database table design best practices

A simple database design example and a simple database design example An example of database design in a simple management system, including design tables, ergraphs, modeling, and scri

The following is an excerpt: If we design the topic table and reply table, the common practice is as follows. In this way, you can directly use the paging algorithm to extract topics when obtaining the topic list. When viewing a post, you also need to link topics and posts to jion. This design defect is:1. The c

Change to a single record of historical data: Common Database Design (2) -- change to a single record of historical data problems 1. Overview There is a type of data stored in the historical customer operation data, such as the bidding documents, the refining scheme list, the price change of the product price, and the change list. Such historical data includes a mainstream water meter that controls the fl

The following extracts are only part of the text:If we were to design a topic table and a reply form, the usual practice would be as follows.This allows you to use the paging algorithm to extract topics when you get a list of topics, and to jion links to topics,posts when you view a post.The disadvantages of this design are:1. Topics

This is my common database user-related design structure - ----table structure ' xxxx_member '-- user table- - CREATE table IF not EXISTS ' xxxx_member ' ( ' uid ' int () unsigned N OT null COMMENT ' user ID ', ' nickname ' char (not null DEFAULT ' COMMENT ' nickname ',

a primary key(because it has no descendants), but must have a foreign key (because it has a father).The design of primary key and foreign key plays an important role in the design of global database. When the global database design is complete, there is an American

the responsibility is still a little unclear, in the Order.addorder (OrderField OrderField) method, There is the product logic inside if (product. Price , of course, here is the business logic is relatively simple case, if the business is more complex, there will be a lot of code in the Order class, in the end, we will find that we have no way of the business architecture is the use of the model to design. We have two

1, table: is the database used to store data to understand the object, is a collection of structured data, is the basis of the entire database system. The concept of everything is abstract, in fact, the table is used to store data.2, the composition of the tableDESC Dept650) this.width=650; "src=" Http://s3.51cto.com/w

Let's take a look at the source code of excellent online programs, analyze the advantages and disadvantages, and quickly improve our level. The following is an excerpt: If we design the topic table and reply table, the common practice is as follows. In this way, you can directly use the paging algorithm to extract Topics when obtaining the topic list. when vi

Let's take a look at the source code of excellent online programs, analyze the advantages and disadvantages, and quickly improve our level. The following is an excerpt: If we design the topic table and reply table, the common practice is as follows. In this way, you can directly use the paging algorithm to extract Topics when obtaining the topic list. when v

Document data table Design In table design, I tried two methods:Use the same entity to represent the sales and purchase orders and other documents, and then identify them by the Document Type field. Because the document is designed to access and exit goods, the document type must have a status sign. The reason for d

derived attributes, and it is necessary to store stored attributes. The attribute that can be null:When there are null values in the database, there may be many situations, which are difficult to process. We need to analyze all the situations. 2. ER model operation and design (1) ER model operation: Includes merging, splitting, adding, deleting, and other operations. (2) The

Chapter 2 Introduction When the data volume is huge, the multi-table is first divided into different databases, and then the data is distributed to different databases according to the key columns. After the database is distributed, the system queries, io, and other operations can all be completed by groups composed of multiple machines. This article focuses on the principles of

index:ALTER table name ENABLE KEYS;7, the principle of design index: The most appropriate column for the index is the column that appears in the WHERE clause, or the column specified in the JOIN clause (ON statement), rather than the column that appears after the select. The greater the number of values in the indexed column, the better the index works. Use a short index: for char and varc