Database Administrator

Note: Cold backup-you can back up a database in ARCHIVELOG mode or a database in NOARCHIVELOG mode. Hot Backup-only ARCHIVELOG databases can be backed up. In other words: ARCHIVELOG mode-cold backup or hot backup. NOARCHIVELOG mode-only cold backup

After mysql is installed, login finds that there are only two databases:Mysql> show databases;+ -------------------- +| Database |+ -------------------- +| Information_schema || Test |+ -------------------- +,Mysql> use mysqlERROR 1044 (42000):

I. AWR usageSQL> @? /Rdbms/admin/awrrpt. SQL Specify the Report Type~~~~~~~~~~~~~~~~~~~~~~~Wocould you like an HTML report, or a plain text report?Enter 'html' for an html report, or 'text' for plain textUlts to 'html'Enter the value of

Oracle 10 Gb provides a web-based management tool db control, which is similar to Oracle 9i OEM tools, but has greatly improved its functionality. A management tool is created when you create a database instance. However, this tool is closely

A redo log group can contain one or more log members, which should be stored on different disks as disk log images. The same group of Members has the same content, the purpose is to prevent all online logs from being lost due to a disk failure. If

Common Operations in the undo tablespace: (1) view the properties of the undo tablespace undotbs1:SQL> select B. tablespace_name, AUTOEXTENSIBLE, RETENTION from dba_tablespaces a, dba_data_files BWhere a. TABLESPACE_NAME = B. TABLESPACE_NAME and B.

1. rm-f system01.dbf 2. Database disconnection Error SQL> shutdown immediateThe ORA-01116: error in opening database file 1ORA-01110: data file 1: '/u01/app/Oracle/oradata/demo/system01.dbf'ORA-27041: unable to open fileLinux Error: 2: No such

-- Book tableCreate table book (Book_id VARCHAR2 (20 ),Book_name VARCHAR2 (100 ),Book_publish VARCHAR2 (100)); -- In indicates the input parameter. The default value is in.-- Out indicates the output parameter.Create or replace procedure sp_pro7

Stored procedures are commonly used in programs, and I often write some in projects. But I make a mistake: I always write the SQL statement process into a long string of SQL statements, run the SQL statement normally. As a result, the code is too

After installing mysql5.1.34 in the upgrade system, I have been too reluctant to install it. I directly downloaded a software package. Today, I took the time to compile and install this version. According to the official statement, several Versions

1. header file. The API is included in the mysqlclient library. # Include -Lmysqlclient must be added during compilation. 2. Create a variableMYSQLMysql The MYSQL structure represents a database connection handle, which is used by almost all MySQL

We only need to bypass hibernate to call the jdbc API. Of course, the transaction is managed by the hibernate industry:Assume that the following stored procedure is created: Create or replace procedure batchUpdateCustomer (p_age in

1 move Experiment SQL> create table my_objects_move tablespace ASSM as select * from all_objects where rownum Table created   SQL> select value 2 from v $ mystat, v $ statname 3 where v $ mystat. statistic # = v $ statname. statistic # 4 and v $

Indexing is a good method for tuning and greatly improving the query speed. However, in addition to creating an index for each field, you can also create an index as follows: 1. Create a joint index for the query condition: Combining all the

I. mysql multi-character set support1. Set the mysqld service to support multiple character sets at the same timeChange the default Character Set of the mysqld service to utf8 and support the latin1, gbk, gb2312, big5, and ascii character sets.

Rollback segment Overview: Rollback segments are used to store values before data modification (including locations and values before data modification ). A transaction can use only one rollback segment to store its rollback information, while a

Record memo: Pfile: Mercury. _ db_cache_size = 289406976 Mercury. _ java_pool_size = 4194304 Mercury. _ large_pool_size = 4194304 Mercury. _ Oracle_base = '/oracle' # ORACLE_BASE set from environment Mercury. _ pga_aggregate_target = 301989888

Export: Release 10.2.0.1.0-Production on Thursday, 22 August 22, 2011 11:08:48 Copyright (c) 2003,200 5, Oracle. All rights reserved. The data pump export utility provides a mechanism for transferring data objects between Oracle databases. The

Several Propagation Features of transactions1. PROPAGATION_REQUIRED: if a transaction exists, the current transaction is supported. Enable if no transaction exists2. PROPAGATION_SUPPORTS: if a transaction exists, the current transaction is supported.

After the server receives the SQL statement, perform the following steps: Parse (resolution)-> Bind (binding)-> Execute (execution ). A flowchart clearly shows these processes: The following describes the specific execution details: 1 Select