how to query mongodb in java

Tags: value pos ble table ali relational fuzzy query float precisionExact query:sql:field= "Value"mongo:{"field": "Value"}---------------------------------Fuzzy query: Match on both sides Right match Left match Sql: Field= "%value%" Field= "Value%" Field= "%value" Mongo: {"Field":/value/}{"Field":/.value/}{"Field":/.value.*/}

(DIRECTION.ASC, "a", "B", "C"));(3) Different fields are sorted according to different List a ascending in descending order BStep three: Test class @Test public void Testlist () throws ParseException { pagemodelQuery condition is cname=zcy The Skip method is to skip the number of bars. And it's a one-way skip. Assuming that the collection is larger (such as a very large number of pages), skip will become slower, requiring many other processors (CPUs). This can aff

Dex introduces mongodb index and query analyzer dex. It is a MongoDB performance adjustment tool that compares MongoDB log files and index entries and provides index recommendations. Currently, you must provide a URI to connect to the database. Dex only recommends full indexes, not partial indexes. Windows platforms ar

and nosql As a nosql solution, MongoDB is easy to use. During my first in-depth research on nosql databases, I tried a lot of Java-based solutions and found out what column family is) what is the relationship between hadoop and hbase, and what is zookeeper very time-consuming. When I finally want to understand these problems, I realized that Cassandra, hbase, and other products are all very well-developed

GrammarThe syntax format for MongoDB query data is as follows:>db. Collection_name. Find() The Find () method displays all documents in an unstructured manner.If you need to read the data in an easy-to-read way, you can use the pretty () method, which has the following syntax:>db. Col. Find(). Pretty() The pretty () method displays all documents in a formatted manner.InstanceThe following exa

Tags: log script obj name instance method body code MonGrammarThe syntax format for MongoDB query data is as follows:>db. Collection_name.find ()The Find () method displays all documents in an unstructured manner.If you need to read the data in an easy-to-read way, you can use the pretty () method, which has the following syntax:>db.col.find (). Pretty ()The pretty () method displays all documents in a form

. driver. login server. create (strconn); // obtain the database test‑database db = server. getDatabase (dbName); Users users = new Users (); users. name = "test"; users. sex = "man"; // obtain the Users set. If the database does not exist, create a collection col = db. getCollection ("Users"); // execute the insert operation col. insert (Users );} Update Data Public void Update () {// create database link Login server = MongoDB. driver. logi

don't think so]. Many people are getting bored with Spring. Yes, Spring is ambitious. He almost wants to monopolize everything in Java. There is no way I can't do without Spring, so that I don't need to learn any other frameworks. I have learned a lot about Spring, such as Spring Security, Spring Integration, and Spring Batch... Without inventing the wheel, he has already provided many programming scenarios. I have used those scenarios to solve many

provided many programming scenarios. I have used those scenarios to solve many problems in my work and make my work very efficient. So I learned more about it. Spring Data Mongo encapsulates the mongodb java driver and provides the same programming style as SpringJDBC/Template. See: http://static.springsource.org/spring-data/data-mongodb/docs/current/api/org/spr

Tags: blog io os using java AR data problem spQuery the first document that meets the criteria (cannot be called a record for MONGO)Db. Collection_name.findone ({},{});Query for eligible documents and sort by specified criteria, skip the previous N1 documents, and return a list of up to N2 documentsSort skip limit three functions optionalDb. Collection_name.find ({},{}). The sort ({}). Skip (N1). Limit (N2)

"}}{"_ Id": ObjectId ("4dd7d214b2d55d5e1db1bb99"), "userId": "10010178", "userName": "Bill Tu8", "gender": "m8 ", "age": 8, "rank": [8, 8, 8], "interests ":{"Game": "game8", "ball": "ball8", "other": "nothing8 "}}{"_ Id": ObjectId ("4dd7d214b2d55d5e1db1bb9a"), "userId": "10010179", "userName": "Bill Tu9", "gender": "m9 ", "age": 9, "rank": [9, 9, 9], "interests ":{"Game": "game9", "ball": "ball9", "other": "nothing9 "}}{"_ Id": ObjectId ("4dd7d214b2d55d5e1db1bb9b"), "userId": "100101710", "user

Conclusion: 1, 200w data, reasonable use of the index case, a single stationid under 4w data. MongoDB Query and sorting performance ideal, no regular when the client can complete the query in 600ms+, qps300+. When there is a regular client can complete the query in 1300ms+, qps140+. 2,

be noted in the programDB Security Authentication for 2.2MONGODBIf you want to access the DB in collection (equivalent to the table in the relational database), you must pass security authentication to access, or the background will be reported that you did not pass security authentication.Secure authentication Java code returns true for pass, false indicates failure to operate byboolean auth =db.authenticate ("userName", "Password". ToCharArray ());

query information. A query must be defined first, also called a view), and then exposed. On the contrary, when using MongoDB, it is no different from most relational databases. You can query any information you want to see at runtime. For example, the following is an example of parking ticket that I implemented using

Introduction to MongoDB and addition, deletion, modification, and query I. Introduction MongoDB is written in C ++ and is an open source database system based on distributed file storage. MongoDB is designed to provide scalable, high-performance data storage solutions for WEB applications.

MongoDB official Java driver, save and read, the need is DBObject object, this is an interface, implementation put,get and other methods, similar to map, if we want to directly save ordinary Java objects to MongoDB, It needs to be converted into DBObject object first, or implement DBObject interface directly, it is qui

The MongoDB query document uses the Find () method. The Find () method displays all documents in an unstructured manner. Grammar Db.collection.find (query, projection) query: Optional, use the query operator to specify the query

Tags: mongodb slow query Analysis script1 IntroductionThis is used in the production environment of a MongoDB slow query log automatic collection of scripts, the original idea to write this script is to facilitate the collection of slow query logs and facilitate analysis. Be

MongoDB paging query method and Performance I have been a little busy recently. There are a lot of things to summarize. In fact, there should be four, five, and six Redis series... however, Redis in Action has not been completed yet. I will summarize it later. Otherwise, it will be too watery. Sorry, readers. Since the last time in Redis, it was a bit of an entry into Nosql products. This will change the di

(dataBaseName); Note: MongoDB is case-sensitive and must be noted in the program DB Security Authentication for 2.2MONGODB If you want to access the DB in collection (equivalent to the table in the relational database), you must pass security authentication to access, or the background will be reported that you did not pass security authentication. Secure authentication Java code returns true for pass, fal