database table field

In order to build a database with small redundancy and reasonable structure, we must follow certain rules when designing database. In a relational database, this rule is called a paradigm. A paradigm is a summary of a design requirement. In order to

1. First paradigm (ensuring that each column remains atomic) The first paradigm is the most basic paradigm. If all the field values in a database table are non-exploded atomic values, the database table satisfies the first paradigm.The

Small series has been wanting to know, how to build a database, here to share some of the preparatory work before this, first of all the small part is the first to understand the database (MySQL), the following is a small part of the

I. Statement manipulation of tables1. Create a tableCREATE TABLE Login(UserName varchar (primary) key,--the primary key.Primary KEY (Code,chengwei)--Federated primary KeyPassword varchar () NOT NULL,--cannot be a null value.Name varchar (unique)--a

Reprinted from: http://www.cnblogs.com/linjiqin/archive/2012/04/01/2428695.htmlThree paradigms of database designIn order to build a database with small redundancy and reasonable structure, we must follow certain rules when designing database. In a

First, the problem leadsWhen installing MySQL is to configure its encoding format to Utf-8, so at this point MySQL character_set_client, character_set_connection, Character_set_database, Character_set_results, Character_set_server,

1, Problem: Import Big Data volume to the database, with our ordinary sqlhelper to do is every insert is open connection closed connection, so too slow, so we would like to keep SqlConnection open until all the data is inserted to complete and then

Three paradigms of database designIn order to build a database with small redundancy and reasonable structure, we must follow certain rules when designing database. In a relational database, this rule is called a paradigm. A paradigm is a summary of

The book said a lot, it boils down to 3 words:1NF: field is not divided;2NF: Primary key, non-primary key field depends on primary key;3NF: Non-primary key fields cannot depend on each other;Explain:1NF: Atomic field can not be re-divided, otherwise

Preface: Have been accustomed to use myeclipse automatically generate hibernate, but the manual configuration has been not very understanding, are embarrassed to say that they are engaged in Java. So hurriedly reviewed the manual configuration, and

The default output, the database field name is the key to the array of keys output, but the data with the key is not able to meet the unknown operation, here are a good way to solve this problemThe database operation function encapsulated in the YII

As described in the lock mechanism of a database, the task of concurrency control in a database management system (DBMS) is to ensure that the same data in the database is accessed simultaneously without disrupting the isolation and uniformity of

Python orm is diverse, such as: Django Orm, SQLAlchemy, Sqlobject, today we introduce a compact and lean framework, supported databases: SQLITE,MYSQL,POSTGRESQL, supported Python version: 2.6 + and 3.2+Official documentation Links1. Installing

One, Can ' t connect to the MySQL server on ' localhost ' (10061)? Translation: Can't connect to MySQL on localhost? Analysis: This indicates that the "localhost" computer exists, but does not provide MySQL service on this machine. Need to start

One, what is a database? A database is a warehouse that organizes, stores, and manages data according to data structures, and each database has one or more different APIs for creating, accessing, managing, searching, and replicating the data that

Top J-hi Lookup for cascading drop effects Description : The processing mechanism of lookup in the DWZ version is completely different from that of the classic, there are two manifestations of lookup, one is to bring back the selected value by

About MySQL collation of the need for memory and proficiency in the content 1./* View Operation * *---------------------------------------------------------------------------------------------------- ---1. /* View Operation * * Show

J2ee| e-commerce Summary:In this paper, an example is given to analyze the whole process of using the technology architecture of Java EE to build an enterprise-Class e-commerce website, and to analyze the key parts and related technologies, and to

oracle| Data Oracle Data dictionary Introduction to Oracle Database Dictionaries Oracle data dictionaries consist of tables and views that store some database objects about database structure information. The database dictionary describes how the

Beginner's News | web | Beginner ASP is a good thing, its powerful interaction ability and data processing ability make it become the favorite of the commercial website. However, the design and debugging of ASP programs is not easy, just high-end