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- mongo Shell Methods >
- Cursor Methods >
- cursor.readPref()
cursor.readPref()¶
Definition¶
- cursor.readPref(mode, tagSet)¶
Append readPref() to a cursor to control how the client routes the query to members of the replica set.
Parameter Type Description mode string One of the following read preference modes: primary, primaryPreferred, secondary, secondaryPreferred, or nearest tagSet array Optional. A tag set used to specify custom read preference modes. For details, see 标签设置. 注解
You must apply readPref() to the cursor before retrieving any documents from the database.