Question

出于某种原因，我不断获得带有DISTINCT信息的输出。我想了解JOINS，我不知道为什么我会得到这个输出：

MANUFACTURE                              MODEL         
---------------------------------------- ---------------
Chrysler Corp.                           200            
Ford Motor Company                       300            
General Motors                           200 Convertible
Honda                                    Durango        
Nisan                                    Avenger        
Toyota                                   Town & Country 
                                         4Runner        
                                         Altima         
                                         Caliber        
                                         Camry          
                                         Challenger     
                                         Charger        
                                         Colorado       
                                         Corolla        
                                         Cruze          
                                         EX37           
                                         Grand Caravan  
                                         Journey        
                                         Malibu         
                                         Orlando        
                                         Pathfinder     
                                         Prius          
                                         Q50            
                                         Q60            
                                         Q70            
                                         Rogue SL       
                                         Sonic          
                                         Versa Note     

 28 rows selected

以下是我尝试过以及输出的内容：

SELECT MANUFACTURENAME AS "MANUFACTURE", MODELNAME AS "MODEL"
FROM TBLMANUFACTURE
FULL JOIN TBLMODEL
ON TBLMANUFACTURE.MANUFACTUREID = TBLMODEL.MODELID
ORDER BY MANUFACTURENAME, MODELNAME ASC;

我要做的是列出所有制造商名称及其相关型号。

重写此问题的脚本：

DROP TABLE  tblOptionDetail;
DROP TABLE  tblOption;
DROP TABLE  tblVehicle;
DROP TABLE  tblModel;
DROP TABLE  tblBrand;
DROP TABLE  tblManufacture;


CREATE TABLE tblManufacture
(
ManufactureID NUMBER(38) PRIMARY KEY,
ManufactureName CHAR(40)
);

CREATE TABLE tblBrand
(
BrandID NUMBER(38) PRIMARY KEY,
ManufactureID NUMBER(38),
BrandName CHAR(40),
FOREIGN KEY (ManufactureID) REFERENCES tblManufacture(ManufactureID)
);

CREATE TABLE tblModel
(
ModelID NUMBER(38) PRIMARY KEY,
BrandID NUMBER(38),
ModelName CHAR(40),
FOREIGN KEY (BrandID) REFERENCES tblBrand(BrandID)
);

CREATE TABLE tblVehicle
(
VehicleID NUMBER(38) PRIMARY KEY,
ModelID NUMBER(38),
VehicleYear NUMBER(38) CHECK (VehicleYear BETWEEN 1900 and 3000),
VehicleKM NUMBER(38) CHECK (VehicleKM BETWEEN 0 and 100000000),
VehiclePrice NUMBER(38) CONSTRAINT carprice CHECK (VehiclePrice BETWEEN 0 and 1000000),
FOREIGN KEY (ModelID) REFERENCES tblModel(ModelID)
);

CREATE TABLE tblOption
(
OptionID NUMBER(38) PRIMARY KEY,
OptionDesc CHAR(40)
);

CREATE TABLE tblOptionDetail
(
OptionID NUMBER(38),
VehicleID NUMBER(38),
PRIMARY KEY (OptionID, VehicleID),
FOREIGN KEY (OptionID) REFERENCES tblOption(OptionID),
FOREIGN KEY (VehicleID) REFERENCES tblVehicle(VehicleID)
);


-- populate the Manufacture table

INSERT ALL 
INTO tblManufacture (ManufactureID, ManufactureName) VALUES (1,'Chrysler Corp.')
INTO tblManufacture (ManufactureID, ManufactureName) VALUES(2,'General Motors')
INTO tblManufacture (ManufactureID, ManufactureName) VALUES(3,'Ford Motor Company')
INTO tblManufacture (ManufactureID, ManufactureName) VALUES(4,'Toyota')
INTO tblManufacture (ManufactureID, ManufactureName) VALUES (5,'Honda')
INTO tblManufacture (ManufactureID, ManufactureName) VALUES (6,'Nisan')
SELECT * FROM dual;

