Database Administrator

Purpose: compile a shell script to export data from mongoDb to a csv file. Requirements: 1. To avoid exporting massive amounts of data, you only need to filter out the data for the current month and the data for the previous month. 2. Because the

Oracle log mining (LogMnr) ① Set the utl_file_dir path in the parameter file ② Restart ③ Create directory file and use execute dbms_logmnr_d.build () ④ Add a log file and use dbms_logmnr.add_logfile Or delete the log file, use dbms_logmnr.removefile

1. query and modify the undo_retention parameter: Run the show parameter undo command to view the current database parameter undo_retention settings. Shown as follows: Undo_management string AUTOUndo_retention integer 10800Undo_suppress_errors

DataGuardAbbreviationDGIs a database-levelHAThe main functions of the solution are redundancy, data protection, and fault recovery,DGProduction database"Transaction consistencyCopy ",Use the physicalCopyAfter the slave database is created, the

Here we will introduce in detail how to compile and install mysql with a non-root Account: 1. Create a mysql account with rootUseradd-m mysql 2. Download mysql-5.1.58.tar.gz from the official website and put it in/home/mysql/software. Unzip the

The project finds that the query response is very slow, takes time to analyze and optimize, and is specially recorded. (1) Background The project adopts the MySQL database and Ibatis; (2) query description This query is used to query a certain

Oracle 10 Gb provides a new performance collection and analysis tool awr (automaticworkload repository ). Awr exists in the sysaux tablespace and is one of the main users of sysaux. Snapshot, a set of performance statistics captured at a specific

Today, at the customer's request, the password for creating a user must be the same as that for the source database. However, I found that the source database password is 123456, which is very simple and starts with a number. This Oracle is not

1. Sequence creation and description Create a sequence. The syntax format of the Oracle sequence is:Create sequence name[Increment by n][Start with n][{MAXVALUE/MINVALUE n | NOMAXVALUE}][{CYCLE | NOCYCLE}][{CACHE n | NOCACHE}]; 1) increment by is

The imp command is executed at the dos prompt.Run the command directly after cmd instead of in SQL. Data export:1. Export the database TEST completely, and the username system Password manager is exported to D: daochu. dmp.Exp system/manager @

HOST-> sqlplus "/as sysdba"   SQL * Plus: Release 11.2.0.1.0 Production on Thu Dec 1 10:13:58 2011   Copyright (c) 1982,200 9, Oracle. All rights reserved.   Connected to an idle instance.   SQL> startup ORA-01078: failure in processing system

1. Configure link information Open PowerDesigner and click Database ---> Configure Connections in the main menu to select Connection Profiles 2. Add a data source. Click Add DataSource in. 3. Click Test Connection to Test whether the

I. system environment: CentOS 1, 5.5 Host (MASTER): 192.168.0.10 SLAVE (SLAVE): 192.168.0.20 Install Mysql in yum on slave # Yum install-y mysql-server Do not enable the mysql service. Copy the/etc/my. cnf file on the master to the/etc directory on

1: Data Export command Declare --- Create a data pump handle H1 number; Begin -- Create a user-defined Data Pump for schema backup H1: = dbms_datapump.open (operation => 'Port', job_mode => 'scheme '); -- Define storage files Dbms_datapump.add_file (

Solution 1: merge into statement: MergeIntoExcel e Using (SelectEt .*FromExcel_temp etWhereEt. id ='1') Tmp On(E. root_affair_code = tmp. root_affair_code) Note that:OnThe following condition must be that the candidate code in using (tmp in

There are many ways to get the execution plan of Oracle. Here we only introduce a few of them.(1) To get plan from MemoryFor SQL ID:Select * from table (dbms_xplan.display_cursor ('& SQL _id '));Select * from table (dbms_xplan.display_cursor ('& SQL

The role of undo tablespace and redo log files in Oracle is very important. This article focuses on the role and features of undo rollback segments, and briefly introduces the differences between undo and redo and their respective roles: 1. Features

In Greenplum, it is difficult to obtain the field names after execution of any SQL statement. For example, when writing a common tool, you can use the copy command to export an SQL statement to text, but the text exported by the name of each field

Check whether the Oracle database is in archive Mode1. select name, log_mode from v $ database;NAME LOG_MODE------------------------------------------ QUERY NOARCHIVELOG 2. Use the archive log list Command Database log mode No Archive Mode Automatic

1. Install related software packages The list is as follows: Binutils-2.15.92.0.2-13.EL4Compat-db-4.1.25-9Compat-libstdc ++-296-2.96-132.7.2Control-center-2.8.0-12Gcc-3.4.3-22.1.EL4Gcc-c