Database Administrator

How to view the usage of some commands in SQL * plus Sometimes I forget the usage of some commands when using SQL * plus. In fact, we don't have to look up anything. We just need to check it in SQL * plus, Use help |? Parameter For example, in SQL *

Oracle Database version on RHEL 7 RHEL 7 was available for download in 2014. The following information can be found in the "authentication" section of MOS:12.1.0.2 has passed the authentication on rhel7.12.1.0.1 has not passed the authentication on

Use the mysqlhotcopy command line tool to create a backup Use the mysqlhotcopy command line tool to create a backup: Mysqlhotcopy is a script written in Perl. It encapsulates and calls flush tables, lock tables, cp/scp, and other commands to create

InnoDB modifies the table object structure online Modify the table object structure online: Before MySQL5.6 1. Create a temporary table with the same structure as the original table object (invisible to users by implicit operations) and change the

Preparations before deploying SQL Server on the new Server When you need to deploy a new server, you may encounter many mistakes if you have no deployment experience, and make the maintenance work more difficult in the future, here I will share

MySQL client output window display Chinese garbled Problem Solution Recently, it was found that when querying table data in the MySQL dos client output window, Chinese data in the table is displayed as garbled characters, as shown in: Check the

Resolution case with ORA-39154 errors when impdp is executed A data table Import and Export Operation encountered a ORA-39154 when using impdp import, it took some time to solve.Below I actually restored this error in the test environment, and

Analysis Steps for slow OGG rep running Analysis Steps for slow OGG rep running: 1. Perform ps-ef | grep according to the rep process name to obtain the rep process PID. [Oracle @ hosta ~] $ Ps-ef | grep repfullOracle 27906 27861 0 pts/7 S + \ _

In Linux, MySQL forgets the root user password. Today, when receiving a MySQL server, I found that I forgot the password of the root user of MySQL. I found that no root user password exists in various documents. Therefore, I need to modify the

MySQL table names in Linux are case-insensitive. Scenario: Recently, the company switched the database from Oracle to MySQL. Since the table names in Oracle are case insensitive, the problem of table names not found in MySQL occurs, it is found that

How Does oracle rac correctly Delete the actionlist and racactionlist of a single node? 1 Node 2 Use dbca to delete a node 2 node 1 alter database disable thread 2; 3 Node 1 verify whether a node database has been deleted [03:49:06 oracle (db) @ rac1

MySQL Chinese insert error Incorrect string value: '\ xCC \ xEC \ xB2 \ xC5', xccxecPreface:Failed to input Chinese characters, error: Incorrect string value: '\ xCC \ xEC \ xB2 \ xC5', as shown below:Mysql> set names utf8;Query OK, 0 rows affected (

Install mysql in Linux and mysql in LinuxI. Simple Installation# Yum install-y mysql-server mysql-develIf an installation package conflict is reported:File/usr/share/mysql/ukrainian/errmsg. sys from install of MySQL-server-5.5.18-1.rhel5.i386

Invalid ale Data Processing and constraints, and invalid ale Data ProcessingOther DML statements for data processing: Constraints Constraint is a provision** NOT NULLUNIQUEPRIMARY KEYFOREIGN KEYCHECK **You can create constraints when creating tables.

Oracle 11g installation and configuration EM, 11gem You cannot log on to EM. If you execute emca-config dbcontrol db, you do not know that the default port number is 1522. But google will execute the command in step 2... (My listeners are fine)

Basic principles and principles of locksBasic Principle of oracle032 lock1. Oracle lock typeLock function: protects data, and no concurrency is available without locks. The lock is used to limit concurrency.Slow database response may not be due to

Xinxing analyzes the ordered collection in Redis, and Xinxing analyzes redis The sorted-set in Redis is similar to the set. It is a string set and duplicate members are not allowed to appear in a set. The main difference between an ordered set and a

Xin Xing talks about Redis transactions and Xin Xing talks about Redis transactions Redis also provides support for transactions. In Redis, we commonly use four commands: multi, exec, discard, and watch. The multi command is used to start a

Mysqlbinlog can not parse row based events, mysqlbinlogparse During the recent MHA test, the version of the mysqlbinlog client is lower than that of the server. The error message is mysqlbinlog is 3.2 (encoded in MySQL Client 5.0 or lower), but

Difference between insert table and create table as, insertcreate Author: iamlaosong First, the biggest difference is that the two are different types of statements. The former is DML statements (data operation language, SQL processing data, and