Database Administrator

MongoDB 3.2 is faster MongoDB 3.2 is expected to be introduced in MongoDB World by the end of 2015. We believe this will benefit some attractive features. Most of these features are still evolving. Even though they are displayed, they may change

ORA-01555 Problem Analysis and Solution Today, my colleague sent me a problem, throwing a ORA-01555 error when running a Job, hope we can see what can be found from the database layer. The error log is as follows: Function: EntitySQLCursor:

Configure MongoDB3.04 cluster shards Most of the network is sharded by the ipv2.x cluster, so I wrote a 3.04 error.Because the company uses redundant storage of disk arrays, data backup is not considered as a simple partition storage data for

Example of myloader restoring MySQL database Mydumper is a lightweight third-party open-source tool for mysql database backup. The backup mode is logical backup. It supports multithreading, And the backup speed is much higher than the original

MyBatis calls the MySQL stored procedure and returns the result set. A result set is often returned in a stored procedure. MySQL directly uses select to return the result set. Oracle uses a cursor to return the result set. This is relatively

MySQL client server command summary, mysql client server MySQL contains the [client] and [mysqld] sections in the configuration file, and MySQL has its own client commands and server-side commands. The following is a brief introduction. ① If the

Detailed working principle of Hadoop Distributed File System HDFS, Hadoop Distributed File System (HDFS) is a distributed file system designed to run on common hardware. HDFS is a highly fault tolerant system and is suitable for deployment on cheap

Import mysql commands in batches using csv and mysql import using csv Today, the csv data downloaded from Kaggle is imported to mysql. If you want to make a statistical analysis, the csv file is a little large. Therefore, you can only use the mysql

Conversion differences between Oracle and MySQL, oraclemysql 1. nvl function. In Oracle: nvl (join_count, 0) MySQL: if (join_count is null, '0', join_count) 2. String connection. "|" Is used for connection in Oracle, and CONCAT is used for

SQL Server re-learning (1) -- Differences Between varchar, nvarchar, and char, varcharnvarchar SQL Server cannot be lost. review it; Character data with a variable length of n Bytes and non-Unicode length. N must be a value between 1 and 8,000.

Database statement-based table creation, data table copying, and statement copying1. Database tabulation statements Create table tb_People (id integer primary key, Name varchar (255), Sex varchar (255 ))2. Copy data tables from the same database

500th questions, 053500 questions 500. You opened the encryption wallet and then issued the following command:SQL> CREATE TABLESPACE securespaceDATAFILE '/home/user/oradata/secure01.dbf'SIZE 150 MEncryption using '3des168'Default storage (ENCRYPT

Kettle _ creates a carte service for the sub-server, kettlecarte Original works, from the blog of "Deep Blue,Deep Blue blog: http://blog.csdn.net/huangyanlong/article/details/46876783   Create carte in kettle as a windows service item Tip: the

SQL Server time segmentation query, SQL Server time Segmentation Statistical data for consecutive periods if OBJECT_ID(N'Test',N'U') is not nulldrop table Testgo create table Test(pscode decimal(15),outputcode int,monitortime datetime)insert into

383rd questions, 053383383. At the request of a user, you issue the following command to restore a dropped table: flashback table"BIN $ F2JFfMq8Q5unbC0ceE9eJg = $0" to before drop; Later, the user notifies you that the data inTable seems to be very

SQL Sever -- remote process call failed (0x800706be), sever0x800706be Recently, the system has been reinstalled, and VS and SQL Server cannot be used. The following is a summary of the problems encountered in this process. I would like to share my

Hbase-1.0.1 installation, hbase1.0.1 1. Modify the hbase-site.xml configuration file under the hbase/conf directory and add hbase. rootdir hdfs: // master: 9000/hbase hbase. cluster. distributed true hbase. zookeeper. quorum master, slaves1,

[Oracle], oracle Let's say we are going to develop a application for a bank, or any other enterprise, this application need a DB. And we decide to choose Oracle 12c. Then we make a plan: Application is for WBBANK, so name is WBBANK Application

Beckham _ mysql storage engine and transaction concept, Beckham _ mysqlStorage engine and transaction conceptsBrief:1. What is a storage engine?2. What is a transaction?   I. Storage Engine In general, it is the way to store and manage data.

MongoDB query operation (I) (ii): mongodb query operationI. Introduction MongoDB provides db. collection. the find () method is to query the document set and the db that returns the result as a cursor. collection. the findOne () method returns only