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         SQL in MySQL培訓(xùn)

Relational database models
Relational operators
Characteristics of declarative SQL language
SQL syntax
Division language DQL, DML, DDL, DCL
Data Query Language
SELECT queries.
Aliases columns of tables
Service date (DATE types, display functions, formatting)
Group Features
Combining internal and external tables (JOIN clause)
UNION operator
Nested Subqueries (the WHERE clause, the table name, column name)
Correlated subqueries
Data Modification Language
Inserting rows (INSERT clause)
Inserting rows by request
Variation of the rows (UPDATE)
Delete rows (DELETE)
Data Definition Language
Creating, altering and dropping objects (CREATE, ALTER, DROP)
Creating tables using subquery (CREATE TABLE .... AS SELECT...)
CONSTRAINTS
Options NULL and NOT NULL
CONSTRAINT clause
ENUM type
type SET
PRIMARY KEY condition
UNIQUE condition
FOREIGN KEY condition
DEFAULT clause
Transactions
The command COMMIT, ROLLBACK, SAVEPOINT