you can consider using group by if it is the same table, but there is no good way to use different tables.
count (*) in PS:MYSQL is more efficient than count (field)
if there is no performance problem, you have no problem. Of course, just cache it.
and use explain to analyze
your subquery can also split 2 sql
`
select count (*), type as cnt fromo article where openID in = 43 group by type
select count (*) from diary where openId=43 and type='public'
`
then splice the returned array in the business.
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