Oracle

when i have start oracle 12c database using sql developer but it shows initialization or shutdown in progress. any one help me come over the error???

SQL Developer is not used for starting a database; it is used for querying a database. “initialization or shutdown in progress” means that the database is not available for access. oracle-base.com/…/multitenant-startup-and-shutdown-cdb-and-pdb-12cr1.php has instructions for starting the container database and the pluggable databases. Try the FORCE option if normal startup fails.

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