MySQL Split String Function

喜旎果

　　http://blog.fedecarg.com/2009/02/22/mysql-split-string-function/
　　MySQL does not include a function to split a delimited string. However, it’s very easy to create your own function.
Create function syntax
　　A user-defined function is a way to extend MySQL with a new function that works like a native MySQL function.
CREATE [AGGREGATE] FUNCTION function_name　　
RETURNS {STRING|INTEGER|REAL|DECIMAL}
　　To create a function, you must have the INSERT privilege for the  database.
Split delimited strings
　　The following example function takes 3 parameters, performs an operation using an SQL function, and returns the result.
　　Function
CREATE FUNCTION SPLIT_STR(　　x VARCHAR(255),
　　delim VARCHAR(12),
　　pos INT
　　
)
　　
RETURNS VARCHAR(255)
　　
RETURN REPLACE(SUBSTRING(SUBSTRING_INDEX(x, delim, pos),
　　LENGTH(SUBSTRING_INDEX(x, delim, pos -1)) + 1),
　　delim, '');
　　Usage
SELECT SPLIT_STR(string, delimiter, position)　　Example
　　
SELECT SPLIT_STR('a|bb|ccc|dd', '|', 3) as third;　　
+-------+
　　
| third |
　　
+-------+
　　
| ccc   |
　　
+-------+