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Showing posts from January, 2015

January Edition of Oracle DW and Big Data Magazine

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Follow us onOracle Data Warehouse and Big Data Magazine JANUARY Edition for Customers + Partners

The latest edition of our monthly data warehouse and big data magazine for Oracle customers and partners is now available. It brings together all the most important announcements and videos taken from our data warehouse and big data Oracle product management blogs, Oracle press releases, videos posted on Oracle Media Network and Oracle Facebook pages. Click here to view the JANUARY Edition

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MATCH_RECOGNIZE and the Optimizer

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If you have already been working with the new 12c pattern matching feature you will have probably spotted some new keywords appearing in your explain plans. Essentially there are four new keywords that you need to be aware of:MATCH RECOGNIZESORTBUFFERDETERMINISTIC FINITE AUTOThe fist three bullet points are reasonably obvious (at least I hope they are!) but just incase…. the keywords MATCH RECOGNIZE refers to the row source for evaluating the match_recognize clause . The “SORT keyword means the row source sorts the data data before running it through the state machine to find the matches.  The last keyword is the most interesting and is linked to the use of “state machine”, as mentioned in the previous sentence. Its appearance or lack of appearance affects the performance of your pattern matching query. The importance of this keyword is based on the way that pattern matching is performed. To search for a pattern containing a specific set of events we build something called a “state-ma…