I have a table like:
Table1
And I need to add a column to that table as average delivery time
avr_del_time column added
My code is:
SELECT a.vendor, a.part_nr, a.delivery_time, b.avr_del_time
FROM Table1 a
INNER JOIN (SELECT AVG(delivery_time) AS avr_del_time FROM Table1 GROUP BY vendor, part_nr) b
ON a.vendor = b.vendor, a.part_nr=b.part_nr
please guide me...
Your query is on the right track. You just need to fix up the SQL mistakes:
SELECT a.vendor, a.part_nr, a.delivery_time, b.avr_del_time
FROM Table1 as a INNER JOIN
(SELECT vendor, part_nr, AVG(delivery_time) AS avr_del_time
FROM Table1
GROUP BY vendor, part_nr
) as b
ON a.vendor = b.vendor AND a.part_nr = b.part_nr;
Notes:
In the GROUP BY subquery, you need the keys in the SELECT.
You have a comma in the ON condition; it should be AND.
I would suggest that you use table aliases that are abbreviations for the table names.
Don't see any issue with your posted code except the JOIN ON condition which should
ON a.vendor = b.vendor
AND a.part_nr=b.part_nr // OR condition can as well be based on requirement
Also since it's a computed value, no point in adding a separate column to your table rather have that column in your display result while fetching from table
You need to return the joined fields in the subquery or the join won't work
SELECT a.vendor, a.part_nr, a.delivery_time, b.avr_del_time
FROM Table1 a
INNER JOIN (SELECT Vendor,
part_nr,
AVG(delivery_time) AS avr_del_time
FROM Table1
GROUP BY vendor, part_nr) b
ON a.vendor = b.vendor and a.part_nr=b.part_nr
Related
i have following sql in java project:
select distinct * from drivers inner join licenses on drivers.user_id=licenses.issuer_id
inner join users on drivers.user_id=users.id
where (licenses.state='ISSUED' or drivers.status='WAITING')
and users.is_deleted=false
And result i database looks like this:
And i would like to get only one result instead of two duplicated results.
How can i do that?
Solution 1 - That's Because one of data has duplicate value write distinct keyword with only column you want like this
Select distinct id, distinct creation_date, distinct modification_date from
YourTable
Solution 2 - apply distinct only on ID and once you get id you can get all data using in query
select * from yourtable where id in (select distinct id from drivers inner join
licenses
on drivers.user_id=licenses.issuer_id
inner join users on drivers.user_id=users.id
where (licenses.state='ISSUED' or drivers.status='WAITING')
and users.is_deleted=false )
Enum fields name on select, using COALESCE for fields which value is null.
usually you dont query distinct with * (all columns), because it means if one column has the same value but the rest isn't, it will be treated as a different rows. so you have to distinct only the column you want to, then get the data
I suspect that you want left joins like this:
select *
from users u left join
drivers d
on d.user_id = u.id and d.status = 'WAITING' left join
licenses l
on d.user_id = l.issuer_id and l.state = 'ISSUED'
where u.is_deleted = false and
(d.user_id is not null or l.issuer_id is not null);
I'm joining these three tables, but the same information gets displayed 3 times ... Any idea how to have only the unique rows to be displayed, as determined by unique shipment id's?
SELECT S.SHIPMENT_ID, S.CREATION_DATE, S.BUSINESS_ID, B.BUS_ID, S.SHIPMENT_STATUS, S.BUSINESS_NAME, S.SHIPMENT_MODES, S.CUSTOMER_NAME
FROM "SHIPMENT" S
INNER JOIN "BUSINESS" B ON S.BUSINESS_ID=B.BUS_ID
INNER JOIN "SHIPMENT_GROUP" SG ON S.SHIPMENT_ID=SG.SHIPMENT_ID
INNER JOIN "DATA_GROUP" DG ON DG.ID=SG.GROUP_ID
try select distinct
SELECT DISTINCT column1, column2, ...
FROM table_name;
w3schools
You are selecting rows from the first table only, so this suggests that you are using the joins for filtering.
