Where clause in Mutiple table sql joins - sql

Question

TABLES
CREATE TABLE LocalBusiness
(
BusinessID INT NOT NULL PRIMARY KEY,
BusinessName VARCHAR2 (20) NOT NULL,
TypeID INT,
Latitude DECIMAL (10,2),
Longitude DECIMAL (10,2),
Web_address VARCHAR2 (50) NOT NULL,
Postcode VARCHAR2 (10) NOT NULL,
official_rating int,
min_price NUMBER(4,2),
max_price NUMBER(4,2),
FOREIGN KEY (TypeID) REFERENCES LocalBusinessType (TypeID),
CONSTRAINT chk_Officialrating CHECK (official_rating> 0 AND official_rating<6 )
);
CREATE TABLE Address
(
AddressID INT NOT NULL PRIMARY KEY,
BusinessID INT,
AreaID INT,
Address VARCHAR2 (50) NOT NULL,
Postcode VARCHAR2 (10) NOT NULL,
FOREIGN KEY (BusinessID) REFERENCES LocalBusiness (BusinessID),
FOREIGN KEY (AreaID) REFERENCES Area (AreaID)
);
CREATE TABLE Phone
(
PhoneNoID INT NOT NULL PRIMARY KEY,
PhoneNo VARCHAR2 (15) NOT NULL,
BusinessID INT,
Description VARCHAR2 (50) NOT NULL,
FOREIGN KEY (BusinessID) REFERENCES LocalBusiness (BusinessID),
CONSTRAINT PhoneNo_unique UNIQUE (PhoneNo)
);
CREATE TABLE Email
(
EmailID INT NOT NULL PRIMARY KEY,
email_address VARCHAR2 (50) NOT NULL,
BusinessID INT,
Description VARCHAR2 (50) NOT NULL,
FOREIGN KEY (BusinessID) REFERENCES LocalBusiness (BusinessID),
CONSTRAINT email_unique UNIQUE (email_address)
);
CREATE TABLE Area
(
AreaID INT NOT NULL PRIMARY KEY,
AreaName VARCHAR2 (20) NOT NULL,
Region VARCHAR2 (20) NOT NULL
);
SELECT statement:
SELECT
LocalBussiness.BusinessName, Address.Address, Address.Postcode,
Area.AreaName, Area.Region, LocalBusiness.OfficialRating,
LocalBusiness.min_price, LocalBusiness_max_price,
Phone.description, Phone.PhoneNo,
Email.Description, Email.email_address,
LocalBusiness.Web_address
FROM
LocalBusiness
JOIN
Address ON LocalBusiness.BusinessID = Address.BusinessID
JOIN
Area ON Address.AreaID = Area.AreaID
AND LocalBusiness.BusinessID = Address.BusinessID
JOIN
Phone ON Phone.BusinessID = LocalBusiness.BusinessID
JOIN
Email ON Email.BusinessID = LocalBusiness.BusinessID
WHERE
TypeID = '1'
ORDER BY
LocalBusiness.BusinessName ASC;
The where clause in the sql join statement written above seem to be ineffective as the some values for the TypeID return incomplete data while others return no rows at all. How do I go about fixing this?

Answer 1

Yyou repeat a condition
AND LocalBusiness.BusinessID=Address.BusinessID in JOIN Area
Try avoinding this repetition
SELECT LocalBussiness.BusinessName, Address.Address, Address.Postcode,
Area.AreaName, Area.Region, LocalBusiness.OfficialRating,
LocalBusiness.min_price, LocalBusiness_max_price, Phone.description,
Phone.PhoneNo, Email.Description, Email.email_address,
LocalBusiness.Web_address
FROM LocalBusiness
JOIN Address ON LocalBusiness.BusinessID=Address.BusinessID
JOIN Area ON Address.AreaID=Area.AreaID
JOIN Phone ON Phone.BusinessID=LocalBusiness.BusinessID
JOIN Email ON Email.BusinessID=LocalBusiness.BusinessID
WHERE TypeID = '1'
ORDER BY LocalBusiness.BusinessName ASC;
Otherwise check th consistence of your data ..