST() Function in SQL

The CAST() function converts a value from one data type to another.

? Syntax

CAST(expression AS target_data_type)

• expression: The value or column you want to convert.

• target_data_type: The data type you want to convert to (e.g., INT, VARCHAR, DATE, etc.).

? Examples

1. Convert string to integer

SELECT CAST('123' AS INT);-- Returns 123 as integer

2. Convert integer to string

SELECT CAST(456 AS VARCHAR(10));-- Returns '456' as a string

3. Convert string to date

SELECT CAST('2023-06-06' AS DATE);-- Returns a DATE value

4. Using CAST in a query

SELECT employee_name, CAST(salary AS VARCHAR(20)) AS salary_textFROM employees;

? Key Points

• Standard SQL function supported by most databases (MySQL, PostgreSQL, SQL Server, Oracle).

• Useful for data type conversions in expressions and queries.

• Helps avoid errors when performing operations on incompatible data types.

Want to know about CONVERT() function (similar to CAST()) or examples with date/time casting?