Exists or in which is better

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Please log in or register to answer this question. In IN clause, first sub query runs and the output is used as input for outer query.

In Exists clause, first the main query runs and take one row and check it in the sub query as input for the sub query in where clause.

Related questions. What is the difference between delete and truncate in SQL? SQL is not case-sensitive. Generally, SQL keywords are written in uppercase. Attention reader! We can list values directly or we want to provide a query result to the IN operator. Here ColumnNameX is matched with every value value1, value2,… in the list.

Exists Operator in SQL : If the argument sub-query is non-empty, exists construct returns the value true, otherwise false. To check whether a row is returned through this sub-query or not, it is used.

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