Originally posted by karthickkuchanu r
For each value of outer query, the inner query is executed.
For example, The outer query table emp x (x is alias) has values 1000,2000,3000
Now, in the inner query, I am using the emp table, and there are 3 salary in the table ie 1000,2000,3000, so when the values of outer query are compared with the inner query values, then for all the values of outer query, the inner query will be executed.i.e. fthe value 1000 of outer query will be compared with all the values of inner query i.e. 1000,2000,3000, followed by same way for 2000,3000 of the outer query.
For more on correlated subqueries, check here
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