framework/resources/Functional/joins/nulleqjoin/nullEqJoin_22.q

SELECT t1.col_int , t2.col_int 
FROM typeall_l t1, typeall_r t2 
WHERE t1.col_int = t2.col_int 
AND ((t1.col_chr = t2.col_chr) 
OR (t1.col_chr IS NULL AND t2.col_chr IS NULL));