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This article is about how to query the top 50% of data in mysql. The editor thinks it is very practical, so share it with you as a reference and follow the editor to have a look.

Experimental environment:

Create table t (c int)

Insert into t values

(15), (7), (9), (10), (7), (8), (20), (16), (9), (19)

(14), (10), (11), (10), (10), (12), (7), (10), (7), (9)

Commit

The number of c equals 10, 7, and 9 is 11, more than half of them.

More than half of the item information.

General way, do not rely on the specific database.

Select t5. Recall journal t6. If null (round (t5. Sumtotalpact t6. Total2), 0) result from (

Select t3.rn ifnull t3.totalist t3.c ifnull (t4.total.0))

Select

T1.*

(

Select count (case when t2.total > t1.total then 1 when t2.total=t1.total and t2.ct1.total then 1 when t2.total=t1.total and t2.c t4.rn)

Group by t3.rn,t3.total,t3.c

) T5

Left join (

Select count (*) total from t

) T6 on (1x 1)

Where ifnull (round (t5.sumtotalswap t6.totaltal2), 0)

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