Procedure.txt

DELIMITER $
CREATE OR REPLACE PROCEDURE usuario(
    IN id INT,
    IN nome VARCHAR(100),
    IN cpf VARCHAR(20),
    IN email VARCHAR(50),
    IN matricula VARCHAR(20),
    IN nivel VARCHAR(15),
    IN st CHAR(1))
	
    BEGIN
    	
        DECLARE variavel VARCHAR(1000) DEFAULT "";
        
        IF id != 0 THEN
        	SET	variavel = CONCAT("WHERE usuario_id = ", id);
        ELSE
        	SET	variavel = "WHERE usuario_id > 0";
		END IF;
        
        IF nome != "" THEN
        	SET	variavel = CONCAT(variavel, " AND usuario_nome = ", nome);
		END IF;
        
        IF cpf != "" THEN
			SET	variavel = CONCAT(variavel, " AND usuario_cpf = ", cpf);
		END IF;
        
        IF email != "" THEN
			SET	variavel = CONCAT(variavel, " AND usuario_email = ", email);
        END IF;
        
        IF matricula != "" THEN
			SET	variaveL = CONCAT(variavel, " AND usuario_matricula = ", matricula);
        END IF;
        
        IF nivel != "" THEN
			SET	variavel = CONCAT(variavel, " AND usuario_nivel = ", nivel);
        END IF;
        
        IF st != "" THEN
			SET	variavel = CONCAT(variavel, " AND usuario_status = ", st);
        END IF;
        
        SELECT usuario_id AS ID, 
			usuario_nome AS Nome,
			usuario_cpf AS CPF,
			usuario_email AS 'e-mail',
			usuario_matricula AS Matrícula,
			usuario_nivel AS 'Nível de acesso',
			usuario_status AS 'Status'
		FROM usuarios 
		HAVING (SELECT variavel);
    END $
DELIMITER ;

CALL usuario("", "", "", "", "", "", "")