Ed Chen Logic

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 »

How to Resolve ORA-00376: file cannot be read at this time

by Ed Chen
July 26, 2022July 25, 2022
2 Comments

ORA-00376 ORA-01110 Someone tried to perform a query, but it failed with ORA-00376 and ORA-01110. SQL> select first_name from employees where last_name = 'Chen'; select… Read More »

How to Resolve ORA-01113: file needs media recovery

by Ed Chen
July 25, 2022July 26, 2022

ORA-01113 ORA-01110 Tried to bring a data file online, but it failed with ORA-01113 and ORA-01110. SQL> alter database datafile '/u01/app/oracle/oradata/ORCLCDB/ORCLPDB/example01.dbf' online; alter database datafile… Read More »

How to Resolve ORA-00995: missing or invalid synonym identifier

by Ed Chen
July 22, 2022October 1, 2022

ORA-00995 ORA-00995 means that the synonym name you specified in the statement is either invalid or not found, you should make sure the synonym identifier… Read More »

Alter Table Add Column Oracle Examples

by Ed Chen
July 20, 2022October 1, 2022

ALTER TABLE ADD COLUMN In this post, I'll show you some practical examples of adding a column to table from the simplest to the complicated.… Read More »

How to Check User Creation Date in Oracle

by Ed Chen
July 18, 2022September 2, 2022

User Creation Date To check the creation date for a specific user, we can query ALL_USERS. SQL> alter session set nls_date_format='yyyy-mm-dd hh24:mi:ss'; Session altered. SQL>… Read More »

How to Check DataFile Creation Date

by Ed Chen
July 15, 2022June 17, 2022

Data File Creation Date To check the creation date time of data files, we should query V$DATAFILE, not DBA_DATA_FILES. First of all, we format the… Read More »

Oracle Default User

by Ed Chen
July 13, 2022July 28, 2022

Predefined and Customized Users Although we can look up the predefined accounts in the official documentation to make sure that we won't touch them in… Read More »

How to Resolve ORA-20200: Database Instance does not exist

by Ed Chen
July 11, 2022July 12, 2022

ORA-20200 When we ran a STATSPACK report, we got error ORA-20200. SQL> @?/rdbms/admin/spreport.sql ... ORA-20200: Database/Instance 356760607/1 does not exist in STATS$DATABASE_INSTANCE ORA-06512: at line… Read More »

Revoke Quota Unlimited on Tablespace from User

by Ed Chen
July 10, 2022October 2, 2022

Revoke Tablespace Quota In previous post, we have talked about how to set quota on tablespace for users. Now, let's see how to revert it.… Read More »