Database Administrator

The sixth day of oracle learning and the sixth day of oracle LearningZookeeper 1. Review in the previous section2. PL/SQL Introduction3. Basic PL/SQL Understand oracle pl/SQL conceptsMaster PL/SQL programming technology (including programming

Queries the minimum wage information of each department and the department wage information. Example: Query the minimum wage information of each department Join subquery Method 1. query the minimum wage of each department select deptno, min(sal)

Oracle user management instance, oracle user management User Roles in oracle are divided into predefined roles and custom roles.A role is a combination of common permissions to form a role.Authorization/Role Assignment CommandGrant permission/role

SQLServer remove and add releases without initializing all projects. -- If you disable schema change in advance, the newly added columns will not automatically add a large distribution. In this case, use sp_articlecolumn to add the column EXEC

Article Title, article title DaquanNoSQL database product learning Summary (1) This article is divided into four chapters, and will gradually sort out the knowledge of Memcached, Redis, tair, mongodb, hbase, SequoiaDB, and Cassandra. This article

Comparison between SQLServer and Oracle: SQLServerOracle I recently went to iron University for an interview. The project leader asked me the following question: what is the difference between SQL Server and Oracle? From entering the software

[Mysql] daily backup shell script and mysql backup shell script Use mysqldump to back up mysql Data at a fixed time every day. #! /Bin/bash # mysql backup data orangleliu # chmod 700 backup every morning. sh # crontab-e #0 4

Change User Name in ORACLE and Change User Name in oracle Oracle user passwords have been frequently modified before, but few user names have been modified. In the past, only one user 1 can be created, user 2 data can be imported to user 1, and

In MySQL, the statement locate position instr find_in_set and locatefind_in_set are more efficient than the like statement.Are you always looking for more efficient methods than the LIKE Statement of MySQL? I will introduce you to several methods

An exception occurred in the SQL Execution Plan after flashing back to drop to restore the table.----- Normal execution planSet autotrace traceonlySet linesize 1000Select/* + index (t idx_object_id) */* from t where object_id = 19;Execution Plan-----

[Err] 1136, err1136 1 error description [Err] 1136-Column count doesn't match value count at row 1 Procedure execution failed1136-Column count doesn't match value count at row 1 2 error cause During the storage process, when a temporary

Mongodb Study Notes 04, mongodb Study NotesCursor Var cursor = db. collectionName. find () create a cursor Whether cursor. hasNext () has the next element Cursor. next () retrieves the next element, for example, while (cursor. hasNext ()

Introduction to MySQL event scheduler, mysql event Scheduler How to Use the MySQL event Scheduler The Event sched feature has been added since MySQL5.1.0. It can be used for scheduled execution of certain tasks and can be seen as a time-based

MySQL: root Login for multiple instances on one host, mysqlroot If multiple MySQL instances are created on one machine, for example, the port number is 3306,330 7, 3308 Select a different mysql. sock file when logging on. Mysql-uroot-p123456

Oracle442 Application Instances ---------- overview file, Overview Design Manual instance ------------------------ Brief Description :---------------------------------In order to rationally allocate and use system resources, the Oracle system puts

Oracle442 Application Instances ---------- initialize parameter files and oracle initialize parameter files ---------------- Initialize the parameter file --------------------Before 9i, the initialization parameter file used by oracle is pfile. 9i

Mysql index Overview An index is essentially a type of table. This type of table stores the column values listed as indexes and pointers pointing to real complete records. The index is transparent to users and is only used by the database engine to

Factors to consider before upgrading to Oracle DB 12c: the feature of EM Express 12c in DB 12c is reduced, oracle12c Considerations before upgrading to Oracle DB 12c: the feature reduction of EM Express 12c in DB 12c If you have used the features

Normal database hang is disabled. normal database hang To avoid problems caused by abnormal shutdown, we have a test database that uses shutdown normal to stop the database. The result is that the hang is very common. Operation Sequence:1. shutdown

Redis client protocol parsing, redisprotocol On the official website, visit http://redis.io/topics/protocolto describe the rediscommunication agreement.For the following reasons, I want to parse the redis client protocol: 1. Be familiar with