Oracle RDBMS 11gR2 – goodbye Connect By or: the end of hierarchical querying...
Many years ago, Oracle basically set the standard in SQL. Whatever was Oracle SQL could be seen as the standard. This has never been absolutely true – ANSIÂ SQL was different from Oracle SQL. In some...
View ArticleOracle RDBMS 11gR2 – new style hierarchical querying using Recursive Subquery...
Oracle Database 11g Release 2 introduces the successor to the good old Connect By based hierarchical querying, called Recursive Subquery Factoring. The basics are described in a previous article:...
View ArticleOracle 11gR2 – alternative for CONNECT_BY_ISLEAF function for Recursive...
On our blog, we have been discussing the new hierarchical query functionality in Oracle Database 11g Release 2, using Recursive Suquery Factoring. Instead of using CONNECT BY and its close associates...
View ArticleAnti-Search patterns – SQL to look for what is NOT there – Part Two
It is a strange thing really: querying the database to find missing data. Queries usually report on what is there. Not the queries in this article (and its prequel): they report on what is not there....
View ArticleThe Knight's Challenge – Recursive SQL Queries make a move on the Chess board
In my quest to position ‘connect by’ (and its 11g successor, Recursive Subquery) as mechanism for recursive queries rather than just an hierarchical query facility, I stumbled across a simple, fairly...
View ArticleFactorial in Oracle SQL – using both new Recursive Subquery and classic...
I regularly teach a masterclass on Oracle SQL. One of the topics I explore in depth is the use of the CONNECT BY query style to perform not just hierarchical queries but also networking or even generic...
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