How to join 4 or more tables in the database?

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I tried to make a 3 joined taqlbe and did this:

VB

daSector = New OleDbDataAdapter("SELECT Sector.SectorName, Association.AssociationName, Company.CompanyName, Company.CompanyLocation " &
                              "FROM (Sector INNER JOIN Association ON Sector.SectorID=Association.SectorID)" &
                              "INNER JOIN Company ON Company.AssociationID = Association.AssociationID", con)

It worked as I was expecting it to work but when I added another table.
These set codes of sets below.

VB

daSector = New OleDbDataAdapter("SELECT Sector.SectorName, Association.AssociationName, Company.CompanyName, Company.CompanyLocation,Product.ProductDesc,Product.RawMatDesc " & 
                            "FROM (Sector INNER JOIN Association ON Sector.SectorID=Association.SectorID)" & 
                            "(INNER JOIN Company ON Company.AssociationID = Association.AssociationID) " & 
                            " INNER JOIN Product ON Product.CompanyID = Company.CompanyID  ", con)

It stops working and pops out an error that says something is wrong with the FROM clause. So as you can see there, I put the 2nd inner join into parenthesis but still no use and pops out the FROM clause error again. Can someone please point out what am I lacking here?

Posted 19-Jul-15 22:15pm

Jake Robert

Updated 19-Jul-15 22:18pm

Wendelius

v2

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2 solutions

Solution 2

I made it work by coating another parenthesis

VB

daSector = New OleDbDataAdapter("SELECT Sector.SectorName, Association.AssociationName, Company.CompanyName, Company.CompanyLocation, Product.ProductDesc, Product.RawMatDesc " &
"FROM ((Sector " &
"INNER JOIN Association ON Sector.SectorID=Association.SectorID) " &
"INNER JOIN Company ON Association.AssociationID=Company.AssociationID) " &
"INNER JOIN Product ON Company.CompanyID=Product.CompanyID ", con)

Thanks for your suggestion though :) If not for you I would not realize it.

Posted 19-Jul-15 22:43pm

Jake Robert

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Wendelius · Accepted Answer · 2015-07-19T22:22:00

Joining more than two tables is the same as with two tables so you need to have some mistake in the table names, column names or syntax.

Typically the tables are listed in the ON clause in the same order as they are in the FROM clause. Also I don't see any need for the parenthesis.

So simply try something like

SQL

SELECT Sector.SectorName, Association.AssociationName, Company.CompanyName, Company.CompanyLocation,Product.ProductDesc,Product.RawMatDesc 
FROM Sector 
     INNER JOIN Association ON Sector.SectorID=Association.SectorID
     INNER JOIN Company ON Association.AssociationID = Company.AssociationID
     INNER JOIN Product ON Company.CompanyID = Product.CompanyID