Which one is more efficient to use union or in?

I have always thought that in is more efficient, but this time I was a bit confused.

SELECT * FROM runinfo WHERE status in (0,2,1,3,4,7,9,10);　　

The efficiency of this query is often more than 1 second.

mysql> SELECT * FROM runinfo WHERE status in (0,2,1,3,4,7,9,10);

106 rows in set (1.20 sec)

After replacing it with the following writing method,

SELECT * FROM runinfo WHERE status = 0
union
SELECT * FROM runinfo WHERE status = 1
union
SELECT * FROM runinfo WHERE status = 2
union
SELECT * FROM runinfo WHERE status = 3
union
SELECT * FROM runinfo WHERE status = 4
union
SELECT * FROM runinfo WHERE status = 7
union
SELECT * FROM runinfo WHERE status = 9
union
SELECT * FROM runinfo WHERE status = 10　　

is very efficient promote.

mysql>
108 rows in set (0.02 sec)

I can’t tell you the specific reason. The status field is indexed and there will be some updates to this field.

Make a record first, and then figure it out later.

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