I had a pleasure to work with my colleagues from Oracle – Radosław Kut and Krzysztof Marciniak – at comparing the performance of In-Memory queries between Sparc M7, Intel® Xeon® X5670 and Intel® Xeon® E5-2699. You can find results of our findings in this presentation: https://www.oracle.com/webfolder/s/delivery_production/docs/FY16h1/doc17/DB12c-on-SPARC-M7.pdf Following their methodology I’d like to present appropriate results […]
Thanks to Oracle I had a possibility to test the new Sparc M7 with DAX coprocessors to boost In-Memory performance. You can read about it here and here My first thought was – how to check if and when the DAX coprocessors are being used? When you have a POC for Exadata, you want to […]
Let’s imagine the following situation – you have a table called EMPLOYEES_TMP which is a global temporary table with a variable number of rows – totally nondeterministic. And there is a query which runs very often to compare primary key values between this table and a remote one (which is basically the same but not […]
ORA-600 i IT School wspierają XXIV finał Wielkiej Orkiestry Świątecznej Pomocy. Nasze połączone siły dewelopersko-administratorskie przygotowały aplikację, za pomocą której będziecie mogli licytować złote serduszka oraz karty używając do tego celu komputerów lub urządzeń mobilnych. Wejdźcie i zalicytujcie na: https://licytacja.wosp.org.pl/. Cieszymy się, że możemy mierzyć wysoko razem z WOŚP. W tym roku pieniądze zostaną przeznaczone […]
At UKOUG Tech’15 (Super Sunday) there was a session called "12c: A Closer Look at the Multi-Process Multi-Threaded Model for Oracle on Linux/Unix" by Markus Flechtner. Since then I can’t stop thinking about the performance of this feature. Why Oracle decided to provide it? I did some tests regarding sort operations and threaded execution was […]
Let’s check, why PRAGMA UDF makes execution faster, then regular function. C function responsible for calling a PL/SQL code from SQL is called "plsql_run": Now let’s try to create a new HR session and create a simple function which will multiple values by 2: From other terminal I will connect to the HR session with […]
I’ve already showed you, how to escalate privileges in Oracle Databases. https://blog.ora-600.pl/2013/04/02/privilege-escalation-in-oracle-11gr2-part1/ https://blog.ora-600.pl/2014/12/23/simple-technics-of-privilege-escalation-part2-dbasysdba/ The question is – how to secure your database, if you don’t have EE or possibility to buy Oracle Database Vault or Oracle Advanced Security. Well – there’s always a DBA creativity 😉 For example – if you want to secure the […]
I było tak, że 31 dnia miesiąca sierpnia roku 2015, spotkali się entuzjaści Wyroczni w posiadłości AVIVA. I było tak, że dzierżąc kufle – po brzegi browarem wypełnione – zasiadło wielu aby posłuchać kilku, którzy chcieli się przemyśleniami swoimi podzielić. I stało się tak, że admin przepijał do dewelopera a deweloper do admina i pospołu dyskusja toczyła się wartka a […]
I’ve started the project called RICO – the tool, written in C++ for last resort data recovery. It can be used to extract data from corrupted datafiles and dump them in the form of text files. It is in the early development stage right now and the functionalities are narrowed to: Dump regular and partitioned […]