-- MCOL-1155
-- I can work around with colum1 is not null and column2 is null... 
-- but should it work with NOT (column1 <=> column2)? Here's an example.

SELECT * from cs1;
SELECT * from cs2;
SELECT * FROM cs1 JOIN cs2 USING(id,timestamp_);

SELECT * FROM cs1 JOIN cs2 USING(id,timestamp_) WHERE cs1.numeric_val <=> cs2.numeric_val;

SELECT * FROM cs1 JOIN cs2 USING(id,timestamp_) WHERE NOT (cs1.numeric_val = cs2.numeric_val);

SELECT * FROM cs1 JOIN cs2 USING(id,timestamp_) WHERE NOT (cs1.numeric_val <=> cs2.numeric_val);

SELECT * FROM cs1 JOIN cs2 USING(id,timestamp_) WHERE cs1.id <=> cs2.id;
SELECT * FROM cs1 JOIN cs2 USING(id,timestamp_) WHERE NOT (cs1.id <=> cs2.id);

SELECT * FROM cs1 JOIN cs2 USING(id) WHERE cs1.id <=> cs2.id;
SELECT * FROM cs1 JOIN cs2 USING(id) WHERE NOT (cs1.id <=> cs2.id);

SELECT * FROM cs1 JOIN cs2 USING(timestamp_) WHERE cs1.id <=> cs2.id;
SELECT * FROM cs1 JOIN cs2 USING(timestamp_) WHERE NOT (cs1.id <=> cs2.id);
