Question

I want to covert the result row from the select query into a comma-separated string. I have table in which there are 153 columns. the select query is like as follow

SELECT * FROM mytable where id = 3

I want all the resulting 153 columns of a row in a comma-separated string. Is there any trick in MySql?

Answer 1

You can use GROUP_CONCAT function to do that.

SELECT GROUP_CONCAT(col1, col2,..coln) FROM my_table;

EDIT:

get all column names with following query and the substitute that in CONCAT_WS function::

SELECT GROUP_CONCAT(COLUMN_NAME) 
FROM information_schema.COLUMNS 
WHERE TABLE_NAME = 'my_table';

SELECT CONCAT_WS(',', col1, col2, ..., coln) 
FROM my_table;

or try:

SET @query1 = CONCAT('
        SELECT CONCAT_WS(",", ',(SELECT GROUP_CONCAT(COLUMN_NAME)
                                 FROM information_schema.COLUMNS
                                 WHERE TABLE_NAME = 'my_table'),')
        FROM    tablew_name'
        );
PREPARE stmt FROM @query1; EXECUTE stmt; DEALLOCATE PREPARE stmt;