ORA-01100: database already mounted

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ORA-01100: database already mounted..

Answer / harbai computer education

ORA-01100: database already mounted

First off, what Oracle calls a "database" is generally different than what most other database products call a "database". A "database" in MySQL or SQL Server is much closer to what Oracle calls a "schema" which is the set of objects owned by a particular user. In Oracle, you would generally only have one database per server (a large server might have a handful of databases on it) where each database has many different schemas. If you are using the express edition of Oracle, you are only allowed to have 1 database per server. If you are connected to Oracle via SQL Developer, that indicates that you already have the Oracle database created.

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ORA-01100: database already mounted..

Answer / guest

Cause: A database is already mounted in this instance.

Action: none

Please add more information about this Error

Is This Answer Correct ?    13 Yes 16 No

ORA-01100: database already mounted..

Answer / amit

i think "database already mounted" means that

oracle instance is associated with your current database (
which ever you have database name (name may be "xe") )

so your new database in not creating because that instance
is engaged with your older database ,

ACTION - edit the pfile ( it is the file to create new
instance parameter) so that new instance will be created

now you can write the create database statement

Is This Answer Correct ?    19 Yes 29 No

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