How to Sort Values in GROUP_CONCAT Statements?

Sorting Values in GROUP_CONCAT Statements

The GROUP_CONCAT function in MySQL enables you to concatenate values grouped by a specified column. However, by default, the values are not sorted. To address this, there is a straightforward solution.

Solution:

The syntax of GROUP_CONCAT with sorting capabilities is:

GROUP_CONCAT(DISTINCT <expression> ORDER BY <order_expression> <direction> SEPARATOR <separator>)

Where:

• : The values to be concatenated
• : The column or expression used for sorting
• : The sorting direction (ASC or DESC)
• : The delimiter used to separate the concatenated values

Example:

In the provided query, to sort the concatenated values alphabetically, you can modify it as follows:

GROUP_CONCAT((SELECT GROUP_CONCAT(parent.name SEPARATOR " » ") 
FROM test_competence AS node, test_competence AS parent 
WHERE node.lft BETWEEN parent.lft AND parent.rgt 
  AND node.id = l.competence 
  AND parent.id != 1 
GROUP BY parent.id
ORDER BY parent.name) SEPARATOR "<br />\n") AS competences

By specifying ORDER BY parent.name within the subquery, the values will be sorted alphabetically before being concatenated. This will output the desired result:

Administration » Organization

Crafts » Joinery

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