How can I add a boolean column to a
SELECT
WHERE
OR
t
+----+---+---+
| id | a | b |
+----+---+---+
| 1 | 2 | 3 |
| 2 | 3 | 2 |
| 3 | 5 | 2 |
+----+---+---+
SELECT * FROM t WHERE a<b OR b+1=a;
+----+---+---+
| id | a | b |
+----+---+---+
| 1 | 2 | 3 |
| 2 | 3 | 2 |
+----+---+---+
cond
+----+---+---+------+
| id | a | b | cond |
+----+---+---+------+
| 1 | 2 | 3 | 1 |
| 2 | 3 | 2 | 0 |
+----+---+---+------+
This should do it
SELECT id, a, b, IF(a<b, 1,0) as cond
FROM t
WHERE a<b OR b+1=a;