MongoDB Database Learning Notes

First, the MongoDB database of the increase and deletion check

Show databases
Show DBS//display database;

Show tables
Show collections//Chahi or set;

Use IMOOC//using or creating database Imooc;

Increase:
Use IMOOC
Db.imooc_collection.insert ({x:1})//To the collection name "Imooc_collection" Insert a single data "x:1";

Db.imooc_collection.insert ({x:2})//To the collection name "Imooc_collection" Insert a single data "X:2";
Db.imooc_collection.insert ({x:100,y:100,z:100})//Go to the collection name "Imooc_collection" to insert a multi-field single data;
Bulk INSERT Data "x:3-99" for (i=3;i<100;i++) Db.imooc_collection.insert ({x:i})//Toward the collection name "Imooc_collection";

By deleting:
Db.imooc_collection.remove ({c:2})//delete collection or table matching data (must pass parameter, otherwise error);
Db.imooc_collection.drop ()//delete collection or table;

Use IMOOC
Db.dropdatabase ()//delete database Imooc;

Change:
Db.imooc_collection.update ({x:1},{x:999})//Change the set name "Imooc_collection" in "X:1" to "x:999";
Db.imooc_collection.update ({z:100},{$set: {y:99}})//When looking for "z:100", only the Y field is updated as "y:99";
Db.imooc_collection.update ({y:100},{y:999},true)//When the data being found does not exist, insert a piece of data;
Db.imooc_collection.update ({c:1},{$set: {c:2}},false,true)//Bulk update of all matching data;

Note: MongoDB By default only updates the first data found, the purpose is to prevent update error operation;

Check:
Db.imooc_collection.find ()//query all data contents in the set name "Imooc_collection";
Db.imooc_collection.find (). Count ()//Statistics The number of all data contents in the set name "Imooc_collection";
Db.imooc_collection.find (). Skip (3)//query filter the first 3 data;
Db.imooc_collection.find (). Limit (10)//query limit displays only the first 10 data;
Db.imooc_collection.find (). Sort ({x:1})//query using "x" to sort;

Second, the index

Increase:
Db.collection.ensureIndex ()

By deleting:
Db.collection.dropIndex ("index name")

Change:

Check:
Db.collection.getIndexes ()

1._ID Index:

Use IMOOC
Db.table2.insert ({x:1})
Db.table2.getIndexes ()//_id index is a unique index that is automatically created by default when inserting data (the command is an index within the query collection);

2. Single Key index:

Db.table2.ensureIndex ({x:1})//Create a single-key index of "X:1", which is a single-key index when the query condition is a value;

3. Multi-key index:

Db.table2.insert ({x:[1,2,3,4,5]})//Insert an array, and then create an index that is a multi-key index;

4. Composite Index:

Db.table2.ensureIndex ({x:1,y:2})//The index created when the query condition is more than one is a composite index;

5. Expired index:

Db.table2.insert ({time:new Date ()})//Insert time: One piece of data for the current period;
Db.table2.ensureIndex ({time:1},{expireafterseconds:30})//Create an expired index with a key value of time and an expiration of 30;

Note: The data must be isodate or isodate array to be automatically deleted, every 60 seconds to perform the detection;

6. Full-Text indexing:

Db.table2.ensureIndex ({key: "text"})
Db.table2.ensureIndex ({key_1: "text", ke_2: "Text"})
Db.table2.ensureIndex ({"$**": "Text"})//Three ways to create a full-text index;

Db.table2.find ({$text: {$search: "AA"}})
Db.table2.find ({$text: {$search: "AA bb cc"}})
Db.table2.find ({$text: {$search: "AA Bb-cc"}})
Db.table2.find ({$text: {$search: "\" aa\ "\" Bb\ ""}})
Db.table2.find ({text:{$search: "AA bb"}},{score:{$meta: "Textscore"}}). sort ({score:{$meta: "Textscore"}})//Use full

Five ways to index the text;

Note: Full-text indexing can only specify one "text"; MongoDB temporarily does not support Chinese;

Index Important properties:
1. First name (name);
2. Uniqueness (unique);
3. sparsity (sparse);
4. Whether to delete periodically (expireafterseconds);

7. Location Index:

7.1 2d Index

7.2 2dsphere Index

Third, MongoDB security:

1. Open permission authentication;
2. Create a user;
3. Create user roles;

This article is from the "Square Hill" blog, please be sure to keep this source http://63638790.blog.51cto.com/513514/1650031

MongoDB Database Learning Notes