-- populate the Brand table

INSERT ALL
INTO tblBrand (BrandID, ManufactureID, BrandName) VALUES (1,1, 'Chrysler')
INTO tblBrand (BrandID, ManufactureID, BrandName) VALUES (2,1, 'Dodge')
INTO tblBrand (BrandID, ManufactureID, BrandName) VALUES (3,1, 'Jeep')
INTO tblBrand (BrandID, ManufactureID, BrandName) VALUES (4,2, 'Chevrolet')
INTO tblBrand (BrandID, ManufactureID, BrandName) VALUES (5,2, 'Buick')
INTO tblBrand (BrandID, ManufactureID, BrandName) VALUES (6,2, 'Cadillac')
INTO tblBrand (BrandID, ManufactureID, BrandName) VALUES (7,2, 'GMC')
INTO tblBrand (BrandID, ManufactureID, BrandName) VALUES (8,4, 'Toyota')
INTO tblBrand (BrandID, ManufactureID, BrandName) VALUES (9,6, 'Nissan')
INTO tblBrand (BrandID, ManufactureID, BrandName) VALUES (10,6,'Infiniti')
SELECT * FROM dual;

-- populate the Model table

INSERT ALL
INTO tblModel (ModelID, BrandID, ModelName) VALUES (1,1, '200')
INTO tblModel (ModelID, BrandID, ModelName) VALUES (2,1, '200 Convertible')
INTO tblModel (ModelID, BrandID, ModelName) VALUES (3,1, '300')
INTO tblModel (ModelID, BrandID, ModelName) VALUES (4,1, 'Town'||' & '||'Country')
INTO tblModel (ModelID, BrandID, ModelName) VALUES (5,2, 'Durango')
INTO tblModel (ModelID, BrandID, ModelName) VALUES (6,2, 'Avenger')
INTO tblModel (ModelID, BrandID, ModelName) VALUES (7,2, 'Challenger')
INTO tblModel (ModelID, BrandID, ModelName) VALUES (8,2, 'Charger')
INTO tblModel (ModelID, BrandID, ModelName) VALUES (9,2, 'Caliber')
INTO tblModel (ModelID, BrandID, ModelName) VALUES (10,2, 'Grand Caravan')
INTO tblModel (ModelID, BrandID, ModelName) VALUES (11,2, 'Journey')
INTO tblModel (ModelID, BrandID, ModelName) VALUES (12,4, 'Sonic')
INTO tblModel (ModelID, BrandID, ModelName) VALUES (13,4, 'Cruze')
INTO tblModel (ModelID, BrandID, ModelName) VALUES (14,4, 'Orlando')
INTO tblModel (ModelID, BrandID, ModelName) VALUES (15,4, 'Colorado')
INTO tblModel (ModelID, BrandID, ModelName) VALUES (16,4, 'Malibu')
INTO tblModel (ModelID, BrandID, ModelName) VALUES (17,8, '4Runner')
INTO tblModel (ModelID, BrandID, ModelName) VALUES (18,8, 'Prius')
INTO tblModel (ModelID, BrandID, ModelName) VALUES  (19,8, 'Camry')
INTO tblModel (ModelID, BrandID, ModelName) VALUES  (20,8, 'Corolla')
INTO tblModel (ModelID, BrandID, ModelName) VALUES (21,9,'Rogue SL')
INTO tblModel (ModelID, BrandID, ModelName) VALUES  (22,9, 'Versa Note')
INTO tblModel (ModelID, BrandID, ModelName) VALUES  (23,9, 'Pathfinder')
INTO tblModel (ModelID, BrandID, ModelName) VALUES  (24,9, 'Altima')
INTO tblModel (ModelID, BrandID, ModelName) VALUES (25,10, 'Q70')
INTO tblModel (ModelID, BrandID, ModelName) VALUES  (26,10, 'Q50')
INTO tblModel (ModelID, BrandID, ModelName) VALUES  (27,10, 'Q60')
INTO tblModel (ModelID, BrandID, ModelName) VALUES  (28,10, 'EX37')
SELECT * FROM dual;

