Data File

How to Resolve ORA-01135: file accessed for DML/query is offline

by Ed Chen
November 23, 2022October 25, 2022

ORA-01135 Some user reported an error ORA-01135 when querying the database. ORA-01135: file 1291 accessed for DML/query is offline ORA-01110: data file 1291: '/u01/app/oracle/oradata/orcl/users01.dbf' ORA-01135… Read More »

How to Resolve ORA-01157: cannot identify/lock data file

by Ed Chen
July 27, 2022October 1, 2022

ORA-01157 Saw error ORA-01157 when we tried to bring a tablespace online. SQL> alter tablespace example online; alter tablespace example online * ERROR at line… Read More »

What Can We See in a Normal Data File

by Ed Chen
October 30, 2019August 5, 2021

You might think that the content of a normal data file should be unrecognized binary text and we cannot really see it except using special… Read More »

How Max a Table Can Be

by Ed Chen
October 12, 2019August 27, 2021

Maximum Size Limit of a Table According to Oracle Logical Database Limits, tables can have at most 1000 columns and no limit on rows and… Read More »

How Max a Database Can Be

by Ed Chen
October 9, 2019June 10, 2022

Maximum Size Limit of a Database After knowing how big a data file can be and how big a tablespace can be in previous posts,… Read More »

How Max a Tablespace Can Be

by Ed Chen
October 5, 2019November 8, 2022

Tablespace Max Size Basically, at least one data file should be specified in the tablespace creation, thereafter we can add more data files to the… Read More »

How RMAN Restore Database from BackupSet

by Ed Chen
October 31, 2018October 20, 2022

In this post, I will show you how to restore a single-instance database from a backup set by RMAN. For RAC restoration, you may check… Read More »

How to Check Oracle Data Files Healthy

by Ed Chen
October 30, 2016October 2, 2019

Two ways that you can verify data files, one is using Oracle utility dbverify, the other is RMAN command.DbverifyWe can use dbv to check specific… Read More »

When Database is Not Consistent

by Ed Chen
October 2, 2016January 16, 2021

There are several different kinds of situation when you recover a database with inconsistent states among files. In the following, I have to assume that… Read More »

Alter Database Rename File

by Ed Chen
May 16, 2016October 15, 2022

Move Data File Offline Not like the new released statement ALTER DATABASE MOVE DATAFILE which can move data files online, the old-fashioned file renaming procedure… Read More »