Mysql substring extraction using delimiter

Question

I want to extract the substrings from a string in mysql. The string contains multiple substrings separated by commas(','). I need to extract these substrings using any mysql functions.

For example :

Table Name: Product
-----------------------------------
item_code  name    colors
-----------------------------------
102        ball     red,yellow,green
104        balloon  yellow,orange,red  

I want to select the colors field and extract the substrings as red,yellow and green as separated by comma.

Answer 1

Check the use of SPLIT_STR function here at line 64 to 69

Answer 2

Based on https://blog.fedecarg.com/2009/02/22/mysql-split-string-function/, here is a way to access a value from a delimiter separated array:

/*
  usage:
    SELECT get_from_delimiter_split_string('1,5,3,7,4', ',',  1); -- returns '5'
    SELECT get_from_delimiter_split_string('1,5,3,7,4', ',',  10); -- returns ''
*/
CREATE FUNCTION get_from_delimiter_split_string(
  in_array varchar(255),
  in_delimiter char(1),
  in_index int
)
RETURNS varchar(255) CHARSET utf8mb4 COLLATE utf8mb4_unicode_ci
RETURN REPLACE( -- remove the delimiters after doing the following:
  SUBSTRING( -- pick the string
    SUBSTRING_INDEX(in_array, in_delimiter, in_index + 1), -- from the string up to index+1 counts of the delimiter
    LENGTH(
      SUBSTRING_INDEX(in_array, in_delimiter, in_index) -- keeping only everything after index counts of the delimiter
    ) + 1
  ),
  in_delimiter,
  ''
);

here are the docs for the string operators for reference: https://dev.mysql.com/doc/refman/8.0/en/string-functions.html

Answer 3

A possible duplicate of this: Split value from one field to two

Unfortunately, MySQL does not feature a split string function. As in the link above indicates there are User-defined Split function.

A more verbose version to fetch the data can be the following:

SELECT SUBSTRING_INDEX(SUBSTRING_INDEX(colors, ',', 1), ',', -1) as colorfirst,
       SUBSTRING_INDEX(SUBSTRING_INDEX(colors, ',', 2), ',', -1) as colorsecond
....
       SUBSTRING_INDEX(SUBSTRING_INDEX(colors, ',', n), ',', -1) as colornth
  FROM product;