Database Administrator

By default, for security reasons, the MySQL database in Linux shields remote access. However, in many cases, you need to access the remote database server at home or from a web application, which is quite troublesome. Step 1: Activate network

After installing the OOracle software on the Linux platform, you do not need to use dbca to create a database, but manually create a database. The main purpose is to understand the operations performed during database creation. 1. First set the SID

I have always wanted to take a good look at Oracle, but now the item is about oracle Security. So, take a moment to sort it out. Although it is impossible to fully understand oracle, but it is better to do it than not. I. ORACLE instances　　1. ORACLE

I use Ubuntu 10.04 and install rlwrap using sudo apt-get install rlwrap. The usage is: rlwrap sqlplus. After entering, you can use the direction key. You do not need to enter rlwrap to modify your bashrc and add alias sqlplus = 'rlwrap sqlplus '.

MongoDB is a scalable and high-performance next-generation database. Data in MongoDB is stored as documents, so that complex relationships can be expressed in a single data object. A document may consist of the following parts: an independent basic

In data development applications, data needs to be sorted in most cases. However, in Oracle databases, there is a NULL value ). If some values in a column are empty, if this column is sorted, the rows with null values are sorted at the end, for

Oracle has db_block_size and the operating system also has block size. The following is a brief introduction. AIX: View the size of each block in the AIX operating system: # Lsfs-q/u01 Name Nodename Mount Pt VFS Size Options Auto

There is a table in the Oracle database. You can use PL/SQL to check that the index of the table is not dropped, but the data query on the table is very slow (the query time is about three times the original time ), then I rebuilt the index. Why is

Create type char_table is table of varchar2 (4000); -- create a custom type script Create or replace function split_string (pi_str in varchar2, pi_separator in varchar2) -- create a functionReturn char_tableIsV_char_table char_table;-- Create type

1. Install the Red Hat 5 system on the Virtual MachineVirtual Machine version: vmware workstation 7.11 build-282343Red Hat 5 version: [Red Hat Linux.5.5.for. x86. Server Edition]. rhel-server-5.5-i386-dvd(1) file → new → viutual machine on the

When you use Database Link to integrate a remote Database, the system returns the ORA-22992 error when querying Blob fields from the remote Database. Some people use materialized views to solve this problem, but the synchronization mechanism of

Background description In the process of developing Oracle forms, Uniqueness verification and repetitive verification are one of the most basic form verification functions. Generally, the uniqueness verification can meet the requirements of daily

Generally, the master/slave Mechanism Based on LAN can meet the requirements of 'realtime' backup. If the latency is high, first confirm the following factors: 1. network latency2. master Load3. slave LoadThe general practice is to use multiple

ORA-02082 CREATE DATABASE LINK Connect to username identified by password USING 'service name '; The Link name and service name cannot be the same SQL> create database link OMS connect to OMSUSER identified by password using 'oss _ 10.2.8.1 ';

A business table contains the following fields: province name (Csqmc), Province code (Csqdm), city name (Csxmc), and city code (Csxdm ). By selecting the province/region name, city/county names are linked. 1. No Csqmc or Csxmc fields exist in

Use of Oracle Flashback table Oracle ensures that recyclebin is enabled SQL> show parameter recyclebin NAME TYPE VALUE-----------------------------------------------------------------------------Recyclebin string ON creates a table SQL> create table

I use ssh for remote configuration. The configuration is slightly different.1. Install MySQLSudo yum install mysql-serverSudo chgrp-R mysql/var/lib/mysqlSudo chmod-R 770/var/lib/mysqlSudo service mysqld start Set the password for the first

This article introduces flume data insert hdfs and common directory (), this article continues to introduce flume-ng to insert data into the hbase-0.96.0. First, modify the flume-node.conf file in the conf directory under the flume folder in node

The day before yesterday, the deployment and implementation company xx production center entered a set of DG databases, but before that, one of the primary was a test machine before I N. I remember that I installed version 11.2g 03 in the form of

Oracle Server: Select * from NLS_database_PARAMETERS where parameter like '% CHARACTERSET % ';PARAMETER VALUE----------------------------------------------------------------------NLS_CHARACTERSET WE8MSWIN1252NLS_NCHAR_CHARACTERSET AL16UTF16 Table t1: