sql - Comparing value in a table vs count of rows in other table -

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i have 2 tables (primary key - unit_id) , b (primary key - unit_id)

i have value (eg :4 ) in table , has unit_id.

i have 4 rows in table b same unit id

i have write sql query check whether value in table matches count (rows) in table b same unit_id

you can use inner join , see how many values table in table b :

select a.unit_id table1 inner join table2 b on a.unit_id = b.unit_id

im assumin need , because @stanislavl pointed out, cant have more 1 unique unit_id in each table.


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