MongoCursor::snapshot

(PECL mongo >=0.9.4)

MongoCursor::snapshot — Use snapshot mode for the query

说明

public MongoCursor::snapshot ( void ) : MongoCursor

Use snapshot mode for the query. Snapshot mode ensures that a document will not be returned more than once because an intervening write operation results in a move of the document. Documents inserted or deleted during the lifetime of the cursor may or may not be returned, irrespective of snapshot mode.

Queries with short responses (less than 1MB) are always effectively snapshotted.

Snapshot mode may not be used with sorting, explicit hints, or queries on sharded collections.

参数

此函数没有参数。

返回值

Returns this cursor.

错误／异常

Throws MongoCursorException if this cursor has started iterating.

参见

MongoDB core docs on » $snapshot operator.

相关文章
php dbx 函数 sort a result from a dbx query by a custom sort functionphp ingres 函数 escape special characters for use in a queryphp sqlite 函数 register an aggregating udf for use in sql statementsphp sqlite 函数 escapes a string for use as a query parameterphp trader 函数 set compatibility modephp mongocursor adds a top level key/value pair to a queryphp mongocursor counts the number of results for this queryphp mongocursor execute the queryphp mongocursor return an explanation of the query often useful for optimization and debuggingphp mongocursor sets the fields for a queryphp mongocursor get the read preference for this queryphp mongocursor gives the database a hint about the queryphp mongocursor sets a server side timeout for this queryphp mongocursor if this query should fetch partial results from mongos if a shard is downphp mongocursor set the read preference for this queryphp mongocursor sets whether this query can be done on a secondary deprecated php mongocursor use snapshot mode for the queryphp mongocursor sets a client side timeout for this queryphp mysqli stmt reads the next result from a multiple queryphp rarexception check whether error handling with exceptions is in use
关注编程学问公众号