MongoDB Update operation

In addition to the query criteria, you can use the modifier to update the document. 1. $inc > Db.tianyc03.find () {"_id": ObjectId ("50ea6b6f12729d90ce6e341b"), "name": "Xtt", "Age":}> db.tianyc03 . Update ({name: ' Xtt ', age:11},{' $inc ': {age:5}}) > Db.tianyc03.find () {"_id": ObjectId ("50ea6b6f12729d90ce6e341b") , "name": "Xtt", "Age":}# $inc You can also add columns. > Db.tianyc04.find () {"_id": ObjectId ("510c83ad13d7e50c2281b048"), "WC": 1}> db.tianyc04.update ({wc:1},{$inc: { SCORE:50}) > Db.tianyc04.find () {"_id": ObjectId ("510c83ad13d7e50c2281b048"), "score": +, "WC": 1}>2. $set is used to specify a value for a key that is created if the key does not exist. If you need to remove the key, use $unset. #新增加列sex > Db.tianyc03.update ({name: ' Xtt ', age:16},{$set: {sex: ' m '}}) > Db.tianyc03.find () {"_id": ObjectId (" 50ea6b6f12729d90ce6e341b ")," age ": +," name ":" Xtt "," Sex ":" M "} #修改列sex > Db.tianyc03.update ({name: ' Xtt ', age:16},{ $set: {sex: ' Male '}) > Db.tianyc03.find () {"_id": ObjectId ("50ea6b6f12729d90ce6e341b"), "age": +, "name": "Xtt", "se X ":" Male "} #改变列sex数据类型 > Db.tianyc03.update ({name: ' Xtt ', age:16},{$Set:{sex:1}) > Db.tianyc03.find () {"_id": ObjectId ("50ea6b6f12729d90ce6e341b"), "age": +, "name": "Xtt", "Sex": 1 } #删除列sex > Db.tianyc03.update ({name: ' Xtt ', age:16},{$unset: {sex:1}}) > Db.tianyc03.find () {"_id": ObjectId (" 50ea6b6f12729d90ce6e341b ")," age ": +," name ":" Xtt "} 3. $push used to increase the array. If you do not change the column, it will automatically increase. > Db.tianyc03.find () {"_id": ObjectId ("50ea6b6f12729d90ce6e341b"), "age": +, "name": "Xtt"}> db.tianyc03.update ({' name ': ' Xtt '},{$push: {companies: ' neu '} ') > Db.tianyc03.find () {"_id": ObjectId ("50ea6b6f12729d90ce6e341b"), " Age ": +," companies ": [" Neu "]," name ":" Xtt "}> db.tianyc03.update ({' name ': ' Xtt '},{$push: {companies: ' Alibaba '}}) & Gt  Db.tianyc03.find () {"_id": ObjectId ("50ea6b6f12729d90ce6e341b"), "age": +, "companies": ["Neu", "Alibaba"], "name": "Xtt"}4. $addToSet The #push operation does not check if the elements in the array are duplicates, you need to use $addtoset> db.tianyc03.update ({' name ': ' Xtt '},{$addToSet If you need to add the non-repeating data to the array: { Companies: ' Alibaba '}) > Db.tianyc03.find () {"_id": ObjectId ("50ea6b6f12729d90ce6e341b ")," age ": +," companies ": [" Neu "," Alibaba "," Alibaba "]," name ":" Xtt "}> db.tianyc03.update ({' Name ': ' Xtt '},{$addToSet: {companies: ' Congxing '}}) > Db.tianyc03.find () {"_id": ObjectId ("50ea6b6f12729d90ce6e341b"), "Age": +, "companies": ["Neu", "Alibaba", "Alibaba", "congxing"], "name": "Xtt"}> db.tianyc03.update ({' name ': ' XT T '},{$addToSet: {companies: ' Congxing '}}) > Db.tianyc03.find () {"_id": ObjectId ("50ea6b6f12729d90ce6e341b"), "age" : +, "companies": ["Neu", "Alibaba", "Alibaba", "congxing"], "name": "Xtt"}>5. $pop to remove data from an array by $pop. At this point the data is considered a queue. Using {$pop: {key:1}} will remove the element from the end of the queue, using {$pop: {key:-1}} to remove the element from the beginning of the queue. > db.tianyc03.update ({' name ': ' Xtt '},{$addToSet: {companies:[' C1 ', ' C2 ']}}) > Db.tianyc03.find () {"_id": ObjectId ("50ea6b6f12729d90ce6e341b"), "age": +, "companies": ["Neu", "Alibaba", "Alibaba", "congxing", ["C1", "C2"] ], "name": "Xtt"}> db.tianyc03.update ({' name ': ' Xtt '},{$pop: {companies:1}}) > Db.tianyc03.find () {"_id": ObjectId ("50ea6b6f12729d90ce6e341b"), "age": +, "companies": ["Neu", "Alibaba", "Alibaba", "congxing"], "name": "Xtt"}&gt ;> db.tianyc03.update ({' name ': ' Xtt '},{$pop: {companies:-1}}) > Db.tianyc03.find () {"_id": ObjectId (" 50ea6b6f12729d90ce6e341b ")," age ": +," companies ": [" Alibaba "," Alibaba "," congxing "]," name ":" Xtt "}>6. $pull you can use $pull to remove elements from an array in addition to $pop, you can match the element values to delete all the elements on the match. > db.tianyc03.update ({' name ': ' Xtt '},{$addToSet: {companies: ' Teletek '}}) > Db.tianyc03.find () {"_id": ObjectId ( "50ea6b6f12729d90ce6e341b"), "age": +, "companies": ["Alibaba", "Alibaba", "congxing", "Teletek"], "name": "Xtt"}&G T Db.tianyc03.update ({},{$pull: {companies: ' Congxing '}}) > Db.tianyc03.find () {"_id": ObjectId (" 50ea6b6f12729d90ce6e341b ")," age ": +," companies ": [" Alibaba "," Alibaba "," Teletek "]," name ":" Xtt "}> db.tianyc0 3.update ({},{$pull: {companies: ' Alibaba '}}) > Db.tianyc03.find () {"_id": ObjectId ("50ea6b6f12729d90ce6e341b"), " Age ": +," companies ":["Teletek"], "name": "Xtt"}> 

Transferred from: http://www.cnblogs.com/yuechaotian/archive/2013/02/04/2890266.html

MongoDB Update operation