发布于 2015-09-14 14:49:09 | 99 次阅读 | 评论: 0 | 来源: 网络整理
Append the cursor.snapshot() method to a cursor to toggle the “snapshot” mode. This ensures that the query will not return a document multiple times, even if intervening write operations result in a move of the document due to the growth in document size.
警告
The snapshot() does not guarantee isolation from insertion or deletions.
The cursor.snapshot() traverses the index on the _id field. As such, snapshot() cannot be used with sort() or hint().
Queries with results of less than 1 megabyte are effectively implicitly snapshotted.