Database
  • Introduction
  • Chapter1: MySQL
    • 1.1. MySQL在Max OSX上的筆記
      • 1.1.1.安裝My SQL (Mac OS X)
      • 1.1.2.My SQL在Mac上的一些warning message
        • 1.1.2.1.更改密碼
    • 1.2.MySQL for Beginners
      • 1.2.1.Getting the Development Environment Ready
        • 1.2.1.1.Windows console
      • 1.2.2.Beginning with MySQL Basics
        • 1.2.2.1.Creating a Database - CREATE DATABASE
        • 1.2.2.2.Creating a Table - CREATE TABLE
        • 1.2.2.3.Inserting Values into Table - INSERT INTO
        • 1.2.2.4.Retrieving Values from Table - SELECT
        • 1.2.2.5.Selecting Distinct Values from Column - DISTINCT
        • 1.2.2.6.Selecting a Specific Data using WHERE Clause
        • 1.2.2.7.Selecting with Multiple Identifiers Using AND
        • 1.2.2.8.Selecting with One of Many Identifiers Using OR
        • 1.2.2.9.Sorting the Data Using ORDER BY
        • 1.2.2.10.Limiting the Data Retrieved Using LIMIT
        • 1.2.2.11.Updating or Modifying Data in a Table Using UPDATE
        • 1.2.2.12.Deleting a Data from a Table Using DELETE
        • 1.2.2.13.Copy table
        • 1.2.2.14.Deleting a Table - DROP TABLE
        • 1.2.2.15.Deleting all values in Table - TRUNCATE TABLE
        • 1.2.2.16.Altering Table Structure - ALTER TABLE
      • 1.2.3.Time to Jump in for More
        • 1.2.3.1.Selecting Data with a Range - BETWEEN
        • 1.2.3.2.Creating Alias Name for a Column - AS
        • 1.2.3.3.Selecting Data which has one of Multitple Values - IN
        • 1.2.3.4.Using LIKE and WILDCARDS
        • 1.2.3.5.Copy Table with INSERT INTO SELECT
        • 1.2.3.6.Combine the Tables - UNION
      • 1.2.4.Few things that Keeps the Database in Shape
        • 1.2.4.1.Primary key
        • 1.2.4.2.Unique key
        • 1.2.4.3.Foreign key
        • 1.2.4.4.Default value
      • 1.2.5.Using Joins to Combine Tables
        • 1.2.5.1.Inner join
        • 1.2.5.2.Left join
        • 1.2.5.3.Right join
        • 1.2.5.4.Full join
  • Chapter2: MongoDB
  • Chapter3: SQL Server
    • 3.1.Obtain Query Execution Plan
    • 3.2.BCP
    • 3.3.SQL操作
      • 3.3.1.取代欄位, 更改欄位中的值
    • 3.4.產生create或drop database/table的script
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  1. Chapter1: MySQL
  2. 1.2.MySQL for Beginners
  3. 1.2.4.Few things that Keeps the Database in Shape

1.2.4.3.Foreign key

  • 指向別的table的primary key

  • 如果有別的table的欄位設定為此table為Foreign key, 則無法被刪除

    • 需要先刪除參考此table為Foreign key的table

Create table studentsbackup2 (id INT(11) auto_increment primary key, coursename VARCHAR(100) not null, student_id INT(11), foreign key (student_id) references studentsdetails(id));
Previous1.2.4.2.Unique keyNext1.2.4.4.Default value

Last updated 5 years ago

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