SQL how to count all rows up to a max value
I am having trou开发者_运维百科ble counting the number of rows until it reaches a certain PK.
My PK is called id and I want to count all rows until i reach a specified id
I have tried using this query but it doesn't work probably becuase I am using a MySQL table
select max(count(*)) from news where id=18 group by id
I get this error
Invalid use of group function
select count(*) from news where id<=18
I would use the following:
select count(id) from news where id <= 18
This will be more efficient as you are only returning one column in a row as opposed to all of them.
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