Database Administrator

Basic Oracle database operation statements This article mainly introduces the basic statements and concepts of Oracle database management. 1. How to query the permissions of a role?A. System permissions contained in a roleSelect * from dba_sys_privs

Oracle 11g detailed steps for building a standuard (physical standby all operations) Preface: DataGuard establishes a reference relationship by establishing a PRIMARY and STANDBY group. Once STANDBY is created, DataGuard passes the REDO of the

Procedure for Incomplete recovery across instances based on innobakcupex On the basis of Hot Standby, MySQL can achieve full or incomplete recovery of the original Instance. In many cases, DRBD or MHA is deployed on the original instance. In this

Oracle creates tablespaces and users Oracle creates tablespaces and users 1. Connect to the database# Su-oracle$ Conn/as sysdba 2. Create a tablespaceSQL> create tablespace doiido datafile '/main/oracle/oradata/doiido. dbf' size 1024 M autoextend

Difference between inner join and left join in SQL statements: innerjoin The project requirement is changed. I wrote a query SQL statement, which needs to be modified. I haven't changed it for a long time. Finally, I want to join the SQL statement ),

Solution to mysql installation failure on Mac, macmysql The version I installed is a mysql-5.6.21-osx10.9-x86_64.dmg that prompts installation failure on Mac OS X 10.10, as shown in. Solution In step 3 of the installation process, select Custom

Oracle Spool command and oracleSpool command Run the spool command to copy the output results of SQL * plus to a specified file or query the results. Send to the printer and use the spool off command until it is executed.The spool command syntax

Change the version of the dmp file imported from oracle.Today, the customer gave me a table data file exported from the oracle11g database. The file suffix is the dmp file. I imported the dmp file into our business database and reported an error,

SQL optimization -- Logical optimization -- condition simplification, SQL -- 1) query Conditions Query condition concept: In SQL query statements, the expressions used to filter and connect tuples are expressions in the WHERE/JOIN-ON/HAVING

Redis database of 03_NoSQL Database: list type, 03_nosqlredisZookeeper Lists type and Operation List is a linked List structure. The main function room is push, pop, get all values in a range, etc. In the operation, the key is interpreted as the

Oracle get command and Oracleget commandOracle can use the get command to read file content to the buffer zone,The get command syntax is as follows:Get [file] file_name {list | nolist]File_name indicates an external file, which is included in the

Mysql and Oracle Database concat () functions, oracleconcat I. Different Function Parameters Mysql supports concatenation of multiple strings: CONCAT (str1, str2 ,...) Oralce only supports concatenation of two strings. To splice multiple strings,

In Linux, mysql forgets the root user password, and mysqlrootToday, 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

Oracle SQL optimization set and oraclesql Optimization **************************************** * ******************** 1. create an optimization set object ************************************ * ********************** --- authorize grant administer

In Linux, Mysql table names are case-insensitive and mysql is 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

Kettle connection Cluster Environment configuration, kettle Cluster Environment Original Works are from the blog of "Deep Blue blog". You are welcome to reprint them. Please note the following source when reprinting them. Otherwise, you will be held

Mysql client data garbled, mysql client garbled Garbled characters appear when inserting Chinese data into mysql: Mysql> select * from test;+ ------ + ----------- +| Id | name |+ ------ + ----------- +| 1 | why does one fail? || 2 | too many threads?

Scrolling result setA scrollable result set means that when reading records in the database, we do not need to read the records one by one. Instead, we can skip several records based on our specific needs before reading the results.The two

Use of packages in OracleUse in Oracle The main purpose of using a package is to modularize the program. The package can combine the relevant stored procedures, functions, variables, constants, cursors, and other PL/SQL programs, in this way, code

Oracle 11g adds a control file to the ASM disk, 11 gasm A Control File is one of Oracle physical files. It records the database name, data File location, and other information. The importance of the control file is that the database will go down