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SQL Language - Linking tables (many to many)

SQL Language - Linking tables (many to many)

SQL Language - Linking tables (many to many)

I have the following tables i want to pull information from

Members - MemID, MemFName, MemLastName
Projects - ProjName, ProjDesc
Expertise - ExpertiseID, ExpertiseDesc
Software - Soft ID, SoftDesc

There is a many to many relationship between
Members - Projects
Members - Expertise
Members - Software

These are "taken care of" by use of bridge entities which hold the primary key of each table:

br_ProjMem -> ProjId, MemID
br_MemExpertise -> MemID, ExpertiseID
br_MemSoft -> MemID, SOftID

Members - br_Memproj - Projects
Members - br_MemExpertise - Expertise
Members - br_MemSoft - Software

Now i have to do queries based on selected criteria (the ids for each table)

for example:

if i could even figure out how to select all the data from each table where the MemID = '21'.... it would be a start.

but when i try even the following sql statement:

SELECT Members.FName, Members.Initial, Members.LName, Members.Title, ECOffices.Region AS Expr1, Members.SpecialityNotes, Members.BuildAdd, ECOffices.Address, ECOffices.City, ECOFfices.Prov AS Expr2, ECOffices.PostCode, Members.phone, Members.fax, Members.email, Software.SoftDesc, Expertise.ExpertiseDesc, Projects.ProjName
FROM ECOffices, Members, Software, Expertise, br_ProjMem, br_MemSoft, br_MemExpertise, Projects

Members.MemID = br_ProjMem.MemID AND
Projects.ProjName = br_ProjMem.ProjName AND

Members.MemID = br_MemExpertise.MemID AND
Expertise.ExpertiseID = br_MemExpertise.ExpertiseID AND

Members.MemID = br_MemSoft.MemID AND
Software.SoftID = br_MemSoft.SoftID AND

ECOffices.OfficeID = Members.OfficeID;

even without supplying any criteria, i get an empty set of records.

how should i write my sql statment so this works out right??



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