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MySQLSUBSTR() Function

Example

Extract a substring from a string (start at position 5, extract 3 characters):

SELECT SUBSTR("SQL Tutorial", 5, 3) AS ExtractString;
Try it Yourself »

Definition and Usage

The SUBSTR() function extracts a substring from a string (starting at any position).

Note: The position of the first character in the string is 1.

123456789101112
SQL Tutorial

Note: The position of the last character in the string is -1.

-12-11-10-9-8-7-6-5-4-3-2-1
SQL Tutorial

Note: The SUBSTR() andMID() functions equals to theSUBSTRING() function.

Syntax

SUBSTR(string,start,length)

OR:

SUBSTR(string FROMstart FORlength)

Parameter Values

ParameterDescription
stringRequired. The string to extract from
startRequired. The start position. Can be both a positive or negative number. If it is a positive number, this function extracts from the beginning of the string. If it is a negative number, this function extracts from the end of the string. The position of the first character in the string is 1 and the position of the last character in the string is -1
lengthOptional. The number of characters to extract. If omitted, the whole string will be returned (from thestart position)

Technical Details

Works in:From MySQL 4.0

More Examples

Example

Extract a substring from the text in a column (start at position 2, extract 5 characters):

SELECT SUBSTR(CustomerName, 2, 5) AS ExtractString
FROM Customers;
Try it Yourself »

Example

Extract a substring from a string (start from the end, at position -5, extract 5 characters):

SELECT SUBSTR("SQL Tutorial", -5, 5) AS ExtractString;
Try it Yourself »


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