Database Administrator

The installation of the MySQL-Proxy binary version is relatively simple, and does not need to be repeated. The following describes how to install the source code for Linux: Install pkg-config: Tar zxvf pkg-config-0.23.tar.gz Cd

PhpWhen the script is running, the data is stored in the memory,ArrayAndMysqlThe result set is a common data type. The memory usage of the two data types is tested.  Research and useMemory_get_usage (true)View memory

1. First set Oracle_SID = manual2. Create a password fileGo to the/u01/app/oracle/product/10.2.0/db_1/dbs directory and run the command to create the Database Password File.[Oracle @ myorcl dbs] $ orapwd file = orapmanual password = oracle3. create

1. Data Guard master database archive deletion policy: When we set: RMAN> configure archivelog deletion policy to applied on standby; In Maximum Availability and Maximum Performance, when RMAN backs up the archive file and adds delete input, the

In Oracle 11 g2, duplicating a database has two methods: 1. Active database duplication2. Backup-based duplication The advantages of using duplicate for a database are:Test backup and recovery proceduresTest an upgrade to a new release of Oracle

Lab environment, Oracle 11gR2 standalone test data software and database upgrade, operating system Linux6.3Oracle version 11.2.0.1 upgrade package 11.2.0.3After the database software and database are upgraded successfully, the following error is

In non-relational database MongoDB, there is no ready-made framework that can easily implement database grouping through Group By like SQL. If we want to implement the MongoDB Group function, we must write the original NO-SQL query statement to

1. Close the database completely. 2. Close the database and modify the server parameter file to use Oracle Managed Files (OMF ). 3. edit and execute the following RMAN Script: startup nomount; restore controlfile from '/u1/c1.ctl'; alter database

Recently, my colleagues reported that the database could not perform some data dictionary queries. An error occurs even when you query dba_users. From the error log, all are some error information of the data dictionary, and the user data is OK.

Mysql uses the InnoDB Storage engine by default from 5.5. to use the InnoDB Storage engine, you must add the compilation parameters when compiling and installing mysql. The compilation parameters of different versions are also slightly different,

Rowid is literally interpreted as a row ID. In Oracle, rowid is the fastest and most effective way to locate records. So how does rowid locate the record in oracle? And why is it the most effective way? With these problems, let's unveil the mystery

System Environment: Operating System: RedHat EL55 Oracle: Oracle 11.2.0.1.0 Case: The archive log space of the client database server is full and not found. After the DBA finds that the log switch is hang, the database is forcibly shut down, causing

During the test today, I want to query the tablespace information corresponding to the data file. In the desc dba_Data_files view, I found that this object does not exist. At that time, I thought it was normal that my DB could not be queried under

When the Oracle database is started, it encounters bad blocks, especially some underlying tables in the SYSTEM tablespace, such as UNDO $ and OBJ $, which may cause the database to fail to open normally, of course, you can add some hidden parameters

An error occurred while installing Oracle10G runInstallert on AIX. Environment: System: AIX5300-08 Database: Oracle 10g (64bit) After the oracle software is uninstalled on the AIX client, a daily error occurs: Check whether the system

Symptom:An error is reported in the alert Log when the Oracle database is started:SUCCESS: diskgroup DATADG was mountedErrors in file/oracle/app/11gR1/diag/rdbms/rac/rac2/trace/rac2_mmon_1_6.trc (incident = 240612 ):ORA-00600: internal error code,

The new feature of user rename is provided from Oracle 11.2.0.2. in earlier versions, If you need rename username, we generally use imp's fromuser, touser, and Data Pump impdp's remap_schemas. If we want to import a schema data to replace the

Running Environment: Ubuntu + Oracle 11.2.0 ORA-12547: TNS: lost contact error occurs when the command starts oracle. Good afternoon, no matter in the afternoon. If the link is invalid, it will not work after Shutdown and restart. Then google found

Login connection errors are the most common problems we encounter during Environment configuration, changes, and new Client installation. The logon process involves the client network, operating system, TNS configuration, listener working status,

1.1.1. ORA-19502, ORA-27072 Date: Environment: Testing Machine [Error code] $ Oerr ora 1, 19502 19502,000 00, "write error on file \" % s \ ", block number % s (block size = % s )" // * Cause: write error on output file // * Action: check the file $