Database Administrator

Detailed steps and precautions for building a single instance DG for two Oracle 11g nodes RAC Environment Introduction: OS: [root @ java3 ~] # Uname- Linux java3 2.6.18-308. el5 #1 SMP Tue Feb 21 20:06:06 EST 2012 x86_64 x86_64 x86_64

Adding not null constraints to Oracle When creating a table, Oracle adds the not null constraint to the column in the following format:Column_name data_type[Constraint constraint_name] not nullConstraint constraint_name indicates the name specified

MySQL startup error solution case After installing LAMP on a newly installed CentOS server, restart the system and find that MySQL cannot be started and the following error is reported: /Etc/init. d/mysqld startStarting MySQL... ERROR! The server

Creating large file tablespaces in Oracle Large file tablespace is a new tablespace type introduced in Oracle 10 GB and later versions. It is mainly used to solve the problem of insufficient storage of large files. Unlike Common tablespaces, large

How does MySQL track SQL statements? In project development, it is inevitable that you need to track SQL Execution statements on the database server. By tracking SQL Execution statements, we can determine that When Upper-layer applications are

How to import SQL files in Centos, centos import SQL files For File Import, In Centos, you must first create a database with the same name as the file. For example: mysql> create database Student; Then enter the command: mysql> use Student; If

Oracle constraint classification, oracle constraint classificationDatabase Integrity is the correctness and compatibility of the data in the database. It is used to prevent users from adding invalid semantics to the database. Database integrity is

Check the database again -- (6) connection and database connectionIntroduction: Join is the basis for multi-table queries. Because relational databases do not contain pointers or other associated records and records, the connection is the only

Create join and cross-row computing reports In actual information systems, a lot of data computing is performed for front-end display. Reports are the most common form. These computing implementation processes are often not simple, and it is

Add not null constraint and constraint lenotnull constraint to oracleWhen creating a table, add the not null constraint to the column in the following format:Column_name data_type[Constraint constraint_name] not nullConstraint constraint_name

OCCI processes different CHAR string variables, occichar Problem background: An old application, originally written In proc, is a 9i Database. Now, the application needs to use OCCI instead, with a query logic: select... where upper (state) = upper (

SQLite getting started, sqliteWhat is SQLite? SQLite is a lightweight embedded database. It occupies very low resources. In embedded devices, it may only need several hundred KB of memory. It processes faster than MySql and PostgreSQL, both

Ado connects to SQL server and adosqlserver // Add the following sentence to the SQL server connection header file of ado: # import "C: \ Windows \ system \ msado15.dll" no_namespace rename ("EOF", "rsEOF ") // CoInitialize (NULL) in cpp ); _

Swift version of SQLite help class, Swift version of SQLiteSQLiteHelper create SQLiteHelper class /// SQLite database processing Help class ///// this class encapsulates the business function class SQLiteHelper for SQLite database processing {//

Before dropping a user, we recommend that you obtain the user's dependency. Before deleting these two users, we recommend that you obtain their dependencies: SQL> col owner format a15SQL> col name format a15SQL> col REFERENCED_NAME format a30SQL>

Data Center reconstruction-stored procedure and stored procedure Reconstruction I have only seen the word stored procedure. I know such a thing, but I didn't really reveal it to really understand it. But I encountered a problem when I knocked on the

Redis, Memcache, Mysql difference, redismemcache When using Redis, we found that Redis is different from Memcached and also different from MySQL.(This article mainly discusses the situation where VM support is not enabled for Redis)1. Schema MySQL:

Difference between @ param in spring and @ param in mybatis, @ parammybatis /*** Query whether the specified user and enterprise are associated with a configured role * @ param businessId memberId * @ return */int selectRoleCount (@ Param

[PLSQL] process procedure parameters and real parameters, plsqlprocedure**************************************** ********************************* *** Original article: blog.csdn.net/clark_xu Xu changliang's column************************************

Oracle query sequence and oracle Sequence Query the sequence of a user, where user_name is the login name of your current database SQL> select SEQUENCE_OWNER, SEQUENCE_NAME from dba_sequences where sequence_owner = 'user _ name '; SEQUENCE_OWNER