Read the sqlnet trace files

While troubleshooting sqlnet  issue a week back and we used very same article  to read trace files. It was very useful.

Open Oracle Database with Delay Option

Found an interesting event, that helps to open the database with delay option. The event db_open_begin delay (opening database with delay)  is undocumented event ( read unsupported )

PostgreSQL Basic & Required Parameter Setting

    PostgreSQL works even if you start using it with the default settings without changing the parameter settings, but there may be various problems later, especially the default of performance-related parameters.

Is it possible to view database performance information without DBA privilege in Oracle 11g?

 

The DBA can grant you SELECT privileges to the V$ performance views. It's good for instance tuning, but not as effective as SQL Trace or ADVISOR privilege for query tuning.

How to kill own Oracle SQL sessions without DBA privileges?

 

To successfully run an ALTER SYSTEM command, you don't need to be the DBA, but you do need the ALTER SYSTEM privilege to be granted to you (or to the "user" owning the application through which you connect to the database - which may be different from "you" as the "user" ).

Postgres Frequently used commands - CHEAT SHEET

 \db- List all tablespaces

\dn- List all schemas

Postgresql Database Starts with 100% CPU processes ?

If you have a problem with PostgreSQL, it starts some processes that consume lots of resources. You kill those processes but they will restart after a few minutes.

Later you check the /var/log but there is nothing about this. What does that mean?😟

Oracle : Move indexes to another tablespace

 

Postgres High Availability Terms

 What is High Availability?

It is the amount of time that a service is available and is usually defined by the business.

Oracle Session Kill Script - Session Management

 

Possible ways to recover space from deleted rows with insufficient disk space remaining for full vacuum

 A recent scenario,

We had a single table with about 50M records that use around 80gb of space. Application recently deleted older records which was no longer needed reducing the Number of records to 30M.

What to do if listener log has grown too big in size

 

RMAN Backup Validate

 Sometimes RMAN backup files might get corrupted. Sometimes disk block corruption might happen. So it is better we do validate the database backups more frequently in order to make sure it is recoverable.

Oracle Blocksize selection

I had gone through Oracle documents, forums, and other websites but could not get a clear picture of what blocksize to choose for my environment where 64 bit OLTP databases are running. I came across the following websites that give practical and more useful information about Oracle Block size selection.

http://www.ixora.com.au/tips/buffered_block_size.htm

http://www.nextre.it/oracledocs/blocksize.html

The Surprising Impact of Medium-Size Texts on PostgreSQL Performance

 This is a great explanation of Postgres toast internals for anyone who doesn't know about them 

https://hakibenita.com/sql-medium-text-performance