Hi, While I was checking V$SQL_PLAN view for a whole different reason, I realized that some of the cursors has incredibly high child cursors. I started to dig and finally I find the problem. My customer have a few frequently fast refreshed materialized views. One of them is refreshed every 10 seconds (you might say
Performance
Is It Possible to Change SQL Statement in the Database?
YES! Hi, today I want to write about something which has been asked for many times to me. Let’s say you have an application and it is running very poorly designed sql statements in your database and you are really bored having fights with development teams to ask a change about the sql. Well, in
Performance Gain of NOCOPY Parameters
Hi, Almost every Oracle database uses PLSQL codes like packages/procedures/functions etc. Complex systems with complex codes pass many arguments (parameters) many times between plsql objects. Passing parameters might be the most executed operations in a database. So how well do you pass your parameters? I assume you know about types of parameters like IN or
Native Compilation of a PLSQL Object
Hi, you’ve probably heard about “NATIVE” compilation about plsql objects. I wanted to demonstrate how it is work and whether it really does matter or not. By default Oracle compiles every plsql object as “INTERPRETED” which means, your plsql code transform into a intermediate form which interpreted every time when you run it. This part
Min/Max on same column
Hi, Let’s do a simple trick. You want to get min and max value of a column which is already indexed. As you know if you have an btree index on a column and try to get a Min or Max value then you will see an “Index Full Scan(Min/Max)” line in the execution plan.
Oracle 18c New feature Private Temporary Table
Hello, 18c introduced a new object called Private Temporary Table (I will call it PTT in this post). PTT is just another version of Global Temporary Table(GTT). The data is temporary and will be stored for a time. Data in temporary tables (both PTT and GTT) can be queried by the session which inserts the
Using Temp instead of Undo for GTTs
Hello everyone, with 12c we have a very nice new option; Temp Undo for GTTs (Global Temporary Tables). as you know temporary tables are used for storing temporary data. those tables data are stored in TEMP tablespace so they are not vital. Temporary tables can generates very little redo data so they are faster than