SQL Server ASCII() Function

The ASCII() function in SQL Server gets the ASCII (American Standard Code for Information Interchange) value of a character. ASCII is a numerical representation of characters, where each character has a unique numerical code.

ASCII(): Definition and Usage

This function is useful when you need to work with the underlying numerical representation of characters, perhaps for character comparisons, data validation, or specialized text processing.

Syntax

Syntax

ASCII(character)

Parameter Values

Parameter Description
character The character for which you want the ASCII value. Only the first character of the string is considered. This is required.

Example

Getting the ASCII Value of a Character

This example retrieves the ASCII value of the first character in the 'CustomerName' column from the 'Customers' table.

Syntax

SELECT ASCII(CustomerName) AS NumCodeOfFirstChar
FROM Customers;
Output

The query returns a table with a column 'NumCodeOfFirstChar' containing the ASCII value of the first character of each customer's name. 


NumCodeOfFirstChar
------------------
65  --(Example: If the first character is 'A')
66  --(Example: If the first character is 'B')
...

Technical Details

The ASCII() function is supported in:

  • SQL Server (starting with version 2008)
  • Azure SQL Database
  • Azure SQL Data Warehouse
  • Parallel Data Warehouse
**Note:** The example output assumes the existence of a 'Customers' table with a 'CustomerName' column. The `...` indicates that additional rows with ASCII values corresponding to the first character of each customer name would be returned. The specific values will depend on the data in your 'Customers' table.