Direct Path Insert &/vs Conventional Insert

Hi there, I couldn’t write anything for a while. Those days were busy. So I would talk to about direct path insert and conventional insert. Many people think that they are using “direct path insert” when used sqlldr utility but they are not. it is easy to confused batch insert and direct path insert. of

Oracle Table Compression Part1

Hi, I have been dealing with table compression a lot during my development period and I still do. I wanted to share some information about table information but I believe this will be a long explanation so I will write them in parts and this is part1. Table compression is a very useful feature of

Redo Log Switch Order

Hi, I always have the impression that redo log switch occurs in group number order but a small test showed me, I was wrong. As you know redo log is one of the most important part of a Oracle database. it almost protect everything! your data in memory, data file, your transaction etc.  whenever you

Timestamp Arithmetic and Well Known Mistakes

Hi, Lately, I started to see many developer uses timestamp types (like timestamp or timestamp with time zone) wrong especially in time arithmetic. So as a short reminder, adding and subtracting numbers to/from a DATE value will add/subtract number of days: Basically that is all if you use add and subtract of course we

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.

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.