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CREATE TABLE A
(
AInt int,
AChar char(1)
);
CREATE TABLE B
(
BInt int,
BChar char(1)
);
INSERT INTO A (AInt, AChar) VALUES
(1, 'a'),
(2, 'a'),
(3, 'a'),
(1, 'b'),
(2, 'b'),
(3, 'b');
INSERT INTO B (BInt, BChar) VALUES
(1, 'a'),
(2, 'b'),
(3, 'c');
SELECT A.*
FROM A
JOIN B
ON AInt = BInt AND AChar = BChar;
SELECT *
FROM A
WHERE AInt IN (
| AInt | AChar |
|---|---|
| 1 | a |
| 2 | b |
| AInt | AChar |
|---|---|
| 1 | a |
| 2 | a |
| 3 | a |
| 1 | b |
| 2 | b |
| 3 | b |