MongoDB

1. MongoDB InstallationFirst download MongoDB, official website address; Http://www.mongodb.org/downloadsCurl-o http://downloads.mongodb.org/linux/mongodb-linux-x86_64-2.6.1.tgzUnzipTAR-ZXVF mongodb-linux-x86_64-2.6.1.tgzNew CatalogMkdir-p mongodbcp-

No write has been do on this connectionThe problem arose for several days. Dozens of times a day in the log no write has beendo on this connection,So study for several days.The operation of the program is to throw GetLastError when a problem

One: Create new folders and files:MONGO installed in F:\DataBase\MongoDB_2.6, create a new folder in this directory:F:\DataBase\MongoDB_2.6\data\dbF:\DataBase\MongoDB_2.6\data\logF:\DataBase\MongoDB_2.6\data\log\MongoDB.logTwo: Create a databaseJump

1. Storage typeThe MongoDB document is similar to JSON, but not full JSON. There are only six types of JSON: null, BOOL, number, string, array, object. But MONGO's documents also extend several types, such as date types, integers, and floating-point

When a Select statement grows to an infinite number, it uses a common "select * from table order by…" statement ..." Statement. Figure 2-21 shows the processing process of the statement between each component in the database. Each step represents: (1

The concepts related to DB2 are confusing. It is not a system, but it will be placed here. With these basic concepts of DB2, we can find the context for subsequent learning. Search sequence of environment variables: When DB2 is started, it starts to

Will be installed or uninstalled. There are not many detailed installation instructions. I think this is well written.Preparation. 1. Use ps-ef | grep db2 to find the db2 installation directory 2./db2level to find the DB2 installation version and

Some environmental variables and configuration information of DB2 are very important, although they do not change frequently. However, this information is very important when the database is restored. Therefore, it is necessary to back up data. In

Integration is endless. The IT environment is constantly changing. New applications are constantly emerging online. Changes to the release level of packaged applications will generate a chain reaction to the entire infrastructure. People always try

Create an instance # Cd/opt/IBM/db2/v9.7/instance #./Db2icrt-p 50004-u db2inst4 db2inst4 Database creation $ Db2 create db payment on/home/db2inst4 using codeset GBK territory CN Check backup files $ Db2ckbkp-h PAYMENT.0.db2inst2. node1_.catn1_.20

MongoDB profiler is a good tool for analyzing slow queries when the database is running. By default, slow query means that the query time is more than Ms. This value can be modified. Let's take a look at how to use it. Step 1 log on to the primary

Help command: Show dbs: displays the Database List Use : Switch the current database, which means the same as in the MS-SQL MongoDB does not have commands for creating databases, but similar commands are available. For example, if you want to create

For example, each document in the SET has a field indicating the epoch seconds. The task is to subtract the value of this field from the epoch of the current time. If the difference exceeds 300 seconds, it is queried. Let's take a look at the

A part of the record related to permission management. Instance-level permissions: SYSADM has the highest management permission, which is usually used by DBAs. SYSCTRL has the highest system control permission and has all SYSMAINT and SYSMON

Runstats can compare two different methods for the same thing to find out who is better. We only need to provide two different methods, and runstats is responsible for the rest of the tasks. Runstats is only a measurement of three elements: 1. Time

I didn't pay attention to using JavaScript to manage MongoDB in the past, but this is a useful function. In particular, you can write some scheduled scripts, regularly check the database, and perform some management tasks. 1. mongo shell can

A few days ago, I summarized the mongodb installation entry and explained in detail the basic operations for adding, deleting, modifying, and querying. Today I will summarize more advanced operations, aggregation, and cursors for mongodb. I.

To port Oracle database users to DB2, IBM will add the range partition (range partitioning) feature in DB2, codenamed Viper, it is expected that the new version of DB2 will be tested in mid-December August this year or mid-December September. In

In the database management system (DBMS) field, the term "concurrency" is used to indicate the ability of more than one application to access the same data from the user's perspective. One of the main advantages of DBMS is that it can share data

IntroductionBy configuring the application server/IDE for the database, you can create a JDBC connection on the WebLogic application server, JBoss application server, or JDeveloper IDE, and use the connection to the DB2 database in the J2EE