All,
I have 2 tables in Access. Let's call them RepQ1 and Des. There are 2 fields in these 2 tables which I am trying to match and get matching records. These 2 fields are of TEXT data type. Following is the query that I am using.
SELECT * FROM RepQ1 LEFT JOIN Des ON Rep.Mat=Des.MatD;
When I run this, I get no result displayed. Please advise.
Check with this query
SELECT * FROM RepQ1 WHERE RepQ1.Mat IN (SELECT DISTINCT MatD FROM Des);
Related
I am trying to build a query that will generate a list of records based on the results of a very similar query.
Here are the details and examples
Query 1: Generate a list if part #'s in a specific location of the warehouse.
Query 2: Use the list of part #'s generated in #1 to show all locations for the list of part #'s, assuming they will be in both the location specified in #1 and other locations.
Query 1 looks like this:
Select
ItemMaster.ItemNo, BinInfo.BIN, ItemDetail.Qty, ItemDetail.Whouse_ID
From
((ItemDetail
Left Join
ItemMaster on ItemMaster.ID=ItemDetail.Item_ID)
Left Join
BinInfo on BinInfo.ID = ItemDetail.Bin_ID)
Where
ItemDetail.Whouse_ID = '1'
And BinInfo.Bin = 'VLM';
Query 2 needs to be almost identical except the ItemMaster.ItemNo list will come from query #1.
Any help here would be great. I don't know if I need to learn Unions, Nested Queries, or what.
make sure that your first query returns the list of ids that you need.
then write the second query with the WHERE id IN (...) syntax:
SELECT * FROM table1 WHERE id IN
(SELECT id FROM table2 WHERE...) -- first query
I'm using MS SqlServer 2008. And I have a table 'Users'. This table has the key field ID of bigint. And also a field Parents of varchar which encodes all chain of user's parent IDs.
For example:
User table:
ID | Parents
1 | null
2 | ..
3 | ..
4 | 3,2,1
Here user 1 has no parents and user 4 has a chain of parents 3->2->1. I created a function which parses the user's Parents field and returns result table with user IDs of bigint.
Now I need a query which will select and join IDs of some requested users and theirs parents (order of users and theirs parents is not important). I'm not an SQL expert so all I could come up with is the following:
WITH CTE AS(
SELECT
ID,
Parents
FROM
[Users]
WHERE
(
[Users].Name = 'John'
)
UNION ALL
SELECT
[Users].Id,
[Users].Parents
FROM [Users], CTE
WHERE
(
[Users].ID in (SELECT * FROM GetUserParents(CTE.ID, CTE.Parents) )
))
SELECT * FROM CTE
And basically it works. But performance of this query is very poor. I believe WHERE .. IN .. expression here is a bottle neck. As I understand - instead of just joining the first subquery of CTE (ID's of found users) with results of GetUserParents (ID's of user parents) it has to enumerate all users in the Users table and check whether the each of them is a part of the function's result (and judging on execution plan - Sql Server does distinct order of the result to improve performance of WHERE .. IN .. statement - which is logical by itself but in general is not required for my goal. But this distinct order takes 70% of execution time of the query). So I wonder how this query could be improved or perhaps somebody could suggest some another approach to solve this problem at all?
Thanks for any help!
The recursive query in the question looks redundant since you already form the list of IDs needed in GetUserParents. Maybe change this into SELECT from Users and GetUserParents() with WHERE/JOIN.
select Users.*
from Users join
(select ParentId
from (SELECT * FROM Users where Users.Name='John') as U
cross apply [GetDocumentParents](U.ID, U.Family, U.Parents))
as gup
on Users.ID = gup.ParentId
Since GetDocumentParents expects scalars and select... where produces a table, we need to apply the function to each row of the table (even if we "know" there's only one). That's what apply does.
I used indents to emphasize the conceptual parts of the query. (select...) as gup is the entity Users is join'd with; (select...) as U cross apply fn() is the argument to FROM.
The key knowledge to understanding this query is to know how the cross apply works:
it's a part of a FROM clause (quite unexpectedly; so the syntax is at FROM (Transact-SQL))
it transforms the table expression left of it, and the result becomes the argument for the FROM (i emphasized this with indent)
The transformation is: for each row, it
runs a table expression right of it (in this case, a call of a table-valued function), using this row
adds to the result set the columns from the row, followed by the columns from the call. (In our case, the table returned from the function has a single column named ParentId)
So, if the call returns multiple rows, the added records will be the same row from the table appended with each row from the function.
This is a cross apply so rows will only be added if the function returns anything. If this was the other flavor, outer apply, a single row would be added anyway, followed by a NULL in the function's column if it returned nothing.
This "parsing" thing violates even the 1NF. Make Parents field contain only the immediate parent (preferably, a foreign key), then an entire subtree can be retrieved with a recursive query.
I have a very simple database. It contains 3 tables. The first is the primary input table where values go in. The 2nd and 3rd are there purely for translating values to names for a view. When I view the rows in table 1, I can see that column businessUnit contains valid values in all rows. When I add the Business_Units table (The 3rd table in this DB), all but 2 rows go away and despite the businessUnit value both being 1 in the 1st table, the view gives them different names.
I created a DB diagram and uploaded a screenshot to imgur. Link: http://imgur.com/jXF7L1R
I only have 2 relationships in the table. One from equipType on New_Equipment_User to id in Equipment_Type and one from businessUnit in New_Equipment_User to id in Business_Units. The weird thing is that the Equipment Type works perfectly, yet when I replicate the table, relationship and view information exactly, it doesn't work. Instead of 6 rows appearing, there are only 2 which share the same value in businessUnit, but gives 2 different names for it.
