Select Command - Left Join Versus Inner Join
Aug 9, 2013Why would I use a left join instead of a inner join when the columns entered within the SELECT command determine what is displayed from the query results?
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Left Outer Join Versus Subquery
Sep 13, 2006Hello Chaps,
I have got question about the performance of subquery and left outer join
My scenario is that I have two tables Customer Mater and address book.
Customer Mater and address book tables hold the record for both carrier and customer. and i want retrieve the record for customer and related carrier as well
i have two options
1. either use left outer join (i.e. Join Customer master to Address Book 2 times, 1 for customer and 1 for carrier) by:
Address book (as customer) Left outer Join Customer Master (on related Key)
AddressBook (as carrier) Left Outer Join Customer master (on related Key)
2.or use 1 join for customer and use subquery to retrieve carrier name (from Customer table) as I only need that one
Address Book AB (as Customer) Join Customer Master CM
Subquery: Select carrier_name From customer_master cm2 where cm2.carrier = ab.carrier
can any one tell one which is the best as far as performance is concern. My opinion is that the subquery is better becuase left outer join will have the overhread of extra columns... not pretty sure about it..
Any idea?
regards,
Anas
Left Join Vs Left Outer Join Syntax Generates Different Execution Plans
Apr 16, 2008
Anyone know why using
SELECT *
FROM a LEFT OUTER JOIN b
ON a.id = b.id
instead of
SELECT *
FROM a LEFT JOIN b
ON a.id = b.id
generates a different execution plan?
My query is more complex, but when I change "LEFT OUTER JOIN" to "LEFT JOIN" I get a different execution plan, which is absolutely baffling me! Especially considering everything I know and was able to research essentially said the "OUTER" is implied in "LEFT JOIN".
Any enlightenment is very appreciated.
Thanks
VBScript, SQL And The LEFT OUTER JOIN Command
Sep 12, 2007Hello,
I have only started VBS and SQL a week ago so..
The scenario is that I have 1 SQL db and 3 tables as follows:
tblSAVDetails (columns SERVERS : SAVGroup : SAVParent)
tblSAVComputers (Columns SERVERS)
tblSAVResults (Columns SERVERS : SAVGroup : SAVParent)
The tblSAVDetails has raw data from all of our servers nationwide
The tblSAVComputers have a list of servers in our site
The SAVResults will store the results of the query
I want compare the list of servers in tblSAVComputers with the list contained in tblSAVDetails and IF it finds the server to then retrieve the details. However if it doesn't find the server I want to flag it (with a NULL or NA or somthing). After all that I want it to insert the results into tblSAVResults.
The SQL command I am using is:
---------
SELECT *
FROM tblSAVComputers LEFT OUTER JOIN
tblSAVDetails ON tblSAVComputers.SAVComputers = tblSAVDetails.SERVERS
---------
I have tried so many ways, but I just cant get it to work. I know how to insert data into a DB, but I just cant get this command to work in vbScript (it works fine if I run it directly on the SQL server)
Any help would be brilliant! If you need more info, please let me know.
Thanks
Integration Services :: How To Perform Left Restricted Join In Merge Join Transformation
May 22, 2015I have two xml source and i need only left restricted data.
how can i perform left restricted join?
Transact SQL :: Difference Between Inner Join And Left Outer Join In Multi-table Joins?
Oct 8, 2015I was writing a query using both left outer join and inner join. And the query was ....
SELECT
S.companyname AS supplier, S.country,P.productid, P.productname, P.unitprice,C.categoryname
FROM
Production.Suppliers AS S LEFT OUTER JOIN
(Production.Products AS P
INNER JOIN Production.Categories AS C
[code]....
However ,the result that i got was correct.But when i did the same query using the left outer join in both the cases
i.e..
SELECT
S.companyname AS supplier, S.country,P.productid, P.productname, P.unitprice,C.categoryname
FROM
Production.Suppliers AS S LEFT OUTER JOIN
(Production.Products AS P
LEFT OUTER JOIN Production.Categories AS C
ON C.categoryid = P.categoryid)
ON
S.supplierid = P.supplierid
WHERE
S.country = N'Japan';
The result i got was same,i.e
supplier country productid productname unitprice categorynameSupplier QOVFD Japan 9 Product AOZBW 97.00 Meat/PoultrySupplier QOVFD Japan 10 Product YHXGE 31.00 SeafoodSupplier QOVFD Japan 74 Product BKAZJ 10.00 ProduceSupplier QWUSF Japan 13 Product POXFU 6.00 SeafoodSupplier QWUSF Japan 14 Product PWCJB 23.25 ProduceSupplier QWUSF Japan 15 Product KSZOI 15.50 CondimentsSupplier XYZ Japan NULL NULL NULL NULLSupplier XYZ Japan NULL NULL NULL NULL
and this time also i got the same result.My question is that is there any specific reason to use inner join when join the third table and not the left outer join.