-- populate Option table

INSERT ALL 
INTO tblOption (OptionID,OptionDesc) VALUES (1,'Power locks')
INTO tblOption (OptionID,OptionDesc) VALUES (2,'Power windows')
INTO tblOption (OptionID,OptionDesc) VALUES (3,'Air conditioning')
INTO tblOption (OptionID,OptionDesc) VALUES (4,'Heated mirrors')
INTO tblOption (OptionID,OptionDesc) VALUES (5,'Remote keyless entry')
INTO tblOption (OptionID,OptionDesc) VALUES (6,'CD Player')
INTO tblOption (OptionID,OptionDesc) VALUES (7,'GPS')
INTO tblOption (OptionID,OptionDesc) VALUES (8,'In-dash DVD player')
INTO tblOption (OptionID,OptionDesc) VALUES (9,'Overhead DVD player')
INTO tblOption (OptionID,OptionDesc) VALUES (10,'Satellite radio')
INTO tblOption (OptionID,OptionDesc) VALUES (11,'MP3 player')
INTO tblOption (OptionID,OptionDesc) VALUES (12,'Antilock braking system')
INTO tblOption (OptionID,OptionDesc) VALUES (13,'Electronic stability system')
INTO tblOption (OptionID,OptionDesc) VALUES (14,'Traction control')
INTO tblOption (OptionID,OptionDesc) VALUES (15,'Cruise control')
INTO tblOption (OptionID,OptionDesc) VALUES (16,'Intelligent cruise control')
INTO tblOption (OptionID,OptionDesc) VALUES (17,'Parking assist system')
INTO tblOption (OptionID,OptionDesc) VALUES (18,'Xenon headlights')
INTO tblOption (OptionID,OptionDesc) VALUES (19,'Aluminum rims')
INTO tblOption (OptionID,OptionDesc) VALUES (20,'AWD')
INTO tblOption (OptionID,OptionDesc) VALUES (21,'Convertable')
INTO tblOption (OptionID,OptionDesc) VALUES (22,'Heated Seats')
SELECT * FROM dual;

-- populate Vehicle table

INSERT ALL
INTO tblVehicle (VehicleID,ModelID, VehicleYear, VehicleKM, VehiclePrice) VALUES (1,10, 2010, 45000, 18000)
INTO tblVehicle (VehicleID,ModelID, VehicleYear, VehicleKM, VehiclePrice) VALUES (2,10, 2010, 65420, 17500)
INTO tblVehicle (VehicleID,ModelID, VehicleYear, VehicleKM, VehiclePrice) VALUES (3,16, 2004, 143900, 3200)
INTO tblVehicle (VehicleID,ModelID, VehicleYear, VehicleKM, VehiclePrice) VALUES (4,11, 2010, 38900, 14500)
INTO tblVehicle (VehicleID,ModelID, VehicleYear, VehicleKM, VehiclePrice) VALUES (5,27,2014,17250,45999)
INTO tblVehicle (VehicleID,ModelID, VehicleYear, VehicleKM, VehiclePrice) VALUES (6,25,2015,2900,62300)
INTO tblVehicle (VehicleID,ModelID, VehicleYear, VehicleKM, VehiclePrice) VALUES (7,17,2010,87900,19800)
SELECT * FROM dual;

