Answers for "how to get the elements that missing in other tables sql"

sql missing records from another table

-- Returns missing my_table1 ID in my_table2 
SELECT DISTINCT t1.* FROM my_table t1
LEFT OUTER JOIN my_table2 t2
ON t1.ID = t2.ID
WHERE t2.ID is null;
-- Or:
SELECT t1.* FROM my_table1 t1 WHERE NOT EXISTS 
   (SELECT ID FROM my_table2 t2 WHERE t2.ID = t1.ID);
-- Or:
SELECT t1.* FROM my_table1 t1 WHERE t1.ID NOT IN 
   (SELECT ID FROM my_table2 t2 WHERE t2.ID = t1.ID);

how to get the elements that missing in other tables sql

SELECT A.ABC_ID, A.VAL FROM A WHERE NOT EXISTS 
   (SELECT * FROM B WHERE B.ABC_ID = A.ABC_ID AND B.VAL = A.VAL)