实例 SQL 比较运算符小于 <

 
SELECT * FROM ProductsWHERE Price < 30;                    

输出结果

ProductID	ProductName	SupplierID	CategoryID	QuantityPerUnit	Price	UnitsInStock	UnitsOnOrder	ReorderLevel	Discontinued
1	Chai	1	1	10 boxes x 20 bags	18.0000	39	0	10	False
2	Chang	1	1	24 - 12 oz bottles	19.0000	17	40	25	False
3	Aniseed Syrup	1	2	12 - 550 ml bottles	10.0000	13	70	25	False
4	Chef Anton's Cajun Seasoning	2	2	48 - 6 oz jars	22.0000	53	0	0	False
5	Chef Anton's Gumbo Mix	2	2	36 boxes	21.3500	0	0	0	True
6	Grandma's Boysenberry Spread	3	2	12 - 8 oz jars	25.0000	120	0	25	False
11	Queso Cabrales	5	4	1 kg pkg.	21.0000	22	30	30	False
13	Konbu	6	8	2 kg box	6.0000	24	0	5	False
14	Tofu	6	7	40 - 100 g pkgs.	23.2500	35	0	0	False
15	Genen Shouyu	6	2	24 - 250 ml bottles	15.5000	39	0	5	False
16	Pavlova	7	3	32 - 500 g boxes	17.4500	29	0	10	False
19	Teatime Chocolate Biscuits	8	3	10 boxes x 12 pieces	9.2000	25	0	5	False
21	Sir Rodney's Scones	8	3	24 pkgs. x 4 pieces	10.0000	3	40	5	False
22	Gustaf's Kn?ckebr?d	9	5	24 - 500 g pkgs.	21.0000	104	0	25	False
23	Tunnbr?d	9	5	12 - 250 g pkgs.	9.0000	61	0	25	False
24	Guaraná Fantástica	10	1	12 - 355 ml cans	4.5000	20	0	0	True
25	NuNuCa Nu?-Nougat-Creme	11	3	20 - 450 g glasses	14.0000	76	0	30	False
30	Nord-Ost Matjeshering	13	8	10 - 200 g glasses	25.8900	10	0	15	False
31	Gorgonzola Telino	14	4	12 - 100 g pkgs	12.5000	0	70	20	False
33	Geitost	15	4	500 g	2.5000	112	0	20	False
34	Sasquatch Ale	16	1	24 - 12 oz bottles	14.0000	111	0	15	False
35	Steeleye Stout	16	1	24 - 12 oz bottles	18.0000	20	0	15	False
36	Inlagd Sill	17	8	24 - 250 g jars	19.0000	112	0	20	False
37	Gravad lax	17	8	12 - 500 g pkgs.	26.0000	11	50	25	False
39	Chartreuse verte	18	1	750 cc per bottle	18.0000	69	0	5	False
40	Boston Crab Meat	19	8	24 - 4 oz tins	18.4000	123	0	30	False
41	Jack's New England Clam Chowder	19	8	12 - 12 oz cans	9.6500	85	0	10	False
42	Singaporean Hokkien Fried Mee	20	5	32 - 1 kg pkgs.	14.0000	26	0	0	True
44	Gula Malacca	20	2	20 - 2 kg bags	19.4500	27	0	15	False
45	Rogede sild	21	8	1k pkg.	9.5000	5	70	15	False
46	Spegesild	21	8	4 - 450 g glasses	12.0000	95	0	0	False
47	Zaanse koeken	22	3	10 - 4 oz boxes	9.5000	36	0	0	False
48	Chocolade	22	3	10 pkgs.	12.7500	15	70	25	False
49	Maxilaku	23	3	24 - 50 g pkgs.	20.0000	10	60	15	False
50	Valkoinen suklaa	23	3	12 - 100 g bars	16.2500	65	0	30	False
52	Filo Mix	24	5	16 - 2 kg boxes	7.0000	38	0	25	False
54	Tourtière	25	6	16 pies	7.4500	21	0	10	False
55	Paté chinois	25	6	24 boxes x 2 pies	24.0000	115	0	20	False
57	Ravioli Angelo	26	5	24 - 250 g pkgs.	19.5000	36	0	20	False
58	Escargots de Bourgogne	27	8	24 pieces	13.2500	62	0	20	False
61	Sirop d'érable	29	2	24 - 500 ml bottles	28.5000	113	0	25	False
65	Louisiana Fiery Hot Pepper Sauce	2	2	32 - 8 oz bottles	21.0500	76	0	0	False
66	Louisiana Hot Spiced Okra	2	2	24 - 8 oz jars	17.0000	4	100	20	False
67	Laughing Lumberjack Lager	16	1	24 - 12 oz bottles	14.0000	52	0	10	False
68	Scottish Longbreads	8	3	10 boxes x 8 pieces	12.5000	6	10	15	False
70	Outback Lager	7	1	24 - 355 ml bottles	15.0000	15	10	30	False
71	Flotemysost	15	4	10 - 500 g pkgs.	21.5000	26	0	0	False
73	R?d Kaviar	17	8	24 - 150 g jars	15.0000	101	0	5	False
74	Longlife Tofu	4	7	5 kg pkg.	10.0000	4	20	5	False
75	Rh?nbr?u Klosterbier	12	1	24 - 0.5 l bottles	7.7500	125	0	25	False
76	Lakkalik??ri	23	1	500 ml	18.0000	57	0	20	False
77	Original Frankfurter grüne So?e	12	2	12 boxes	13.0000	32	0	15	False

参考手册

实例 SQL 比较运算符小于 <

输出结果