oracle – Page 7 – DBA Notes

Oracle SQL

Finding Empty Tablespaces in Oracle

I’m given a task to find the empty tablespaces.I’ve checked dev server and majority of the tables’ stats were locked.This solution takes time but works.…

Linux performance SQL

Understanding IOPS vs. throughput

Bulent Soylu January 9, 2023 linux oracle performance

Input/output operations per second (IOPS) and data throughput are two popular performance characteristics of any storage system. In the early days of computer technology, when…

Oracle Postgres SQL

Selectivity vs Cardinality

Bulent Soylu December 19, 2022 oracle performance SQL

What is selectivity? Selectivity is the estimated proportion of the rows that will return from our query based on the total rows of that table.…

Oracle

Enable or Disable Table Locks in Oracle Database

Bulent Soylu August 28, 2022 oracle Oracle 11g table_lock

Table Locks are an important part of Oracle Working Mechanism as they provide security from unwanted deletion or modification of table’s data which can sometimes…

Oracle

Column Histograms in Oracle 11g

Bulent Soylu August 17, 2022 frequency histograms height-balanced histograms histograms oracle performance

Data skew in a column can make it difficult for the optimizer to accurately estimate the cardinality of an operation. Without a histogram it will…

Oracle

Oracle Text Index

Bulent Soylu August 16, 2022 CTXCAT CTXRULE Indexes oracle Oracle Text Oracle Text Index preferences

With Oracle text indexes (or Domain index), we can index text documents and search it based on contents using text patterns with specialized text query operators. Oracle…

Oracle

Export Import statistics with dbms_stats in Oracle

Bulent Soylu March 14, 2022 DBMS_STATS oracle performance

You can use the Oracle dbms_stats and export utilities to migrate schema statistics from your PROD instance to your TEST instance, so that your developers…

Oracle

Oracle Version Numbers

Bulent Soylu March 14, 2022 oracle

Something that always comes up when discussing Oracle versions is that I am not always sure which number is the Major Database Release and which is the Database…