mysql - SELECT SUM(CRC32(column)) LIMIT doesn't work -


i need checksum of specific column , specific number of rows using limit.

select sum(crc32(column)) table limit 0, 100;

but, value returned checksum of entire table. why happen? how can use limit checksum of specific number of rows?

the following works:

select sum(crc32(column)) table id > 0 , id < 101;

but don't want use method because of potential jumps in auto_increment value.

why happen?

limit gets applied after aggregate functions.

when used without group by, sum aggregates on whole table, leaving 1 record, falls under limit.

use this:

select  sum(crc32(column))    (         select  column            mytable         order                 id         limit   100         ) q

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