SQL 基础篇
一:普通查询语句 :SELECT
语法:
SELECT column1, column2, ... FROM table_name;
或
SELECT * FROM table_name;
示例:
SELECT * FROM Websites; SELECT name,country FROM Websites;
二:去重查询语句 :SELECT DISTINCT
语法:
SELECT column1, column2, ... FROM table_name;
或
SELECT * FROM table_name;
示例:
SELECT * FROM Websites; SELECT name,country FROM Websites;