计算联接中选择的结果

Question

I have this query that works as I need. However I would like to have a column showing number of times a record repeats.

The query:

SELECT total.Total, subqry.Company AS Supplier, company.Company AS Customer, purchase_details.CompanyID, 
                            product.Description1, purchase_details.PurchaseID, purchase_details.PurchaseCreated, 
                            purchase_details.Completed, purchase_details.OriginalOrd
                    FROM purchase_details
                        LEFT JOIN product ON purchase_details.PartNumber = product.PartNumber
                        LEFT JOIN orders ON purchase_details.OriginalOrd = orders.OrderID
                        LEFT JOIN contact ON orders.ContactLinkID = contact.ID
                        LEFT JOIN company ON contact.LinkID = company.LinkID
                        LEFT JOIN (SELECT company.Company, purchase_details.CompanyID FROM company 
                                    LEFT JOIN purchase_details ON company.ID = purchase_details.CompanyID) 
                                    AS subqry ON purchase_details.CompanyID = subqry.CompanyID
                        LEFT JOIN (SELECT OriginalOrd, count(DISTINCT CompanyID) AS Total FROM purchase_details
                                    GROUP BY OriginalOrd) AS total ON purchase_details.OriginalOrd = total.OriginalOrd
                    WHERE purchase_details.Completed = $show AND
                        (subqry.Company LIKE :search
                        OR company.Company LIKE :search
                        OR product.Description1 LIKE :search
                        OR purchase_details.PartNumber LIKE :search
                        OR purchase_details.PurchaseID LIKE :search
                        OR purchase_details.OriginalOrd LIKE :search)
                    GROUP BY PurchaseID

The company id column returns:

504
1739
504
1389
504

I would like to return the info below so ideally in a join:

504    |   3
1739   |   1
504    |   3
1389   |   1
504    |   3

I will use this column in the php application to trigger other functions.

Thanks in advance

Answer 1

use group by company_id

select count(company_id) as c
from table_name
group by company_id;

Answer 2

Add company_id to the GROUp BY list after PurchaseID and add another column count(DISTINCT company_id) company_count to the select.

SELECT
....//other columns
count(DISTINCT purchase_details.CompanyID) company_count
FROM
...//rest of queries
GROUP BY purchase_details.CompanyID,PurchaseID
;

Answer 3

This bit looks odd...

   SELECT c.Company
        , pd.CompanyID 
     FROM company c
     LEFT 
     JOIN purchase_details pd
       ON c.ID = pd.CompanyID

You're selecting no information from purchase_details that's not already present in company. So why bother?

Also, what might ":search" actually look like?