Database Administrator

After Oracle (64-bit) and PL/SQL Developer are installed, the following error occurs when PL/SQL is run: My PL/SQL Developer is incompatible with ORACLE, that is, PL/SQL does not support 64-bit ORACLE, therefore, a 32-bit ORCALE client is required

In this Document   Purpose   Details Applies to: Oracle Server-Enterprise Edition-Version 11.2.0.1 and later Information in this document applies to any platform. Purpose This document describes 11gR2 databases

Case study: delete the file system log group and retain the ASM log GroupNote:To migrate an oracle File System to ASM, delete the log Group of the file system and retain only the ASM log group. If both are retained, the read/write log performance is

I learned how to add a table today and wrote a blog to summarize it. PS: All the annotations below are copied to notepad after I complete all the operations on my computer. You can add comments as needed during execution. Select Database Mysql> show

Create an External table with partitions The advantage of creating an external table is that data can be mounted to the table from hdfs at any time. The advantage of using partitions is that the query range can be shortened. The following example

Differences between variable reference methods # {} and $ {} in MyBatis er File By default, MyBatis uses the # {} syntax to generate a PreparedStatement statement and set the PreparedStatement parameter safely. In this process, MyBatis performs

ZookeeperPrinciples of HASH_JIONWhen we associate hash_join, we usually have two tables. The smaller tables are called: the larger build input table. We call it probe input; so how does oracle associate these two tables? First, oracle will select

Background: The company has a stored procedure, and the insert operation is always unsuccessful. After debugging, we can see that the insert statement contains a function for date processing,TO_CHAR (TO_DATE (v_slot_date, 'yyyy-mm-dd'), 'yyyy-mm

PostgreSQL supports hstore to store data such as KEY-> VALUE, which is also similar to ARRAY or JSON. To use this type of data efficiently, you must use efficient indexes. Let's take a look at the performance of two different types of indexes for

Create such a model in the model and write the method to obtain the enumeration class. Please do not pirated, reproduced please add source http://blog.csdn.net/yanlintao1 Class Student extends Zend_Db_Table {Protected $ _ name = 'student ';Protected

I started to install MySQL today. I used to download the installation package from the official website, but it was not available after installation. I guess it was necessary to configure it. I found a lot of information on the Internet and the

Redis is a memory database that supports more value types than memcache. Sina Weibo uses redis for caching. Install redis source codeCopy codeThe Code is as follows:Wget http://download.redis.io/redis-stable.tar.gzTar-zxvf redis-stable.tar.gzCd

For select statements: 1. When a table scan is used, the page is directly locked, instead of locking a specific record. Therefore, these locks are available: A. Database S lock B. Table IS lock C. Page S lock 2. When indexes are used to search for

It is also used for record for future contact! It basically contains the advanced usage of General SQL! Drop table if exists stu; create table stu (name varchar (30), age int, stuid int not null PRIMARY key AUTO_INCREMENT, idnum int, sex varchar (30

Introduction: Redis is a memory-based database. It also provides several persistent solutions that allow users to write data in the memory to the local file system for use after the next restart or after the host. This article describes how to set

In my opinion, since ORACLE has set Automatic scaling, it must have its own intention. How can we use it manually or automatically in the production environment? It mainly depends on the production environment.The first is to check the data volume

I had nothing to do this morning. I suddenly wanted to write views and temporary tables as follows: View: View definition: A table exported from one or more tables (or views. The view and table are different: the view is a virtual table, that is,

When db_block_size is set to different sizes in the local tablespace, the reserved data file header space is as follows :--?? Db_block_size = 2 kb. the file header contains 32 data blocks, that is, 64 KB. Db_block_size = 4 kb. the file header

The check_mysql script is required for mysql slave monitoring and an error is reported during check:Error while loading shared libraries: libmysqlclient. so.18: cannot open shared object file: No such file or directory1. The error message is as

This article does not mention the principles and describes the functions of hadoop and its surrounding projects. The word hadoop has been popular for many years. When it comes to big data, you will think of hadoop. What is the role of