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How to disable a SQL Plan Directive permanently

By Franck Pachot . In 12c you will see a lot of SQL Plan Directives. Some are useful to get better execution plans, but some will trigger too much Adaptive Dynamic Sampling and that can become a big overhead,(…)

SAP HANA SQL scripting optimization: the CE Functions

In SAP HANA, you have two possibilities to create the Calculated Views: Using the graphical method Using the scripting method with CE functions In this blog, I will demonstrate that CE Functions can improve performances from a Calculated(…)

SQL Server 2016 CTP2 : first thoughts about tempdb database

In my first blog about SQL Server 2016, I noticed during the SQL Server installation process that we are able to configure the number of files for tempdb. This is surely a great improvement(…)

Convert a snapshot standby to a new database

By Franck Pachot . A snapshot standby database is a nice solution when you want a temporary copy of the primary where you can do whatever you want (test a bug fix for example) and then convert it back(…)

SQL Server 2016 CTP2 is out!

As announced by Satya Nadella at the Microsoft Ignite keynote in Chicago, SQL Server 2016 CTP2 is finally out and it follows a previous private CTP. This CTP will provide some(…)

12c Dynamic Sampling and Standard Edition

By Franck Pachot . 12c is coming with more dynamic sampling, now called dynamic statistics and using the new Adaptive Dynamic Sampling algorithm. The goal is to have better estimations and better estimations gives better execution plans. However, this(…)

How to import SQL Plan Directives

By Franck Pachot . Today I’ve presented SQL Plan Directives at the SOUG Romandie event. I had a question about the import/export of directives by Data Pump. The idea is that a lot of testing has been done on(…)

DBA_SQL_PLAN_DIRECTIVE.LAST_USED

By Franck Pachot . If you have read Matching SQL Plan Directives and queries using it then you know how to use the ‘+metrics’ format of dbms_xplan. 21:49:54 SQL> explain plan for select distinct * from DEMO_TABLE where a=0(…)

What that in-memory term is about, and what not

Everybody is talking about in-memory databases these days. And everybody is talking about columnar store for sets of data because this can be a benefit for analytic queries. And a lot of people start mixing these terms not realizing that(…)

Alfresco: video thumbnails and transformations

Alfresco support, by default, the preview in your browser of some video formats like mp4 but doesn’t support some others like mkv, avi or wmv. Even if Google Chrome can read mkv files for example, if you try to use(…)