SQL Multiple Join Statement

MySQL Multiple Joins in one query?

You can simply add another join like this:

SELECT dashboard_data.headline, dashboard_data.message, dashboard_messages.image_id, images.filename
FROM dashboard_data 
    INNER JOIN dashboard_messages 
        ON dashboard_message_id = dashboard_messages.id
    INNER JOIN images
        ON dashboard_messages.image_id = images.image_id 

However be aware that, because it is an INNER JOIN, if you have a message without an image, the entire row will be skipped. If this is a possibility, you may want to do a LEFT OUTER JOIN which will return all your dashboard messages and an image_filename only if one exists (otherwise you'll get a null)

SELECT dashboard_data.headline, dashboard_data.message, dashboard_messages.image_id, images.filename
FROM dashboard_data 
    INNER JOIN dashboard_messages 
        ON dashboard_message_id = dashboard_messages.id
    LEFT OUTER JOIN images
        ON dashboard_messages.image_id = images.image_id 

SQL Multiple INNER JOINS In One Select-Statement

You want to summarize across different "dimensions" -- that is tables. One good approach is to aggregate before doing the JOINs. Or to use subqueries. Here is the latter approach:

SELECT pm.prod_id, pm.prod_name, 
       (SELECT SUM(ed.prod_qty)
        FROM estimatedetailstb as ed
        WHERE ed.prodid = ed.prodidas
       ) as Est_qty,
       (SELECT SUM(sd.prod_qty)
        FROM salesdetailstb as sd
        WHERE sd.prodid = pm.prodidas
       ) as Sales_qty,
       (SELECT SUM(pd.prod_qty)
        FROM purchasedetailstb as pd
        WHERE pd.prodid = pm.prodid
       ) as Sales_qty
FROM productmaster pm;

This will give you all products, even those missing from one or more of the other tables.

SQL multiple join statement

For multi-table joins, you have to nest the extra joins in brackets:

SELECT ...
FROM ((origintable
JOIN jointable1 ON ...)
JOIN jointable2 ON ...)
JOIN jointable3 ON ...

basically, for every extra table you join past the first, you need a bracket before the original 'FROM' table, and a closing bracket on the matching JOIN 'on' clause.

case statement in sql with multiple joins

A simpler approach

select a, b, table_one.c, d, e
     , table_three.other_column is not null as flag
from table_one inner join table_two on table_one.d = table_two.c
     left join table_three on -- put here the relation rules between table_three
                              -- and the other tables

Case Statement With Multiple Joins

I think the most direct way to represent what you're asking for is:

select coalesce(l2.city, l1.city, '0') as city
  From           emp r
       left join location l1
              on l1.eid = r.eid
             and l1.type=1
       left join location l2
              on l2.eid = r.eid
             and l2.type=2

The subquery-based solution proposed by Jeremy Real may also work, but it assumes that 1 and 2 are they only values in the table for location.type (and I just don't find it to be as intuitive).

SQL query with multiple joins (And Exists?)

You will want to add a NOT EXISTS clause to your query, and remove the LEFT JOIN to your ConditionalCheck table, since you're not actually doing anything with the data there:

Select      A.Column1, A.Column2, B.Column1, IsNull(D.Column1, '')
From        User            A  With (NoLock) 
Inner Join  UserDetails     B  With (NoLock)    On  (B.id = A.id)
Left Join   UserData        C  With (NoLock)    On  (C.uid = B.uid)
Left Join   MoreData        D  With (NoLock)    On  (D.id = A.id)
Where       A.Column1 = 'ABC' 
And Not Exists
(
    Select  *
    From    ConditionalCheck    CC
    Where   CC.S_id = B.S_id
    And     CC.T_id In (2,3)
)

As a side note, for the context of the query provided, the LEFT JOIN to the UserData table is also unnecessary.

IBM DB2: SQL query with multiple Join

The issue is probably due to the below clause:

INNER JOIN ICMADMIN.table_002 ON INDEX_NOREL = A.INDEX_NOREL

Here INDEX_NOREL on the left side is not accompanied by any table alias. Since ICMADMIN.table_001 and ICMADMIN.table_002 both have the column named INDEX_NOREL, that is why you are facing this issue. Just create an alias for ICMADMIN.table_002 and accompany INDEX_NOREL by that alias it will work.

   FROM ICMADMIN.table_001 A
    INNER JOIN ICMADMIN.table_002 C ON C.INDEX_NOREL = A.INDEX_NOREL 

presto sql: multiple join with `using` statement

Your two versions are functionally equivalent (except for the obvious difference of a duplicated user_id column when not using using). The first inner join mandates that the two user_ids have the same value, so either comparison returns the same result set.

If you had a series of left joins then you would be requiring that the value be in the first table, and the equivalent would be t1.user_id.

If you had full joins, then you would not know. The matching would be from the table that has a value on the row. If both tables have a value, the logic says that they are the same, so it doesn't make a difference.

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