SQL Server CONVERT() Function

The SQL Server CONVERT() function is used to convert a value of one data type to another data type. It is very useful in data processing, allowing us to convert one type of data to another and better compare and operate with other data.

Syntax

CONVERT(data_type, expression, [style])

data_type: The target data type to convert the expression to.
expression: The expression or column name to convert.
style: An optional parameter used to specify the style of the date and time types.

Use cases

The CONVERT() function is commonly used in the following scenarios:

Using different data types in a query.
Comparing or operating on data with different data types.
Converting date and time data types from one format to another.

Examples

Example 1: Convert a string to a number

SELECT CONVERT(INT, '123') AS Result;

Result:

Example 2: Convert a date to a different format

SELECT CONVERT(VARCHAR(10), GETDATE(), 101) AS Result;