SQL-query to find similar fields
In SQL, I have a table which have fields a_1,a_2,..., a_10
. What kind of开发者_如何学编程 query says if I have rows s,t
such that s.a_1=t.a_1 ,..., s.a_6=t.a_6
and for some j>6
we have s.a_i<>t.a_i
?
Join table to itself on the condition you supplied. Like:
select
a.ID
from
table as a join table as b
on a.a_1 = b.a_1 and ... and a.a_j <> b.a_j
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