ASA SQL Reference
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SIMILAR function [String]

Function 

Returns a number indicating the similarity between two strings.

Syntax 

SIMILAR ( string-expression-1, string-expression-2 )

Parameters 

string-expression-1    The first string to be compared.

string-expression-2    The second string to be compared.

Usage 

The function returns an integer between 0 and 100 representing the similarity between the two strings. The result can be interpreted as the percentage of characters matched between the two strings. A value of 100 indicates that the two strings are identical.

This function can be used to correct a list of names (such as customers). Some customers may have been added to the list more than once with slightly different names. Join the table to itself and produce a report of all similarities greater than 90 percent but less than 100 percent.

Standards and compatibility 

• SQL/92    Vendor extension.

• SQL/99    Vendor extension.

• Sybase    Not supported by Adaptive Server Enterprise.

Example 

The following statement returns the value 75.

SELECT SIMILAR( 'toast', 'coast' )

This signifies that the two values are 75% similar.