(PECL mongo >=0.9.4)
MongoCursor::snapshot — Use snapshot mode for the query
Use snapshot mode for the query. Snapshot mode assures no duplicates are returned, or objects missed, which were present at both the start and end of the query's execution (if an object is new during the query, or deleted during the query, it may or may not be returned, even with snapshot mode).
Note that short query responses (less than 1MB) are always effectively snapshotted.
Currently, snapshot mode may not be used with sorting or explicit hints.
This function has no parameters.
Returns this cursor.
Throws MongoCursorException if this cursor has started iterating.