If so, you can rewrite this with exists, which will avoid duplicates if there are multiple matches. Starting from your existing query, the logic would be:
select s.*
from shipment s
where
exists (
select 1
from business b
where b.bus_id = s.business_id
) and exists (
select 1
from shipment_group sg
inner join data_group dg on dg.id = sg.group_id
where sg.shipment_id = s.shipment_id
)
SELECT tblT.Tick, First(tblB.BDF) AS FirstOfBDF
FROM tblT INNER JOIN tblB ON tblT.Tick = tblB.Tick
GROUP BY tblT.Tick;
My Access table (tblB) is sorted by Tick and then by BDF. How come it does not retrieve the correct data?
There is no guarantee that table is sorted unless you explicitly mention Order by.
select top 1 tblT.Tick, First(tblB.BDF) AS FirstOfBDF
from FROM tblT INNER JOIN tblB ON tblT.Tick = tblB.Tick
GROUP BY tblT.Tick
Order by tblt.Tick ;
I have two tables in SQL Server, tbl_disputes and tbl_disputetypes. The tbl_disputes table contains a foreign key column disputetype. The table tbl_disputetypes contains the primary key field disputetypeid and disputetypedesc. The following query gives me a count of each disputetype from the tbl_disputes table.
select disputetype, count(disputetype) as numberof
from tbl_disputes
group by disputetype
What sort of join or subquery do I need to use to display the
tbl_disputetypes.dbo.disputetypedesc instead of tbl_disputes.dbo.disputetype?
EDIT Issue was because disputetypedesc was set as TEXT. I changed it to nvarchar, and the following query worked:
SELECT
tbl_disputetypes.disputetypedesc,
count(tbl_disputetypes.disputetypedesc)
FROM
tbl_disputes Left OUTER JOIN
tbl_disputetypes ON tbl_disputes.disputetype = tbl_disputetypes.disputetypeid
group by tbl_disputetypes.disputetypedesc
Unless I'm missing something, you can just LEFT JOIN the description:
select disputetypedesc, count(disputetype) as numberof
from tbl_disputes d
LEFT JOIN tbl_disputetypes dt
ON dt.disputetypeid = d.disputetype
group by disputetypedesc
Assuming 2005+:
WITH x(t, numberof) AS
(
SELECT disputetype, COUNT(*)
FROM tbl_disputes
GROUP BY disputetype
)
SELECT dt.disputetypedesc, x.numberof
FROM tbl_disputetypes AS dt
INNER JOIN x ON dt.disputetype = x.t;
A simple JOIN?
select
DT.disputetypedesc, count(*) as numberof
from
tbl_disputes D
JOIN
tbl_disputetypes DT ON D.disputetype = DT.disputetype
group by
DT.disputetypedesc
The basic idea is that you will need a sub-query. Something like this will work:
select disputetypedesc, disputetype, numberof
from (select disputetype, count(disputetype) numberof
from tbl_disputes
group by disputetype) t left outer join
tbl_disputetypes on t.disputetype = tbl_disputetypes.disputetype
I am not sure if I understand your question however you should be able to select all columns using a query similar to the code sample below.
The following query will join the two tables by the disputetypeid column. I changed the format of the SQL statement however you can obviously format it however you would like.
SELECT tbl_disputetypes.disputetypedesc
, tbl_disputes.*
, <any_column_from_either_table>
FROM tbl_disputes
INNER JOIN tbl_disputetypes
ON tbl_disputes.disputetypeid = tbl_disputetypes.disputetypeid
I have 3 tables, where the first one's primary key, is the foreign key in the other 2.
