Shulou(Shulou.com)06/01 Report--

MongdoDB Instance-》Database-》Collection-》Document-》Field (key/value pair)

bin execute./ mongod startup & background startup

./ mongo goes into the mongoDB shell, many of which are commands like mysql show dbs(view database)

The requested URL/data/db/mongod.lock is not empty was not found on this server.

kill off mongod, delete mongod.lock, this file is similar to the cache file that records mongodb still started

create a database

use nameDB Create a database named nameDB and insert the data before viewing it via show dbs

delete database

use nameDB First enter database db.dropDatabase() Then delete the database (if you do not enter the corresponding database, the test database will be deleted by default)

Creating a collection in a database

db.createCollection("collectionName")

Delete a specified collection from a database

db.collectionName.drop()

Insert a document into a collection

db.collectionName.insert({"nameDocKey":"nameDocValue"}) Similar to Save.

query aggregate data

db.collectionName.find() query.pretty() query and format display db.collectionName.find({"key":"value"}); query specified document

modify a document

db.collectionName.update({"key":"value"},{"newKey":"value"},{upsert:true}) upsert=true If not present, insert db.collectionName.update({"key":"value"},{$set:{"oldKey":"newValue"}) Modify specified attributes

delete documents

db.collectionName.remove({}) Delete all documents in the collection without deleting the collection db.collectionName.list.remove({"key":"value"}) Delete specified document

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