V$SqlStats vs V$SqlStats_Plan_Hash, different columns?

Hi there, V$SQLSTATSis a beautiful view for information about sql statements. you might say v$sql has that information too which is correct but V$SQLSTATSis much more faster than v$sql and keeps data about sql statements for a longer time than v$sql. https://docs.oracle.com/en/database/oracle/oracle-database/19/refrn/V-SQLSTATS.html However, the V$SQLSTATS view differs from V$SQL and V$SQLAREA in that it is faster, more scalable, and has a

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

Oracle Join Methods

Hi, Actually I won’t explain anything today. I will just share a video by Chris Saxon who is also from askTom team. Great guy, you should also follow him. So he made a great, so simple and explanatory video that I have ever seen. Many thanks to Chris. Please watch.

Code Base Access Control & Invoker’s Right

Hi, So you might have already used some “invoker’s right” functions. As you know when you create a procedure/package/function and grant execute on them to other users, whenever other user run those codes, they will run with your privilege.  Sometimes you might need those objects to run with “invoker’s right”. that way you make sure

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

What is the Max Size of an Oracle Database?

Hi, sometimes I search for “what is the biggest” or “what is the highest” of things and I just realized that I never checked for the max size of an Oracle Database. so based on the limitations ( https://docs.oracle.com/en/database/oracle/oracle-database/19/refrn/physical-database-limits.html#GUID-939CB455-783E-458A-A2E8-81172B990FE9 ) and using default settings; default tablespace type is “smallfile” which means a datafile can contain

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.