I want to extract one field from the first table, and then a count from the other 2, all joined using the pk and fk. This is what I have so far:
SELECT MBDDX_STUDY.STUDY_NAME, COUNT(MBDDX_EXPERIMENT.STUDY_ID) AS NUMBER_OF_EXPERIMENTS
FROM MBDDX_STUDY
INNER JOIN MBDDX_EXPERIMENT
ON MBDDX_STUDY.ID=MBDDX_EXPERIMENT.STUDY_ID
INNER JOIN (SELECT COUNT(MBDDX_TREATMENT_GROUP.GROUP_NO) AS NUMBER_OF_GROUPS
FROM MBDDX_TREATMENT_GROUP)
ON MBDDX_TREATMENT_GROUP.STUDY_ID = MBDDX_STUDY.ID
group by MBDDX_STUDY.STUDY_NAME, MBDDX_TREATMENT_GROUP.STUDY_ID
But, i get an error saying that the MBDDX_TREATMENT_GROUP.STUDY_ID , in the penultimate line is an invalid indentifier. It is a correct table.
Any advise please.
Thanks.
You're getting the error because that column is not in your SELECT, so it can't GROUP BY a field it doesn't have.
The subquery syntax doesn't seem to make any sense to me. You've made a query that counts all rows of MBDDX_TREATMENT_GROUP, independently of the STUDY_ID, and then tries to join it into the table with a join condition that doesn't refer to anything in the subquery's results (and can't, without an alias).
Why not use a simple join? Assuming MBDDX_EXPERIMENT also has a primary key ID, you can do it with a COUNT-DISTINCT:
SELECT
MBDDX_STUDY.ID, MBDDX_STUDY.STUDY_NAME,
COUNT(DISTINCT MBDDX_EXPERIMENT.ID) AS NUMBER_OF_EXPERIMENTS
COUNT(DISTINCT MBDDX_TREATMENT_GROUP.GROUP_NO) AS NUMBER_OF_GROUPS
FROM
MBDDX_STUDY
INNER JOIN MBDDX_EXPERIMENT ON MBDDX_EXPERIMENT.STUDY_ID=MBDDX_STUDY.ID
INNER JOIN MBDDX_TREATMENT_GROUP ON MBDDX_TREATMENT_GROUP.STUDY_ID=MBDDX_STUDY.ID
GROUP BY
MBDDX_STUDY.ID, MBDDX_STUDY.STUDY_NAME
(MBDDX_STUDY.STUDY_NAME technically shouldn't be necessary to include in the GROUP BY expression according to ANSI SQL as it has a functional dependency on STUDY_ID. However it is necessary on Oracle, which can't spot the dependency.)
You don't need to group by this field (MBDDX_TREATMENT_GROUP.STUDY_ID). It should be just group by MBDDX_STUDY.STUDY_NAME
If my understanding is correct,You need a record from first table and have the count of related records in the other two tables.Here is the answer
SQL:Getting count from many tables for a user record in USER table.Whats the best approach?
It looks like you need to alias the second subquery and need to include something to join on.
It also looks like you aren't using the count you have in the subquery as well.
Try this out:
SELECT MBDDX_STUDY.STUDY_NAME
, COUNT(MBDDX_EXPERIMENT.STUDY_ID) AS NUMBER_OF_EXPERIMENTS
FROM MBDDX_STUDY
INNER JOIN MBDDX_EXPERIMENT
ON MBDDX_STUDY.ID=MBDDX_EXPERIMENT.STUDY_ID
INNER JOIN (SELECT STUDY_ID, COUNT(MBDDX_TREATMENT_GROUP.GROUP_NO) AS NUMBER_OF_GROUPS
FROM MBDDX_TREATMENT_GROUP GROUP BY MBDDX_TREATMENT_GROUP.STUDY_ID) xx
ON xx.STUDY_ID = MBDDX_STUDY.ID
GROUP BY MBDDX_STUDY.STUDY_NAME, xx.STUDY_ID
For what you really want to do, you want OUTER JOINs.
WITH number_of_experiments
AS ( SELECT study_id
, count ( * ) CNT
FROM MBDDX_EXPERIMENT
group by study_id )
, number_of_groups
as ( select study_id
, count ( * ) CNT
FROM mbddx_treatment_group
group by study_id )
select study_name
, coalesce(noex.cnt,0)
, coalesce(notr.cnt,0)
from mbddx_study
outer join number_of_experiments
as noex
using ( study_id )
outer join number_of_groups
as nogr
using ( study_id )