Αποτελέσματα Αναζήτησης
28 Ιουν 2013 · This variant based on recursive subquery factoring feature, introduced in Oracle 11g R2. with recursion_view(base, parent_id, child_id, qty) as ( -- first step, get rows to start with select parent_id base, parent_id, child_id, qty from md_boms union all -- subsequent steps select -- retain base value from previous level previous_level.base ...
This articles gives an overview of how to query hierarchical data in Oracle databases using recursive subquery factoring. This functionality was introduced in Oracle 11g Release 2, giving an alternative to the method of performing hierarchical queries from previous versions .
Using recursive with you can choose any columns in your query to mark a "loop". This allows you to stop processing before you get back to the same row. For example, you can cycle on department_id.
The NOCYCLE parameter instructs Oracle Database to return rows from a query even if a CONNECT BY loop exists in the data. Use this parameter along with the CONNECT_BY_ISCYCLE pseudocolumn to see which rows contain the loop. Refer to CONNECT_BY_ISCYCLE Pseudocolumn for more information.
This articles gives an overview of how to query hierarchical data in Oracle databases using SQL. Setup. Basic Hierarchical Query. Cyclic Hierarchical Query. Related articles. Hierarchical Queries in Oracle (CONNECT BY) Hierarchical Queries in Oracle (Recursive WITH Clause)
Release 19. SQL Language Reference. SELECT. Purpose. Use a SELECT statement or subquery to retrieve data from one or more tables, object tables, views, object views, materialized views, analytic views, or hierarchies.
20 Φεβ 2019 · Oracle (Prior to 11g Release 2) – Hierarchical Queries. Up to Oracle 11g release 2, Oracle databases didn't support recursive WITH queries. In Oracle SQL these kinds of queries are called hierarchical queries and they have completely different syntax, but the idea is quite the same.
