Database Administrator

One of the top 10g features of Oracle is the Advisory Framework, which is a collection of optimization consultants that can help you make full use of your database. One of them, the SQL Access Advisor, recommends that you change the indexes and

Today, we will learn how to operate on the MYSQL installed by default in Red Hat LINUX9.Let's start from the start.Start MYSQL:#> Service mysqld startLog on to MYSQL:#> Mysql-u root-pNote: Here-u represents the user name, while root represents the

There are many application projects. At the beginning, MySQL Databases can basically meet various functional requirements. As the number of application users increases and the amount of data increases, MySQL gradually becomes overwhelmed: the

In linux, only one Oracle database can be created. However, you can create different tablespaces for different users. The format is as follows:Create tablespace vewertemp datafile '\ oracle \ oradata \ viewer \ dbvewertemp. dbf' size 50 M autoextend

(1) back_log:The number of connections that MySQL can have. When the main MySQL thread receives a lot of connection requests in a very short period of time, this works, and then the main thread takes some time (although very short) to check the

After the Linux system is installed by default, there is no built-in database software, which does not meet our needs for Java EE development. Therefore, we need to install the database software by ourselves. Of course, the first choice is MySQL.

Mysql5.x: http://dev.mysql.com/downloads/mysql/5.0.htmlThe above is the official address of mysql. There are too many mysql versions above, and the speed is very slow. We recommend that you renew them from the Chinese website Mysql tool download:

Recently I wrote an Oracle job, which runs at an interval of 1 minute. However, I found that this job was not running. I initially suspected that the time interval was incorrect, but I found that the time interval was not an error. I also suspected

Copy the following code and save it as ***. php. $ User = "database username ";//$ Password = "Database password ";//$ Db_name = "Database Name ";// $ Link = mysql_connect ("localhost: 3306", $ user, $ password );Mysql_select_db ("$ db_name", $

Log on to Linux as an Oracle user Start Oracle: Sqlplus "scott/tiger as sysdba" Startup After entering sqlplus: Take importing and exporting to xzfw as an example. You must have the write permission for/Oracle/oradata/xzfw to perform the

The Oracle display cursor is a SELECT clause clearly defined in the Declaration unit, and a name is specified at the same time.Use this name to reference the cursor attribute canonicalizedly, and use the name to reference and display the cursor in

Method 1: sqlplus "User/password as sysdba" sqlplus "sys/sys as sysdba"Method 2: sqlplus/nolog SQL> conn/as sysdbaSQL> shutdown immediate;SQL> startup mountSQL> ALTER SYSTEM ENABLE RESTRICTED SESSION;SQL> ALTER SYSTEM SET JOB_QUEUE_PROCESSES =

The following is a summary of installing MySQL in Ubuntu 12.04 over the past few days: There are three ways to install MySQL in Linux: the first is to install the rpmbinary file separately, the second is to install the source code after compilation,

1. view the basic attributes of the database:SELECT dbid database number, name database name, db_unique_name global name, created creation time, log_mode archive mode, open_mode access mode, platform_name version type FROM v $ database; 2. view the

Using shell scripts to monitor and manage Oracle databases will greatly simplify DBA workload, such as common instance monitoring, monitoring, and alarm log monitoring, and database backup, AWR report automatic mail, etc. This section describes how

1. Create an array first Create or replace type t_ret_table is table of varchar2 (20 ); 2. Use a custom function to implement 1. Use the function to return an array.Create or replace function f_split_string (var_str in string, var_split In String)

--- SPFILE is created when you use DBCA to create a database.--- SPFILE must be created on the shared volume or shared raw device--- All instances use the same SPFILE--- If you create a database manually, use PFILE to create a SPFILE.[Oracle @ rac11

Initialization parameters related to the Primary role Db_name Db_name must be the same in the same DG Environment Db_unique_name The db_unique_name parameter is an added parameter for the coexistence of multiple instances

1. functions and features of Control Files 1) define the current physical status of the database2) maintain data consistency: If the checkpoints in the control file are consistent with those in the data file, the data is consistent and can be

In the Oracle system, if the remarks field requires 200 Chinese characters, this field is either set to varchar2 (600) or nvarchar2 (200 ). The following provides a reference for saving the length of Chinese characters in the remarks field of