cursor.isExhausted()
cursor.isExhausted()Important
mongosh Method
This is a
mongoshmethod. This is not the documentation forNode.jsor other programming language specific driver methods.In most cases,
mongoshmethods work the same way as the legacymongoshell methods. However, some legacy methods are unavailable inmongosh.For the legacy
mongoshell documentation, refer to the documentation for the corresponding MongoDB Server release:For MongoDB API drivers, refer to the language specific MongoDB driver documentation.
Returns: Boolean cursor.isExhausted()returnsfalseif documents remain in the current document batch read by the cursor. Otherwise, returnstrue.
Behavior
Tailable Cursors
You can use isExhausted() with a tailable cursor. A tailable cursor stays open even if
no documents remain in the current batch. Other cursors are
automatically closed when no documents remain.
Change Streams
You cannot use isExhausted() with change streams. Instead, to examine if:
documents remain in a change stream cursor, use
cursor.tryNext().a change stream cursor is closed, use
cursor.isClosed().
For a change stream example, see Watch Example.
Examples
This section contains examples that use a cursor to read documents from
a collection with temperature readings from a weather sensor. You'll see
examples of isExhausted().
Create the collection
Run:
db.sensor.insertMany( [ { _id: 0, temperature: 12 }, { _id: 1, temperature: 23 } ] )
Create a cursor variable
Create a cursor variable named sensorCursor that reads the
documents from the sensor collection:
var sensorCursor = db.sensor.find()
Count the number of documents in the cursor
Run:
sensorCursor.count()
The output is 2 because there are two documents in the
collection.
Return the first document from the cursor
Run:
sensorCursor.next()
Output:
{ _id: 0, temperature: 12 }
Examine the isExhausted() value
Run:
sensorCursor.isExhausted()
The output is false because there is a remaining document
in sensorCursor.
Return the next document from the cursor
Run:
sensorCursor.next()
Output:
{ _id: 1, temperature: 23 }
Attempt to return the next document from the cursor
Run:
sensorCursor.next()
There are no more documents and the example returns null.
Examine the isExhausted() value
Run:
sensorCursor.isExhausted()
There are no more documents and isExhausted() returns
true.