Database Administrator

Oracle sequence, index, and synonym A simple record of knowledge about Oracle sequences, indexes, and synonyms. 1. Common database objects Ii. Sequence Sequence: a database object that can be used by multiple users to generate unique values.

Use MyBatis Based on XML, and use MyBatis for XML 1. Project Structure 2. entity Student package net.hw.bean;/** * Created by howard on 2016/4/25. */public class Student { private int id; private String name; private String branch;

17.3. Making User-Managed Backups of Offline Tablespaces and DatafilesPay attention to the following guiding principles when backing up offline tablespaces:(1) tablespaces that cannot be offline system tablespaces or active rollback segments(2)

1. Summary Because of the complex pattern and different information descriptions of graph databases, it is extremely difficult for non-professional users to query complex graph databases. A Good Graph query engine should support conversion of

Search for records with all repeated titles: SELECT * FROM t_info a WHERE ((SELECT COUNT(*) FROM t_info WHERE Title = a.Title) > 1) ORDER BY Title DESC 1. Search for duplicate records 1. Search for all Repeated Records Select * From table Where

The following articles mainly describe the actual operation procedures of some records of MSSQL to MySQL database, as well as the problems found in the actual operations, including the problem of table creation and coding, the following describes

I made a php program to add form data to the database. I used the mysql extension library function to perform operations on the mysql database to add, delete, update, and query words. The running environment is a common mysql database, php, and

I. Preface Oracle provides PL/SQL developers with a tool to encrypt the code they write (the objects Package, Procedure, Function, and Java Source in oracle. After PL/SQL code is encrypted, it is described as "encapsulated ". Use the wrap tool to

Oracle users have relatively large permissions. Therefore, you may need to use non-oracle users to manage related databases. In particular, it is necessary for multiple individuals to add different users to the system or database, and then add these

Each database of Sybase SQL Server, whether it is a system database master, model, sybsystemprocs, tempdb) or a user database, has its own transaction log, and each database has a syslogs table. Logs record user operations on the database, so if you

Checkpoint, also known as a checkpoint, means that all the dirty data is written back to the disk in Oracle. The database achieves consistency and data integrity. Oracle performs transaction rollback with the latest checkpoint as the reference point

The architecture of Replica Sets + Sharding is as follows: 1. shard server: Use Replica Sets to ensure that each data node has the backup, automatic fault tolerance transfer, and automatic recovery capabilities. 2. configuration server: use three

It is hard to know why a system is slow in running and performance degrades. Is it a memory leak, a bottleneck on the disk subsystem, or is there a limit on the scalability of a specific application? There are some ways to discover and understand

View is one of the most basic and important functions for databases. The design of the database view is directly related to the database performance. In addition, in the design of large databases, the division of labor and cooperation, the design of

The data dictionary in Oracle is a very important part of the database and provides information about the relevant database. It is used by all Oracle users (from application end users, application design developers to database administrators) is a

If you use the default Oracle creation method when creating foreign key constraints, you cannot delete the referenced data. This gives us more flexible options in Oracle9i, however, we use the on delete cascade and on delete set null keywords to

Server clusters take advantage of the built-in cluster functions in Enterprise Edition of the Windows Server series. In fact, Windows Server 2003 is much better for clusters than Windows 2000 Advanced Server. To maximize the benefits you get from

Oracle Database pioneered the design concept of tablespace, which makes an indelible contribution to the high performance of Oracle Database. In this case, many Oracle optimizations are implemented based on the tablespace design concept. Typical

The unique value insertion solution for unique columns in this article is mainly based on the MySQL platform. Through this, you can achieve some new functions and applications. I hope this article will help you. When a unique column inserts records

BMC Software company NASDAQ: BMC) today announced the acquisition of GridApp system company (hereinafter referred to as "GridApp "). As a private enterprise, GridApp is an industry-leading provider of automated database supply, patching, and