CHAR_MATCHCOUNT - MaxCompute - Alibaba Cloud Documentation Center

The CHAR_MATCHCOUNT function of MaxCompute calculates the number of characters that are the same between two specified strings. This topic describes the syntax and parameters of the CHAR_MATCHCOUNT function. This topic also provides examples on how to use this function.

Syntax

bigint char_matchcount(string <str1>, string <str2>)

Parameters

str1 and str2: required. Values of the STRING type. The values must be valid UTF-8 strings. If invalid characters (non-Unicode-encoded characters) are found during the comparison of the two strings, this function returns 0.

Return value

A value of the BIGINT type is returned. If the value of str1 or str2 is null, null is returned.

Examples

Example 1: Calculate the number of characters that belong to the string aabc and appear in the string abcde. Sample statement:
```
-- The return value is 4. 
select char_matchcount('aabc','abcde');
```

Example 2: An input parameter is set to null. Sample statement:

-- The return value is null. 
select char_matchcount(null,'abcde');

Related functions

CHAR_MATCHCOUNT is a string function. For more information about functions related to string searches and conversion, see String functions.