I'm in need of some assistance. I have search and not found what I'm looking for. I have an assigment for school that requires me to use SQL. I have a query that pulls some colunms from two tables:
SELECT Course.CourseNo, Course.CrHrs, Sections.Yr, Sections.Term, Sections.Location
FROM Course
INNER JOIN Sections ON Course.CourseNo = Sections.CourseNo
WHERE Sections.Term="spring";
I need to add a Totals row at the bottom to count the CourseNo and Sum the CrHrs. It has to be done through SQL query design as I need to paste the code. I know it can be done with the datasheet view but she will not accept that. Any advice?
To accomplish this, you can union your query together with an aggregation query. Its not clear from your question which columns you are trying to get "Totals" from, but here's an example of what I mean using your query and getting counts of each (kind of useless example - but you should be able to apply to what you are doing):
SELECT
[Course].[CourseNo]
, [Course].[CrHrs]
, [Sections].[Yr]
, [Sections].[Term]
, [Sections].[Location]
FROM
[Course]
INNER JOIN [Sections] ON [Course].[CourseNo] = [Sections].[CourseNo]
WHERE [Sections].[Term] = [spring]
UNION ALL
SELECT
"TOTALS"
, SUM([Course].[CrHrs])
, count([Sections].[Yr])
, Count([Sections].[Term])
, Count([Sections].[Location])
FROM
[Course]
INNER JOIN [Sections] ON [Course].[CourseNo] = [Sections].[CourseNo]
WHERE [Sections].[Term] = “spring”
You can prepare your "total" query separately, and then output both query results together with "UNION".
It might look like:
SELECT Course.CourseNo, Course.CrHrs, Sections.Yr, Sections.Term, Sections.Location
FROM Course
INNER JOIN Sections ON Course.CourseNo = Sections.CourseNo
WHERE Sections.Term="spring"
UNION
SELECT "Total", SUM(Course.CrHrs), SUM(Sections.Yr), SUM(Sections.Term), SUM(Sections.Location)
FROM Course
INNER JOIN Sections ON Course.CourseNo = Sections.CourseNo
WHERE Sections.Term="spring";
Whilst you can certainly union the aggregated totals query to the end of your original query, in my opinion this would be really bad practice and would be undesirable for any real-world application.
Consider that the resulting query could no longer be used for any meaningful analysis of the data: if displayed in a datagrid, the user would not be able to sort the data without the totals row being interspersed amongst the rest of the data; the user could no longer use the built-in Totals option to perform their own aggregate operation, and the insertion of a row only identifiable by the term totals could even conflict with other data within the set.
Instead, I would suggest displaying the totals within an entirely separate form control, using a separate query such as the following (based on your own example):
SELECT Count(Course.CourseNo) as Courses, Sum(Course.CrHrs) as Hours
FROM Course INNER JOIN Sections ON Course.CourseNo = Sections.CourseNo
WHERE Sections.Term = "spring";
However, since CrHrs are fields within your Course table and not within your Sections table, the above may yield multiples of the desired result, with the number of hours multiplied by the number of corresponding records in the Sections table.
If this is the case, the following may be more suitable:
SELECT Count(Course.CourseNo) as Courses, Sum(Course.CrHrs) as Hours
FROM
Course INNER JOIN
(SELECT DISTINCT s.CourseNo FROM Sections s WHERE s.Term = "spring") q
ON Course.CourseNo = q.CourseNo
Related
I read many threads but didn't get the right solution to my problem. It's comparable to this Thread
I have a query, which gathers data and writes it per shell script into a csv file:
SELECT
'"Dose History ID"' = d.dhs_id,
'"TxFieldPoint ID"' = tp.tfp_id,
'"TxFieldPointHistory ID"' = tph.tph_id,
...
FROM txfield t
LEFT JOIN txfielpoint tp ON t.fld_id = tp.fld_id
LEFT JOIN txfieldpoint_hst tph ON fh.fhs_id = tph.fhs_id
...
WHERE d.dhs_id NOT IN ('1000', '10000')
AND ...