Select DISTINCT In LEFT JOIN
Feb 14, 2008Hi again,
I have this SQL (part of a stored procedure) where I do LEFT JOIN. SELECT callingPartyNumber, AlertingName, originalCalledPartyNumber, finalCalledPartyNumber,
dateTimeConnect,
dateTimeDisconnect,
CONVERT(char(8), DATEADD(second, duration, '0:00:00'), 108) AS duration,
clientMatterCode
FROM CDR1.dbo.CallDetailRecord t1
LEFT JOIN CDR2.dbo.NumPlan t2 ON t1.callingPartyNumber=t2.DNorPattern
WHERE
(t1.callingPartyNumber LIKE ISNULL(@callingPartyNumber, t1.callingPartyNumber) + '%') AND
(t1.originalCalledPartyNumber LIKE ISNULL(@originalCalledPartyNumber, t1.originalCalledPartyNumber) + '%') AND
(t1.finalCalledPartyNumber LIKE ISNULL(@finalCalledPartyNumber, t1.finalCalledPartyNumber) + '%') AND
(t1.clientMatterCode LIKE ISNULL(@clientMatterCode, t1.clientMatterCode) + '%') AND
(@callerName is NULL OR t2.AlertingName LIKE '%' + @callerName + '%') AND
(t1.duration >= @theDuration) AND
((t1.datetimeConnect) >= ISNULL(convert(bigint,
datediff(ss, '01-01-1970 00:00:00', @dateTimeConnect)), t1.datetimeConnect)) AND
((t1.dateTimeDisconnect) <= ISNULL(convert(bigint,
datediff(ss, '01-01-1970 00:00:00', @dateTimeDisconnect)), t1.dateTimeDisconnect))
The problem is that if the t2 has more than one entry for the same DNorPattern, it pulls the record more than once. So say t1 has a callingPartyNumber = 1000. t2 has two records for this number. It will pull it more than once. How do I get the Unique value.
What I am trying to get is the AlertingName (name of the caller) field value from t2 based on DNorPattern (which is the phone number).
If this is not clear, please let me know.
Thanks,
Bullpit
Double SELECT To (LEFT) JOIN
Jul 26, 2013I am currently working with 2 tables:
tbl_users: UserID,Username,ClientFK
tbl_clients: ClientID, ClientName
Now I want to get all Users with same Client but my parameter of my stored procedure is @Username.
This code works fine:
SELECT
UserID,
ClientFK,
WebLogin,
WebPassword,
WindowsUsername,
BasePriority,
IsAdmin,
DateCreated,
Enabled
FROM tbl_User
WHERE ClientFK = (SELECT [ClientFK] FROM tbl_User WHERE [WindowsUsername] = 'Livermorium')
But i don't want to have 2 selects and prefer a left join.
Is it possible to write a better select statement?
Sub-select Vs. LEFT OUTER JOIN
May 11, 2007I think it is quite often when you need to view some records, which refer (by key) to data in other tables. For instance, a user belongs to a group but it is preferable to show group name in the user data rather than group id. The options are
1) LEFT OUTER JOIN:
SELECT users.id, groups.name FROM users LEFT OUTER JOIN groups ON users.[group] = groups.id
2) A Subselect:
SELECT id, [group] = (SELECT [name] FROM groups WHERE id = users.[group]) FROM users
Which is better and why?
'Left Outer Merge Join' Failing To Join Valid Row
Aug 10, 2007Scenario:
OLEDB source 1
SELECT ...
,[MANUAL DCD ID] <-- this column set to sort order = 1
...
FROM [dbo].[XLSDCI] ORDER BY [MANUAL DCD ID] ASC
OLEDB source 2
SELECT ...
,[Bo Tkt Num] <-- this column set to sort order = 1
...
