高级数据过滤

组合WHERE语句

AND操作符

SELECT prod_id, prod_price, prod_name
FROM products
WHERE vend_id  = 'DLL01' AND prod_price <=4;

 

OR操作符

SELECT prod_id, prod_price, prod_name
FROM products
WHERE vend_id  = 'DLL01' OR prod_price <=4;

 

求值顺序

先求AND 再求OR

 

IN操作符

SELECT prod_id, prod_price, prod_name
FROM products
WHERE vend_id IN ('DLL01', 'BRS01');
ORDER BY prod_name;

 

NOT操作符

SELECT prod_id, prod_price, prod_name
FROM products
WHERE  NOT vend_id  IN  = 'DLL01'
ORDER BY prod_name;