ORDER BY d.datetime,...;
This is based on an very big database with lots of tables and machine values. I picked my columns of interest and linked them by their built-in table IDs. Now I have to reduce my result where I get many rows with same values and just the IDs are changed. I just need one(first) row of "tph.tph_id" with the mechanics like
WHERE "Rownumber" is 1
or something like this. So far i couldn't implement a proper subquery or use the ROW_NUMBER() SQL function. Your help would be very appreciated. The Result looks like this and, based on the last ID, I just need one row for every og this numbers (all IDs are not strictly consecutive).
A01";261511;2843119;714255;3634457;
A01";261511;2843113;714256;3634457;
A01";261511;2843113;714257;3634457;
A02";261512;2843120;714258;3634464;
A02";261512;2843114;714259;3634464;
....
I think "GROUP BY" may suit your needs.
You can group rows with the same values for a set of columns into a single row
I've been using SQL for about a week at my first full time job, and I'm trying to calculate some statistics from a query where I've combined columns from separate tables.
Specifically, I'm trying to calculate an average from a combined table, where I have applied filters (or constraints? I'm not clear on the SQL lingo).
From doing research on Google, I learned how to calculate an average:
SELECT AVG(column_name)
FROM table_name
The problem I'm having is that this only seems to work with existing tables in the database, not with new queries I have created.
A simplified version of my code is as follows:
SELECT
Animal_Facts.Animal_Name, Animal_Facts.Prev_Reg_Amount,
Names.Given_Name, Animal_Class.Class_Description
FROM
Names
INNER JOIN
Animal_Facts ON Names.Name_Key = Animal_Facts.Name_Key
INNER JOIN
Animal_Class ON Animal_Facts.Class_Key = Animal_Class.Class_Key
This query creates combines four columns from three tables, where Class_Description describes whether the animal is desexed, microchipped, owned by a pensioner etc, and Pre_Reg_Amount is the registration fee paid.
I want to find the average fee paid by pensioners, so I included the following line of code to filter the table:
AND Animal_Class.Class_Description LIKE ('%pensioner%')
And then to calculate the average I add:
SELECT AVG(Animal_Facts.Prev_Reg_Amount) from Animal_Facts
So my total code is:
SELECT
Animal_Facts.Animal_Name, Animal_Facts.Prev_Reg_Amount,
Names.Given_Name, Animal_Class.Class_Description
FROM
Names
INNER JOIN
Animal_Facts ON Names.Name_Key = Animal_Facts.Name_Key
INNER JOIN
Animal_Class ON Animal_Facts.Class_Key = Animal_Class.Class_Key
AND Animal_Class.Class_Description LIKE ('%pensioner%')
SELECT AVG(Animal_Facts.Prev_Reg_Amount)
FROM Animal_Facts
Now the problem is, after checking this calculation in Excel, I'm not actually getting the average of the pensioner data, but the average of all the data. Is there a way to calculate averages (and other statistics) directly from my created table in SQL?
Note: I am able to calculate all these statistics by exporting the data to Excel, but it is much more time consuming. I'd much rather learn how to do this within SQL.
SELECT AVG(af.Prev_Reg_Amount)
FROM
Animal_Facts af
INNER JOIN Animal_Class ac
ON af.Class_Key = ac.Class_Key
AND Class_Description LIKE ('%pensioner%')
I am trying to sum up one field and use it in another query, but when I use the Totals button and then call that sum from the other query it considers that field as multiple instances but with the sum value in each one. How can I sum two fields in two different queries and then use those sums in another query? Note - I only separated them into 3 queries because I felt it would help me avoid "is not part of an aggregate function" errors.
Example Data
Inventory Query: This query groups by item and sums the qty_on_hand field
Item SumOfqty_on_hand
A 300
Job Material query: This query groups on the job's materials and sums up the qty_req field (quantity required to complete the job)
Item SumOfqty_req
A 500
When I make a third query to do the calculation [SumOfqty_req]-[SumOfqty_on_hand] the query does the calculation but for each record in the Job Material query.
