WHY DO WE USE WITH clause in SQL?

Question

The SQL WITH clause is good when used with complex SQL statements rather than simple ones. It also allows you to break down complex SQL queries into smaller ones which make it easy for debugging and processing the complex queries. The SQL WITH clause is basically a drop-in replacement to the normal sub-query. 13 авг. 2021 г.

Why do we use with clause?

WITH clause allows us to give a subquery block a name that can be used in multiple places within the main SELECT, INSERT, DELETE or UPDATE SQL query. The name assigned to the subquery is treated as though it was an inline view or a table. It is very helpful when you need the same set of results data multiple times.

What is the advantage of WITH clause in Oracle?

The WITH clause may be processed as an inline view or resolved as a temporary table. The SQL WITH clause is very similar to the use of Global temporary tables. This technique is often used to improve query speed for complex subqueries and enables the Oracle optimizer to push the necessary predicates into the views.

Can we use with clause in SQL?

MySQL prior to version 8.0 doesn't support the WITH clause (CTE in SQL Server parlance; Subquery Factoring in Oracle), so you are left with using: TEMPORARY tables. DERIVED tables.

Can SQL query start with with?

Syntax. The syntax after the keyword with is the same as it is for create view : it starts with the query name, and optionally3 and in parenthesis the name of the columns it returns.

Expert · Answer

WITH clause allows us to give a subquery block a name that can be used in multiple places within the main SELECT, INSERT, DELETE or UPDATE SQL query. The name assigned to the subquery is treated as though it was an inline view or a table. It is very helpful when you need the same set of results data multiple times.

Expert · Answer

The WITH clause may be processed as an inline view or resolved as a temporary table. The SQL WITH clause is very similar to the use of Global temporary tables. This technique is often used to improve query speed for complex subqueries and enables the Oracle optimizer to push the necessary predicates into the views.

Expert · Answer

MySQL prior to version 8.0 doesn't support the WITH clause (CTE in SQL Server parlance; Subquery Factoring in Oracle), so you are left with using: TEMPORARY tables. DERIVED tables.

Expert · Answer

Syntax. The syntax after the keyword with is the same as it is for create view : it starts with the query name, and optionally3 and in parenthesis the name of the columns it returns.

WHY DO WE USE WITH clause in SQL?