FROM ....[dbo].[FFFenics] ORDER BY [Bo Tkt Num] ASC
These two tasks are followed immediately by a MERGE JOIN
All columns in source1 are ticked, all column in source2 are ticked, join key is shown above.
join type is left outer join (source 1 -> source 2)
result of source1 (..dcd column)
...
4-400-8000119
4-400-8000120
4-400-8000121
4-400-8000122 <--row not joining
4-400-8000123
4-400-8000124
...
result of source2 (..tkt num column)
...
4-400-1000118
4-400-1000119
4-400-1000120
4-400-1000121
4-400-1000122 <--row not joining
4-400-1000123
4-400-1000124
4-400-1000125
...
All other rows are joining as expected.
Why is it failing for this one row?
Transact SQL :: Select From A Select Using Row Number With Left Join
Aug 20, 2015The select command below will output one patient’s information in 1 row:
Patient id
Last name
First name
Address 1
OP Coverage Plan 1
OP Policy # 1
OP Coverage Plan 2
[code]...
This works great if there is at least one OP coverage. There are 3 tables in which to get information which are the patient table, the coverage table, and the coverage history table. The coverage table links to the patient table via pat_id and it tells me the patient's coverage plan and in which priority to bill. The coverage history table links to the patient and coverage table via patient id and coverage plan and it gives me the effective date.
select src.pat_id, lname, fname, addr1,
max(case when rn = 1 then src.coverage_plan_ end) as OP_Coverage1,
max(case when rn = 1 then src.policy_id end) as OP_Policy1,
code]...
Transact SQL :: How To Select A Single Record In A Left Join
Sep 16, 2015My tables look like this:
Users //
table
UserID // pk
UserName // varchar
UserFamilyName // varchar
User_Friends //
table
FriendsID // pk
UserID // fk
FamilyName // varchar
MY query:
SELECT
U.UserFamilyName, F.FamilyName
FROM
Users U LEFT
JOIN User_Friends
F ON U.UserID =
F.UserID
WHERE
U.UserName = ‘JOHN’
How do I adjust my query to select just the very first record from Users_friends, I want only the top first one.And if there are no friends how can I return an empty string instead of Null.
Right Join Returns Same Results As Left Join
Feb 5, 2015Why does this right join return the same results as using a left (or even a full join)?There are 470 records in Account, and there are 1611 records in Contact. But any join returns 793 records.
select Contact.firstname, Contact.lastname, Account.[Account Name]
from Contact
right join Account
on Contact.[Account Name] = Account.[Account Name]
where Contact.[Account Name] = Account.[Account Name]
How To Join 3 Tables Using Left Or Right Join Keyword?
Aug 17, 2007Hi guys,
I'll appreciate any help with the following problem:
I need to retrieve data from 3 tables. 2 master tables and 1 transaction table.
1. Master table TBLOC contain 2 records :
rcd 1. S01
rcd 2. S02
2. Master table TBCODE contain 5 records:
rcd 1. C1
rcd 2. C2
rcd 3. C3
rcd 4. C4
rcd 5. C5
3. Transaction table TBITEM contain 4 records which link to 2 master table:
rcd 1. S01, C1, CAR
rcd 2. S01, C4, TOY
rcd 3. S01, C5, KEY
rcd 4. S02, C2, CAR
I use Left Join & Right Join to retrieve result below (using non-ASNI method) but it doesn't work.
Right Join method:
SELECT C.LOC, B.CODE, A.ITEM FROM TBITEM A RIGHT JOIN TBCODE B ON A.CODE = B.CODE
RIGHT JOIN TBLOC C ON A.LOC = C.LOC
GROUP BY C.LOC, B.CODE, A.ITEM ORDER BY C.LOC, B.CODE
When I use Non-ASNI method it work:
SELECT C.LOC, B.CODE, A.ITEM FROM TBITEM A, TBCODE B, TBLOC C
WHERE A.CODE =* B.CODE AND A.LOC =* C.LOC
GROUP BY C.LOC, B.CODE, A.ITEM ORDER BY C.LOC, B.CODE
Result:
LOC CODE ITEM
-----------------------------
S01 C1 NULL
S01 C2 NULL
S01 C3 CAR
S01 C4 TOY
S01 C5 KEY
S02 C1 NULL
S02 C2 CAR
S02 C3 NULL
S02 C4 NULL
S02 C5 NULL
Please Help.
