Sometimes Oracle Database Administrators needs to kill a sessions in Oracle Database. The best way to do it is to ALTER SYSTEM KILL SESSION statement. To use this statement we must provide SID and SERIAL# of the session we are going to kill.

Redo Log Files are crucial for recovery in case of instance failure. Today I will show a bunch of commands how to manage them in Oracle Database. You can find more details on architecture of Redo Log Files in previous post How to multiplex Redo Logs in Oracle

How to get procedure code in Oracle
Frequently we need to find the procedure code, without using any developers’ tools like SQL Developer or TOAD. The easiest way to get the code is to use USER_SOURCE or DBA_SOURCE views or DBMS_METADATA PL/SQL Package.

Database Administrators can see below message on some systems
ORA-0xxxx: Message xxxx not found; No message file for product=RDBMS, facility=ORA
Usually it just indicates that the environment was wrongly setup.

Oracle SQL*Plus has a neat feature called AUTOTRACE, which enables us to get execution plan and additional statics about the running SQL statement. The main difference between AUTOTRACE and EXPLAIN PLAN is that AUTOTRACE actually executes the SQL statement. AUTOTRACE can be a helpful tool in Oracle Developer or Oracle DBA hands to check performance of SQL statements.

ORA-01536: space quota exceeded for tablespace is a common error in Oracle Database.
It means that users is trying to use more space than the Database Administrator assigned to him. Quota is a maximum number of bytes that a user can allocate in particular tablespace. Implementing quotas in database is a reasonable approach because it prevents buggy or malicious code to fill the tablespace.

Sometimes Oracle Database Administrators receive some strange requests like dropping or truncating the same table in several schemas. Obviously we can do such requests manually, but it would be time consuming and very hard to automate. Instead of performing such requests manually we can use a handy script.

Let's start from some theory, "what is unix timestamp?".
The unix timestamp is the way to measure time as a running total number of seconds after Unix epoch. Unix epoch started at 1st, January 1970 00:00:00 UTC. The often asked question is how to convert Unix timestamp to Oracle date.

Checking Oracle version is quite often task. The simplest method is to login to sqlplus and query V$VERSION view.