Job Material Query
SELECT dbo_jobmatl.item,
IIf(([qty_released]-[qty_complete])<0,0,([qty_released]-[qty_complete]))*[matl_qty] AS qty_req
FROM new_BENInventory
INNER JOIN (dbo_jobmatl
INNER JOIN new_BENJobs
ON (new_BENJobs.suffix = dbo_jobmatl.suffix)
AND (dbo_jobmatl.job = new_BENJobs.job)
) ON new_BENInventory.item = dbo_jobmatl.item
GROUP BY dbo_jobmatl.item,
IIf(([qty_released]-[qty_complete])<0,0,([qty_released]-[qty_complete]))*[matl_qty];
Inventory Query
SELECT dbo_ISW_LPItem.item,
Sum(dbo_ISW_LPItem.qty_on_hand) AS SumOfqty_on_hand,
dbo_ISW_LP.whse,
dbo_ISW_LPItem.hold_flag
FROM (dbo_ISW_LP INNER JOIN dbo_ISW_LPItem
ON dbo_ISW_LP.lp_num = dbo_ISW_LPItem.lp_num)
INNER JOIN dbo_ISW_LPLot
ON (dbo_ISW_LPItem.lp_num = dbo_ISW_LPLot.lp_num)
AND (dbo_ISW_LPItem.item = dbo_ISW_LPLot.item)
AND (dbo_ISW_LPItem.qty_on_hand = dbo_ISW_LPLot.qty_on_hand)
GROUP BY dbo_ISW_LPItem.item,
dbo_ISW_LP.whse,
dbo_ISW_LPItem.hold_flag
HAVING (((Sum(dbo_ISW_LPItem.qty_on_hand))>0)
AND ((dbo_ISW_LP.whse) Like "BEN")
AND ((dbo_ISW_LPItem.hold_flag) Like 0));
Third Query
SELECT new_BENJobItems.item,
[qty_req]-[SumOfqty_on_hand] AS [Transfer QTY]
FROM new_BENInventory
INNER JOIN new_BENJobItems
ON new_BENInventory.item = new_BENJobItems.item;
Please note that anything that starts with dbo_ is a prefix for a table that sources the original data.
If any more clarification is needed I would be more than happy to provide it.
Looks like you need a GROUP BY new_BENJobItems.item on your final query along with a SUM() on the quantity. Or to remove the IIf(([qty_released]-[qty_complete])<0,0,([qty_released]-[qty_complete]))*[matl_qty] from your Job Material query. Or both. As written, the Job Material Query is going to return a record for every different key value in the joined input tables that has a distinct quantity, which doesn't seem like the granularity you want for that.
Im writing a query that sums order values broken down by product groups - problem is that when I add joins the aggregated SUM gets greatly inflated - I assume its because its adding in duplicate rows. Im kinda new to SQL, but I think its because I need to construct the query with sub selects or nested joins?
All data returns as expected, and my joins pull out the needed data, but the SUM(inv.item_total) AS Value returned is much higher that it should be - SQL below
SELECT so.Company_id, SUM(inv.item_total) AS Value, co.company_name,
agents.short_desc, stock_type.short_desc AS Type
FROM SORDER as so
JOIN company AS co ON co.company_id = so.company_id
JOIN invoice AS inv ON inv.Sorder_id = so.Sorder_id
JOIN sorder_item AS soitem ON soitem.sorder_id = so.Sorder_id
JOIN STOCK AS stock ON stock.stock_id = soitem.stock_id
JOIN stock_type AS stock_type ON stock_type.stype_id = stock.stype_id
JOIN AGENTS AS AGENTS ON agents.agent_id = co.agent_id
WHERE
co.last_ordered >'01-JAN-2012' and so.Sotype_id='1'
GROUP BY so.Company_id,co.company_name,agents.short_desc, stock_type.short_desc
Any guidence on how I should structure this query to pull out an "un-duplicated" SUM(inv.item_total) AS Value much appreciated.
To get an accurate sum, you want only the joins that are needed. So, this version should work:
SELECT so.Company_id, SUM(inv.item_total) AS Value, co.company_name
FROM SORDER so JOIN
company co
ON co.company_id = so.company_id JOIN
invoice inv
ON inv.Sorder_id = so.Sorder_id
group by so.Company_id, co.company_name
You can then add in one join at a time to see where the multiplication is taking place. I'm guessing it has to do with the agents.
