# Schema Creation and Modification

### CREATE

As mentioned in Basics, the term database is mapped to schema in Polypheny. To select a database, the following command can be used:

use database

If the database does not already exist, it gets created automatically.

Similarly, to generate a collection the following command can be used:

db.createCollection( <name>, <options> )

If the collection already exists this command is a no-op.

To generate a new view the following syntax is used, if the collection does not exist an error is thrown:

db.createView( <view>, <source>, <pipeline>, <options> )

### DROP

The following command removes the complete database, so it should be used with care:

db.dropDatabase()

To drop a specific collection and all its content the following command is used:

db.collection.drop( <options> )

### RENAME

To rename a collection use the following command:

db.collection.renameCollection( <target>, <dropTarget> )