Select distinct records on a join

Question

I have two mysql tables - a sales table:

+----------------+------------------------------+------+-----+---------+-------+
| Field          | Type                    


        

Answer 1

YOu had comment about the sales week too. And wanting the most recent week, you may want to try using a GROUP BY

SELECT 
      items.ItemName, 
      items.ItemId,
      max( Sales.SaleWeek ) MostRecentSaleWeek
   FROM 
      items JOIN sales ON items.ItemId = sales.ItemId
   WHERE 
      sales.StoreID = ? 
   GROUP BY
      items.ItemID,
      items.ItemName
   ORDER BY
      MostRecentSaleWeek,   -- ordinal column number 3 via the MAX() call
      items.ItemName

You may have to change the ORDER BY to the ordinal 3rd column reference if you so want based on that column.. This query will give you each distinct item AND the most recent week it was sold.

Answer 2

We can use this:

INSERT INTO `test_table` (`id`, `name`) SELECT DISTINCT 
    a.`employee_id`,b.`first_name` FROM `employee_leave_details`as a INNER JOIN 
    `employee_register` as b ON a.`employee_id` = b.`employee_id`

Answer 3

A DISTINCT should do what you're looking for:

SELECT DISTINCT items.ItemName, items.ItemId FROM items
JOIN sales ON items.ItemId = sales.ItemId 
WHERE sales.StoreID = ? ORDER BY sales.SaleWeek DESC;

That would return only distinct items.ItemName, items.ItemId tuples.

Answer 4

    SELECT  u.user_name,u.user_id, u.user_country,u.user_phone_no,ind.Industry_name,inv.id,u.user_email
    FROM invitations inv
    LEFT JOIN users u
    ON inv.sender_id = u.user_id
    LEFT JOIN employee_info ei
    ON inv.sender_id=ei.employee_fb_id   
    LEFT JOIN industries ind
    ON ei.industry_id=ind.id
    WHERE inv.receiver_id='XXX'
    AND inv.invitation_status='0'
    AND inv.invitati

on_status_desc='PENDING'
GROUP BY (user_id)