In case it matters, here is my view Query:
SELECT dbo.New_Equipment_User.id, dbo.Equipment_Type.name AS equipType, dbo.New_Equipment_User.jobNumber, dbo.New_Equipment_User.costCode,
dbo.New_Equipment_User.reason, dbo.New_Equipment_User.mobile, dbo.New_Equipment_User.mobileQty, dbo.New_Equipment_User.mobileComment,
dbo.New_Equipment_User.laptop, dbo.New_Equipment_User.laptopQty, dbo.New_Equipment_User.laptopComment, dbo.New_Equipment_User.desktop,
dbo.New_Equipment_User.desktopQty, dbo.New_Equipment_User.desktopComment, dbo.New_Equipment_User.modem, dbo.New_Equipment_User.modemQty,
dbo.New_Equipment_User.modemComment, dbo.New_Equipment_User.printer, dbo.New_Equipment_User.printerQty, dbo.New_Equipment_User.printerComment,
dbo.New_Equipment_User.camera, dbo.New_Equipment_User.cameraQty, dbo.New_Equipment_User.cameraComment, dbo.New_Equipment_User.dateRequired,
dbo.New_Equipment_User.requestedBy, dbo.New_Equipment_User.dateRequested, dbo.New_Equipment_User.approvalStatus,
dbo.Business_Units.name AS businessUnit
FROM dbo.New_Equipment_User
JOIN dbo.Equipment_Type ON dbo.New_Equipment_User.equipType = dbo.Equipment_Type.id
JOIN dbo.Business_Units ON dbo.New_Equipment_User.id = dbo.Business_Units.id
WHERE (dbo.New_Equipment_User.approvalStatus = '0')
And here is an image of the view since it is easier to read: http://imgur.com/pZ97ehQ
Is anyone able to assist with why this might be happening?
Try using a LEFT JOIN
SELECT ...
FROM dbo.New_Equipment_User
JOIN dbo.Equipment_Type ON dbo.New_Equipment_User.equipType = dbo.Equipment_Type.id
LEFT JOIN dbo.Business_Units ON dbo.New_Equipment_User.id = dbo.Business_Units.id
This will ensure that all dbo.New_Equipment_User and all dbo.Equipment_Type is present
I have a SQL Server 2008 database that has two tables. These two tables are CoreGroup and CoreGroupMember. Please note, I did not setup these tables. Regardless, the table structure is:
CoreGroup
---------
ID
GroupMember1MemberName
GroupMember2MemberName
GroupMember3MemberName
GroupMember4MemberName
CoreGroupMember
---------------
ID
CoreGroupID
MemberName
I need to determine how many CoreGroup records are associated with a CoreGroupMember with a specific MemberName. There is one catch that is really throwing me for a loop though. Some CoreGroup records only have one member associated with them. I need to retrieve the CoreGroup records that have multiple CoreGroupMember records where at least one of the records has the specific MemberName. I can't seem to figure out the multiple record part. Can someone please help me?
Thank you!
I'll take a stab at it hoping I've understood the requirements correctly. First, I use a cte to find all groups with multiple members, then use that result set to find groups with your specific member.
with cteMultipleMembers as (
select cg.ID, COUNT(*) as MemberCount
from CoreGroup cg
inner join CoreGroupMember cgm
on cg.ID = cgm.CoreGroupID
group by cg.ID
having COUNT(*) > 1
)
select mm.ID
from cteMultipleMembers mm
inner join CoreGroupMember cgm
on mm.ID = cgm.CoreGroupID
and cgm.MemberName = #YourMemberName
Don't ask for what, but i need two tables from one SQL query.
Like this...
Select Abc, Dgf from A
and result are two tables
abc
1
1
1
dgf
2
2
2
More details?
Ok lets try.
Now i have sp like this:
SELECT a.* from ActivityView as a with (nolock)
where a.WorkplaceGuid = #WorkplaceGuid
SELECT b.* from ActivityView as a with (nolock)
left join PersonView as b with (nolock) on a.PersonGuid=b.PersonGuid where a.WorkplaceGuid = #WorkplaceGuid
It's cool. But execution time about 22 seconds. I do this because in my programm i have classes that automaticly get data from records set. Class Activity and class Person. That why i can't make it in one recordset. Program didn't parse it.
You can write a stored procedure that has two SELECTs.
SELECT Abc FROM A AS AbcTable;
SELECT Dgf FROM A AS DfgTable;
Depending on your specific requirements, I would consider just submitting two separate queries. I don't see any advantage to combining them.
SQL Server supports legacy COMPUTE BY clause which acts almost like GROUP BY but returns multiple resultsets (the resultsets constituting each group followed by the resultsets with the aggregates):
WITH q AS
(
SELECT 1 AS id
UNION ALL
SELECT 2 AS id
)
SELECT *
FROM q
ORDER BY
id
COMPUTE COUNT(id)
BY id
This, however, is obsolete and is to be removed in the future releases.
Those don't seem to be excessively complicated queries (although select * should in general not be used in production and never when you are doing a join as it needlessly wastes resources sending the value of the joined field twice). Therefore if it is taking 22 seconds, then either you are returning a huge amount of data or you don't have proper indexing.
Have you looked at the execution plans to see what is causing the slowness?