Thanks.
Left Join Vs Left Outer Join
Apr 7, 2008Is there any difference between left join and left outer join in sql server 2000?please reply with example if any?
Thanks in advance
Left Join Vs Left Outer Join
May 14, 2008Hi,
Whats the diference between a left join and a left outer Join
How To Join Two Tables By Select Command?
Apr 11, 2008Hi
I have a tables like below
TblA
ID(unique)---SessionID(unique)----Ref
TblB
VisitID(unique)---SessionID(Multiple)----Page--Pdcode
My question : How Do I bring all rows from TblB and matching single row from TblA (I have more than one sessionID in TblB and only one Unique SessionID in TblA).
The Select query I was using is
SELECT PageViews.ID AS ID, PageDetailView.VisitID, PageViews.PageAccessed, PageDetailView.PageAccessed AS Expr1, PageViews.QueryString,
PageDetailView.QueryString AS Expr2, PageViews.Referer, PageViews.SessionID, PageDetailView.SessionID AS Expr3, PageDetailView.PdtID,
PageDetailView.Pcode, PageDetailView.CustID, PageDetailView.OrdTot, PageViews.[Date]
FROM PageViews RIGHT OUTER JOIN
PageDetailView ON PageViews.SessionID = PageDetailView.SessionID
ORDER BY PageViews.ID DESC
Getting Count(*) From Left Side Of Join Using WHERE On Right Side Of Join
Jul 3, 2006Hi,I have 2 tables: tblStatements and tblLines (one to many) AnytblStatements record can have many associated records in tblLines.The search criteria is against tblLines (ie tblLines.fldDateofService
Quote:
Can Any One Tell Me The Difference Between Cross Join, Inner Join And Outer Join In Laymans Language
Apr 30, 2008Hello
Can any one tell me the difference between Cross Join, inner join and outer join in laymans language
by just taking examples of two tables such as Customers and Customer Addresses
Thank You
SQL LEFT JOIN Help
Jan 26, 2007I'm trying to join 2 tables. I thought I was getting the correct results but it turns out I'm not.
My Query:
SELECT IVINVA, IVORDN, IVCSLN, IVRESR, IVCITM, CONVERT(varchar(12),CAST(IVIAMT as money),1) AS ExtPrice, CONVERT(varchar(12),CAST(IVPIVC as money),1) AS DistPrice, IVCSUM, IVQYCS, IVDESC, OIRESR, OIDPCT, CONVERT(varchar(12),CAST(IVPIVC - (OIDPCT / 100 * IVPIVC) as money),1) AS NetPrice FROM INVDET1_TBL LEFT JOIN ORDDIS_TBL ON ORDDIS_TBL.OIORDN = INVDET1_TBL.IVORDN AND ORDDIS_TBL.OIRESR = INVDET1_TBL.IVRESR WHERE IVORDN = '0859919' AND IVINVA = '00324024'
Basically, my problem lies in the seonc condition of the LEFT JOIN. I needed to set the two tables equal my item number, because in some situations I need that logic to get the correct result. It most other cases, that item column in the ORDDIS_TBL is NULL, thus giving me the wrong results. In that case, I would want the JOIN to only be ORDDIS_TBL.OIORDN = INVDET1_TBL.IVORDN, and not include the second part. Is there a way I can condition this with an If statement, If ORDDIS_TBL.OIRESR is Null then do this join, if not, then do this? I'm confused how to get the proper result here.
Left Join Help
Jul 7, 2005I need to make a left join from the freezefile f, to sped s, instead of having f.studentid = s.id in the where clause. Any help??
select f.studentid, f.studentname, f.sex, fs.mealstatus, s.except, s.lre, r.description, g.testid, g.scale_la, g.scale_ma, t.test_name, t.year
from freezefile f, fsapps fs, sped s, regtb_exception r, gqe_scores g, test_info t
where
f.type = 'ADM'
and
s.except = r.code
and
t.test_name = 'ISTEP'
and
t.year = 2004
and
g.testid = t.testid
and
f.studentid = fs.id
and
f.studentid = s.id
and
f.studentid = g.studentid
Left/right Join
Aug 2, 2004i'm shure it's some smal stiupid mistake bat I can't find it, PLZ help.
