SELECT
DB33,
Stream,
Coil,
MAX(Time) AS time,
`View`
FROM
result_video_szy
GROUP BY
DB33
order by NULLproblem description:
1.
2.query
3.order by NULL:mysqlsort
4.
SELECT
DB33,
Stream,
Coil,
MAX(Time) AS time,
`View`
FROM
result_video_szy
GROUP BY
DB33
order by NULLproblem description:
1.
2.query
3.order by NULL:mysqlsort
4.
create an index for db33?
DB33 create an index. About how much data is queried.
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