SELECT department, STRING_AGG(employee_name) FROM employees GROUP BY department;

SELECT department, STRING_AGG(employee_name, ', ') FROM employees GROUP BY department;

STRING_AGG requires delimiter as second parameter.

Always specify delimiter: STRING_AGG(column, delimiter)

High

Missing delimiter parameter

SELECT department, GROUP_CONCAT(employee_name, ', ') FROM employees GROUP BY department;

SELECT department, GROUP_CONCAT(employee_name SEPARATOR ', ') FROM employees GROUP BY department;

MySQL uses SEPARATOR keyword, not comma.

MySQL: GROUP_CONCAT(column SEPARATOR delimiter)

High

Wrong MySQL syntax