It sounds like the joins are not accurate.
First suspect join
For example, would an agent be per company, or per invoice?
If it is per order, then should the join be something along the lines of
JOIN AGENTS AS AGENTS ON agents.agent_id = inv.agent_id
Second suspect join
Can one order have many items, and many invoices at the same time? That can cause problems as well. Say an order has 3 items and 3 invoices were sent out. According to your joins, the same item will show up 3 times means a total of 9 line items where there should be only 3. You may need to eliminate the invoices table
Possible way to solve this on your own:
I would remove all the grouping and sums, and see if you can filter by one invoice produce an unique set of rows for all the data.
Start with an invoice that has just one item and inspect your result set for accuracy. If that works, then add another invoice that has multiple and check the rows to see if you get your perfect dataset back. If not, then the columns that have repeating values (Company Name, Item Name, Agent Name, etc) are usually a good starting point for checking up on why the duplicates are showing up.
This is all going to have to be pseudo as I am on my phone and have no internet access right now as I have just moved but its bugging the crap out of me. This also means I can't do code blocks please bear with me: I'll try.
I have a table with amounts in it, and I have a table with labels. I want to sum the amounts in the first table grouped by the labels. The problem is, if there are no records for a label existing in the table with the amounts then I don't get a record in the result set for that label. I need a record there with nulls for the amount tables field. Here is what some sample data might look like:
Amount_table:
Columns: id, tpa, amt, link_to_label_table
Data:
1, GTL, 2000, 1
2, GTL, 1000, 1
Label_table:
Columns: link_to_amount_table, label_name
Data:
1, Label1
2, Label2
Query:
Select at.tpa, sum(at.amt) as amt, lt.label_name
From Amount_table as at
Left join Label_tabl lt on lt.link_to_amount_table = at.link_to_label_table
Where at.tpa = 'GTL'
Group by lt.label, at.tpa
Now this returns:
GTL, 3000, Label1
I tried selecting from the labels table then left joining the amount table and it still didn't give my desired results which are:
GTL, 3000, Label1
Null, Null, Label2
Is this possible with the sum and group by? The fields being grouped by have to be there otherwise you get an error.
This is in DB2 by the way. Is there any way possible to get this to return the way I need it? I have to get the labels; they are dynamic.
On the face of it, you want to have your labels table as the dominant table and the amounts table as the one that is outer joined.
SELECT a.tpa, sum(a.amt) as amt, l.label_name
FROM Label_table AS l
LEFT JOIN Amount_table AS a
ON l.link_to_amount_table = a.link_to_label_table
GROUP BY l.label, a.tpa
You have a condition Amount_table.tpa = 'GTL'; it is not entirely clear why you have that, but presumably it is significant with more data in the tables. There are (at least) two ways you can incorporate that condition into the query (other than the one you chose - which eliminates the rows where a.tpa is null).
SELECT a.tpa, sum(a.amt) as amt, l.label_name
FROM Label_table AS l
LEFT JOIN Amount_table AS a
ON l.link_to_amount_table = a.link_to_label_table
AND a.tpa = 'GTL'
GROUP BY l.label, a.tpa
Or:
SELECT a.tpa, sum(a.amt) as amt, l.label_name
FROM Label_table AS l
LEFT JOIN (SELECT *
FROM Amount_table
WHERE tpa = 'GTL') AS a
ON l.link_to_amount_table = a.link_to_label_table
GROUP BY l.label, a.tpa
A decent optimizer will produce the same query plan for both, so it probably doesn't matter which you use. There's an argument that suggests the second alternative is cleaner in that the ON clause is primarily for joining conditions, and the filter condition on a.tpa is not a joining condition. There's another argument that says the first alternative avoids a sub-query and is therefore preferable. I'd validate that the query plans are the same and would probably choose the second, but it is a somewhat nebulous decision based on a mild preference.
You were so close on your second try. Change WHERE to AND. This has the effect of applying at.tpa='GTL' to the JOIN instead of applying it to the filter so you don't filter out the NULLs.