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SQL Server Help: Selecting Left and Right SubStrings of Strings in Transact-SQL

The Transact SQL Left and Right functions can be used to truncate strings after a certain number of characters from the left and right of the string, respectively. Each of these functions requires two arguments:

• The string from which the substring should be extracted.
• The length of the string to return.

The example below for the Northwind sample SQL Server database uses the Left function to create a three character ProductCode column from the first three characters of the ProductName column:

SELECT ProductName, LEFT(ProductName, 3) AS ProductCode FROM Products

Similarly, the Right function truncates strings at a certain length from the right hand side of that string. The following example produces a three character ProductCode column from the final three characters of the ProductName column:

SELECT ProductName, RIGHT(ProductName, 3) AS ProductCode FROM Products

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