Database Administrator

SQL code Select decode (INSTR ('initateaaaa FLOOR ', 'aaa'), 1) FROM DUAL The format of the INSTR method is INSTR (source string, target string, start position, matching serial number) For example, in INSTR ('upgrade FLOOR ', 'or', 3, 2), the

Backup policy: Sunday level 0Monday, second, fourth, fifth, sixth, Grade 2Level 1 on Wednesday -- Create a local management path Mkdir-p/dinglp/ora_managed/backupMkdir-p/dinglp/ora_managed/backupMkdir-p/dinglp/ora_managed/backup/exportMkdir-p/dinglp/

1. ORA-01102: cannot mount database in EXCLUSIVE mode Symptom: SQL> startupOracle instance started.Total System Global Area 1224736768 bytesFixed Size 2020384 bytesVariable Size 318770144 bytesDatabase Buffers 889192448 bytesRedo Buffers 14753792

Environment: Red Hat Linux AS 4 Nahant x86 + Oracle 10.2.0.1 x86This document records the commands used to start and close Oracle 10 Gb database and related files.The three steps for Oracle Database 10g startup are as follows: 1. Create and start

The configuration file of the newly added tablespace mainly uses this parameter.Test EnvironmentInnodb_data_file_path = ibdata1: 370 M; ibdata2: 50 M; ibdata3: 50 M; ibdata4: 500 M; ibdata5: 500 M: autoextend There are several situations1. During

If the web and database are not on the same server, the MySQL server must allow remote connections to run the website properly. There are two ways to set the remote connection of MySQL: 1. Change the table. It may be that your account is not

The first time I met Oracle, I sorted out some simple and practical solutions. Confirm orcale Recognition-it is a annotator, not recognized # Length () is a string length function, not len () Table Dual: system table, with only one option

1. Ensure that the system users you log on to have sufficient permissions. Windows: add your users to the Oracle DBA Group. Use root to log on to UNIX. 2. Run sqlplus/nolog in command 3. Enter the conn/as sysdba after the SQL> command If the

1. First, add the scheduled task to the list. The system scans the task list every minute to check whether the task is to be executed at the current time. /etc/crontab:  # m h dom mon dow user    command    0 1  *   *  *   root    /home/fzw/

SQL> create tablespace test datafile 'y: \ test. dbf' size 20 M; The name of the actually created tablespace is TEST. Execute the following three commands to delete the tablespace: SQL> drop tablespace test; The tablespace has been deleted. SQL>

The main body of Oracle functions is as follows: Create or replace function fn_get_agmt_bal (p_agmt_no varchar2)RETURN NUMBER ISV_bal NUMBER: = 0;-- If dbms_output takes effect during SQL/PLUS execution, run [SET SERVEROUTPUT ON] first

This article describes eight common shell scripts for monitoring data. First, I reviewed some common DBA Unix Commands and explained how to regularly execute DBA scripts through Unix Cron. There are also a lot of similar articles on the Internet,

Problem:Org. postgresql. util. PSQLException: Connection refused. Check that the hostname and port are correct and that the postmaster is accepting TCP/IP connections.Solution: Edit/var/lib/pgsql/data/postgresql. conf fileChange# Listen_addresses = '

Method 1 for Oracle to implement the fibonacci series: Select replace (MAX (SYS_CONNECT_BY_PATH (fib | ',', '/'), '/', '') | '...' fiblistFROM (SELECT n, fib, ROW_NUMBER ()OVER (order by n) rFROM (select n, round (1 + sqrt (5) * 0.5, n)-power

The MEMORY_TARGET parameter was introduced in Oracle 11g, mainly used to control Oracle's use of system memory. For the first time, the SGA and PGA were integrated for automatic management. Once the MEMORY_TARGET parameter value is set, Oracle will

Backup:Back up a database (execute in shell, the same below ):Mysqldump-uusername-ppassword-hhostname -- databases db_name>/path/db_name. SQL Back up multiple databasesMysqldump-uusername-hhostname-ppassword -- databases db1_name db2_name

When installing Oracle in Linux, swap is insufficient. solution: Root User 1. Add a file system (The following is an example of adding a file system of MB) Dd if =/dev/zero of =/home/oracle/myswaps/swapfile1 bs = 1 M count = 512 Note: The path

Because a large amount of data exists in text files and needs to be imported to Oracle, we are lucky to have access to the arms SqlLoader. Run the sqlldr command on the host where Oracle is installed.Sqlldr You will see instructions on this tool:

1. Create a databaseMysql> create database if not exists tongcheng;Query OK, 1 row affected (0.01 sec)Mysql> 2. view the options when creating a databaseMysql> show create database tongcheng;+ ----------- + -------------------------------------------

Because Oracle 11gr1 needs to be installed on RHEL5.5 for testing, there are many problems, first sort out the following and search a lot online Reference connection, oracle documentation: