Concatenating Multiple Rows From a Select Into a Single Line and Generating JSON From a Query [MySQL]

To concatenate multiple rows into one:

SELECT GROUP_CONCAT(COLUNA1) FROM TABELA;

So, to generate JSON from a query:

SELECT 
	CONCAT('[', 
		GROUP_CONCAT(
			CONCAT('{"coluna1":"', COLUNA1, '",'), 
			CONCAT('"coluna2":"', COLUNA2, '"}')
		)
	,']') AS JSON 
FROM TABELA;