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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 Tag Sets.


You must apply readPref() to the cursor before retrieving any documents from the database.