Difference between revisions of "MongoDB Delete"

From mi-linux
Jump to navigationJump to search
Line 16: Line 16:
 
db.collectionName.remove(query_criteria) /* deletes all documents in a collection (use with care!) */
 
db.collectionName.remove(query_criteria) /* deletes all documents in a collection (use with care!) */
 
</pre>
 
</pre>
 +
 +
== Deleting a Collection ==
 +
 +
If you want to drop a collection completely, including any data held in it:
  
 
<pre style="color: red">
 
<pre style="color: red">
 
db.collectionName.drop() /* removes a collection completely (use with care!) */
 
db.collectionName.drop() /* removes a collection completely (use with care!) */
 
</pre>
 
</pre>
 +
  
 
== Delete Department 40 ==
 
== Delete Department 40 ==

Revision as of 11:14, 10 November 2016

Main Page >> MongoDB >>MongoDB Workbook >> Deleting a Document

Deleting a Document

At some stage you may want to delete a document from a collection. The format is:

db.collectionName.deleteOne(query_criteria) /* deletes the first document found that matches the query criteria */
db.collectionName.remove(query_criteria) /* deletes all documents found that matches the query criteria */
db.collectionName.remove(query_criteria) /* deletes all documents in a collection (use with care!) */

Deleting a Collection

If you want to drop a collection completely, including any data held in it:

db.collectionName.drop() /* removes a collection completely (use with care!) */


Delete Department 40

Department 40 has closed down:

db.deptCollection.deleteOne({deptno:40})

Note, if the query_criteria only returns one document, remove() and deleteOne() will have the same effect.


Check that the collection has gone:

db.deptCollection.find({deptno:40})

Next Step

This concludes the section on manipulating collections. Return to the Workbook.