MySQL 8.0

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CREATE table Audit 
(id INT,
 auditName VARCHAR(50));

INSERT INTO Audit VALUES
(1,'test'),
(2,'fooTest'),
(3,'barTest');

CREATE table AuditStatus
(id INT,
 auditId INT,
 status VARCHAR(50));
 
INSERT INTO AuditStatus VALUES
(11,1,'started'),
(12,1,'completed'),
(13,2,'started');
 SELECT * 
    FROM AuditStatus s 
   WHERE s.status != 'completed' 


id
auditId
status


11
1
started

13
2
started


SELECT * 
  FROM Audit a 
  WHERE NOT EXISTS (
           SELECT null 
              FROM AuditStatus s 
              WHERE a.id = s.auditId   
           AND s.status != 'completed' 
);


id
auditName


3
barTest


SELECT * 
  FROM Audit a 
  WHERE NOT EXISTS (
      SELECT s.auditId
        FROM AuditStatus s
       WHERE a.id = s.auditId AND s.status = 'completed'
);


id
auditName


2
fooTest

3
barTest