Help with MySQL query to select only records with specific value in column
I have following table:
+--------+-----------+--------+
| ID | Title | Stat |
+--------+-----------+--------+
| 1 | title a | 1 |
+--------+-----------+--------+
| 1 | title b | 0 |
+--------+-----------+--------+
| 2 | title c | 1 |
+--------+-----------+----开发者_运维知识库----+
| 2 | title d | 1 |
+--------+-----------+--------+
| 3 | title e | 0 |
+--------+-----------+--------+
| 3 | title f | 1 |
+--------+-----------+--------+
| 3 | title g | 1 |
+--------+-----------+--------+
I need to construct a query, where as a result only those records would be included where ALL values in column Stat meet certain condition.
For above table, how to formulate a query that would basically mean: show me records for only those ID's that have all the values in column Stat = 1 and would as a result produce following table?
+--------+-----------+--------+
| 2 | title c | 1 |
+--------+-----------+--------+
| 2 | title d | 1 |
+--------+-----------+--------+
Thanks.
Something like this?
SELECT
*
FROM table t
LEFT JOIN (
SELECT
MIN(Stat) AS Stat,
ID
FROM table
GROUP BY ID
) minstat ON t.ID = minstat.ID
WHERE minstat.Stat = 1;
Basically, the subquery computes the minimum stat per ID, whereas the outer query only selects the rows with the minimal stat equal to 1. If all rows need to satisfy a certain condition, insert a boolean expression in stead of Stat in the minimum.
Not sure if this is possible without a subquery.
This also works,
SELECT * FROM tablename t1
WHERE (
SELECT COUNT(*) FROM tablename t2
WHERE t1.ID = t2.ID AND t2.STAT = 0
) = 0
this query checks, is where a STAT with value 0 in records with same ID.
How about this:
select * from t where not (id in (select id from t where stat=0));
All 3 suggested solutions above work well, difference is only in the speed of execution. On a table where 3 records are found among approximately 7000 results are:
Martijn's: Showing rows 0 - 2 (3 total, Query took 0.0069 sec)
Alex's: Showing rows 0 - 2 (3 total, Query took 0.1162 sec)
Pavelasc's: Showing rows 0 - 2 (3 total, Query took 0.6160 sec)
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