-- populate OptionDetail table

INSERT ALL
INTO tblOptionDetail (OptionID, VehicleID) VALUES (2, 2)
INTO tblOptionDetail (OptionID, VehicleID) VALUES (1, 2)
INTO tblOptionDetail (OptionID, VehicleID) VALUES (3, 2)
INTO tblOptionDetail (OptionID, VehicleID) VALUES (5, 2)
INTO tblOptionDetail (OptionID, VehicleID) VALUES (6, 2)
INTO tblOptionDetail (OptionID, VehicleID) VALUES (7, 2)
INTO tblOptionDetail (OptionID, VehicleID) VALUES (8, 2)
INTO tblOptionDetail (OptionID, VehicleID) VALUES (11, 2)
INTO tblOptionDetail (OptionID, VehicleID) VALUES (12, 2)
INTO tblOptionDetail (OptionID, VehicleID) VALUES (14, 2)
INTO tblOptionDetail (OptionID, VehicleID) VALUES (15, 2)
INTO tblOptionDetail (OptionID, VehicleID) VALUES (19, 2)
INTO tblOptionDetail (OptionID, VehicleID) VALUES (2, 1)
INTO tblOptionDetail (OptionID, VehicleID) VALUES (1, 1)
INTO tblOptionDetail (OptionID, VehicleID) VALUES (3, 1)
INTO tblOptionDetail (OptionID, VehicleID) VALUES (6, 1)
INTO tblOptionDetail (OptionID, VehicleID) VALUES (12, 1)
INTO tblOptionDetail (OptionID, VehicleID) VALUES (14, 1)
INTO tblOptionDetail (OptionID, VehicleID) VALUES (15, 1)
INTO tblOptionDetail (OptionID, VehicleID) VALUES (19, 1)
INTO tblOptionDetail (OptionID, VehicleID) VALUES (2, 3)
INTO tblOptionDetail (OptionID, VehicleID) VALUES (1, 3)
INTO tblOptionDetail (OptionID, VehicleID) VALUES (3, 3)
INTO tblOptionDetail (OptionID, VehicleID) VALUES (6, 3)
INTO tblOptionDetail (OptionID, VehicleID) VALUES (12, 3)
INTO tblOptionDetail (OptionID, VehicleID) VALUES (14, 3)
INTO tblOptionDetail (OptionID, VehicleID) VALUES (15, 3)
INTO tblOptionDetail (OptionID, VehicleID) VALUES (19, 3)
INTO tblOptionDetail (OptionID, VehicleID) VALUES (2, 4)
INTO tblOptionDetail (OptionID, VehicleID) VALUES (1, 4)
INTO tblOptionDetail (OptionID, VehicleID) VALUES (3, 4)
INTO tblOptionDetail (OptionID, VehicleID) VALUES (6, 4)
INTO tblOptionDetail (OptionID, VehicleID) VALUES (11, 4)
INTO tblOptionDetail (OptionID, VehicleID) VALUES (12, 4)
INTO tblOptionDetail (OptionID, VehicleID) VALUES (14, 4)
INTO tblOptionDetail (OptionID, VehicleID) VALUES (15, 4)
INTO tblOptionDetail (OptionID, VehicleID) VALUES (19, 4)
INTO tblOptionDetail (OptionID, VehicleID) VALUES  (4,5)
INTO tblOptionDetail (OptionID, VehicleID) VALUES (8,5)
INTO tblOptionDetail (OptionID, VehicleID) VALUES (1,5)
INTO tblOptionDetail (OptionID, VehicleID) VALUES (2,5)
INTO tblOptionDetail (OptionID, VehicleID) VALUES (5,5)
INTO tblOptionDetail (OptionID, VehicleID) VALUES (21,6)
INTO tblOptionDetail (OptionID, VehicleID) VALUES (22,6)
INTO tblOptionDetail (OptionID, VehicleID) VALUES (3,6)
INTO tblOptionDetail (OptionID, VehicleID) VALUES (1,6)
INTO tblOptionDetail (OptionID, VehicleID) VALUES (2,6)
INTO tblOptionDetail (OptionID, VehicleID) VALUES (1,7)
INTO tblOptionDetail (OptionID, VehicleID) VALUES (4,7)
INTO tblOptionDetail (OptionID, VehicleID) VALUES (5,7)
INTO tblOptionDetail (OptionID, VehicleID) VALUES (2,7)
SELECT * FROM dual;

COMMIT;

Answer 1

您必须包含tblBrand才能将制造商与模型链接起来。如此规则的内部联接：

SELECT MANUFACTURENAME AS "MANUFACTURE", MODELNAME AS "MODEL"
FROM TBLMANUFACTURE 
join tblBrand ON TBLMANUFACTURE.ManufactureID = tblBrand.ManufactureID 
JOIN TBLMODEL ON tblBrand.BrandID= TBLMODEL.BrandID
ORDER BY MANUFACTURENAME, MODELNAME ASC;

Answer 2

连接条件错误 - 如果model_id与manufacturer_id匹配，为什么要“加入”（考虑“兼容”）模型和制造商？

相反，您需要通过品牌表加入（没有从型号到制造商的直接参考）;在brand_id上加入模型和品牌，然后在manufacturer_id上与制造商进一步加入。

select ma.manufacturename, mo.modelname
from   tblmodel mo join tblbrand       br on mo.brandid = br.brandid
                   join tblmanufacture ma on br.manufactureid = ma.manufactureid
;

Answer 3

嗨，您正在使用完全加入。您的情况基于ON TBLMANUFACTURE.MANUFACTUREID = TBLMODEL.MODELID 即，您正在两个表中的列之间选择匹配数据以及不匹配的列
如果您需要更多的了解，请访问此网站
https://etlinfromatica.wordpress.com/joiner-transformation/
表中的图表对您有帮助

Answer 4

你应该使用＆＃34;品牌＆＃34; brandid表。你可以尝试这段代码;

SELECT manufacturename, modelname
  FROM TBLMANUFACTURE t, tblbrand tt, tblmodel ttt
 where t.manufactureid = tt.manufactureid
   and ttt.brandid = tt.brandid

我希望它可以帮到你。

表格显示DISTINCT信息，当我告诉它不？

4 个答案: