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A hierarchical query is a type of SQL query that handles hierarchical model data. They are special cases of more general recursive fixpoint queries, which compute transitive closures. Unlike the Oracle extension described below, the recursive CTEs were designed with fixpoint semantics from the beginning. Without Common-table-expressions or a connected-by clause it is possible to achieve hierarchical queries with user-defined recursive functions. You can help by adding to it.
SELECT, INSERT, UPDATE, or DELETE statement. The RECURSIVE keyword is not usually needed after WITH in systems other than PostgreSQL. It’s possible, for example, to name the result using CREATE VIEW. Recursive Queries Using Common Table Expressions”.
The Hardware, Software and Heart of It. A Complete Guide to DB2 Universal Database. This page was last edited on 12 April 2018, at 18:21. This is the latest accepted revision, reviewed on 11 April 2018. For the computer program, see Europress.