MongoDb Add + delete field to table

MongoDB uses the update () and Save () methods to update the documents in the collection

Parameter description:

• Query: The search condition for update, similar to where in SQL update query.
• Update: Update object and some updated operators (such as $, $inc ... ) can also be understood as the SQL update query within the set after the
• upsert : Optional, this parameter means that if there is no record of update, insert objnew,true as INSERT, default is False, do not insert.
• multi : Optional, mongodb default is False, only update the first record found, if this parameter is true, will be found on the condition of a number of records update all.
• writeconcern : Optional, throws an exception level.

1. Add a field. Table represents the name of the sheet, adds a field type, an integer type, and a value of 1.

Db.getcollection (' article '). Update ({}, {$set: {type:numberint (' 1 ')}}, {multi:true})

2. Delete a field

Db.getcollection (' article '). Update ({},{$unset: {content: ""}},false, True)

Transferred from: https://www.cnblogs.com/crystaltu/p/6932377.html

MongoDb Add + delete field to table