Ed Chen Logic

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

by Ed Chen
July 22, 2022July 29, 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 in Oracle by Examples

by Ed Chen
July 20, 2022July 29, 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

by Ed Chen
July 18, 2022June 17, 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 on Tablespace from User

by Ed Chen
July 10, 2022July 25, 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 »

Grant Quota on Tablespace to User

by Ed Chen
July 10, 2022July 25, 2022

Grant Tablespace Quota Since quota usage limitation is not an object privilege, we can't grant it like this: SQL> grant quota 100g on erpapp_tbs_01 to… Read More »

How to Build 19c RAC on Windows - 4 of 4 - Creating a RAC Database

by Ed Chen
July 9, 2022July 5, 2022

We click on Database Configuration Assistant (DBCA) in the menu to initiate the database creation process. We had better to restart both nodes to verify… Read More »

How to Build 19c RAC on Windows - 3 of 4 - Installing Database Software on All Nodes

by Ed Chen
July 8, 2022July 5, 2022

We click on "setup.exe" in DB home (i.e. C:\app\oracle\product\19.3.0\dbhome_1) to initiate the database software installation. Next, let's see how to create a RAC database 19c… Read More »