cursor.isExhausted()
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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()returnstrueif the cursor is closed and there are no remaining objects in the batch.Use
isExhausted()to support iterating cursors that remain open even if there are no documents remaining in the current batch, such astailableorchange streamcursors.
Example
Consider the following while loop iterating through updates to
a change stream cursor:
watchCursor = db.collection.watch(); while (watchCursor.hasNext()) { watchCursor.next(); }
A change stream cursor can return an empty batch if no new data changes
have occured within a set period of time. This causes the while loop
to exit prematurely as cursor.hasNext() returns false
when it detects the empty batch. However, the change stream cursor
is still open and able to return more documents in the future.
Use cursor.isExhausted() to ensure the while loop only exits
when the cursor is closed and there are no documents remaining in the
batch:
watchCursor = db.collection.watch(); while (!watchCursor.isExhausted()) { if (watchCursor.hasNext()){ watchCursor.next(); } }