1)
select komorka from #plantemp
--result
komorka
09
10
I-P
II-P
III-P
SI/1
SI/2
SI/3
2)
select komorka,ustalenia from analiza_1 a where a.koniec between '20040701'and '20040731'
komorka ustalenia
SI/1788138.9300
SI/246638.4900
SI/216218.4000
08.0000
3)
select p.komorka,isnull(sum(ustalenia),0)
from #plantemp p left join analiza_1 a on p.komorka=a.komorka
where a.koniec between '20040701'and '20040731'
group by p.komorka
komorka ustalenia (sum)
08.0000
SI/1788138.9300
SI/262856.8900
I need all rows from table 1 bat right and left join gives me the same results, WHY
Left Join
Jan 9, 2007There are two tables:
tblIndices:
IndexID, Name
1index1
2index2
3index3
.
.
.
tblBasketConstituents
ID, ParentIndexID, ChildIndexID, Weight
121 20
223 80
313 50
412 50
As you can see the ParentIndexID and ChildIndexID fields refer to tblIndices.IndexID
I would like a stored procedure as follows:
show all index names and show the wights for the indexID you passed.
This is what I have so far and it is not correct yet. Not sure what the syntax should be.
alter PROCEDURE [dbo].[uspBasketIndices_Get]
@IndexIDint
AS
select
i.IndexID,
i.[Name],
bc.Weight
from
tblIndices as i left join tblBasketConstituents as bc on i.IndexID = bc.ParentIndexID
and i.IndexID = @IndexID
order by
i.[Name]
How Many 'LEFT JOIN' Is Too Many?
Feb 26, 2004Any one know any facts and figures about maximum Left Joins allowed (or recommended) in one query?
I am running a MS SQL 2000 my database is full of relational data and most of my foreign keys (INT data type) are a Clustered Indexed, Usually I will only be pulling one record from collection of about a dozen tables, but the Database is expected to grow fast and become big.
Right now I have a Stored Proc that has eight(8) LEFT JOINs in it. My worry is that this query will kill me as the database approaches 50,000 records.
Lito
Left Join
Mar 6, 2007Hi all. My query works fine, it generates reports but not my expected result.
select d.fullname, p.nickname, p.birthdate, p.birthplace,
p.gender, p.civilstatus, p.religion, p.nationality, p. weight, p.height,
p.haircolor, p.eyecolor, p.complexion, p.bodybuilt, p.picture, p.dialectspoken,
d.mobilephone, d.prprovince,[Age] = dbo.F_AGE_IN_YEARS( birthdate, getdate() ),
c.name, c.address, c.telno, c.email, c.occupation, ed.year1, ed.year2, ed.degree, sch.schname
from hremployees as e
inner join psdatacenter as d on e.empdcno = d.dcno
inner join pspersonaldata as p on e.empdcno = p.dcno
left join hrappempcharrefs as c on e.empdcno = c.empdcno
left join hrappempeducs as ed on e.empdcno = ed.empdcno
left join hrsetschools as sch on ed.schoolcode = sch.schcode
the above query gives a 77 records
if i ran "select * from hremployees" generates 60 records
i think the error is in the left joining.
hrappempcharrefs, hrappempeducs and hrsetschools must be left joined to hremployees.
thanks
-Ron-
Left Join Using Vb 9.0 And LINQ
Dec 2, 2007Hi Guys,
I started working with linq and vb9.0 but i have a small problem i could feagure how to solve in c# but not in vb
I wanted to make left join or right join on vb 9.0 and linq is it possible or this is only c# feature ?
Waiting to hear from u guys,
Thanks
Softy
Left Outer Join-please Help!
Jan 7, 2002Hello!
I need to write a query using left outer join and I'm having trouble with it.
I have 2 tables:customer and cust_info.
I want to pull all records from customer table and cust_info table even if there is no related data in cust_info table.
But I need one condition in this query:only records from customer table where cus_type in ("A","B","C").
I don't need all other types ("D","E").
So my query looks like this:
select customer.cus_name,customer.cus_address,customer.cu s_type,cus_info.status
from customer
left outer join cus_info ON customer.sxdat_pk = cus_info.sxdat_pk
and cus_type in ("A","B","C")
AND cus_info.cus_table = 'CUSTOMER'
The result should be like this:
cus_name cus_address cus_type status
Amoco 457 bent A new
Bingo 47 lone oak C NULL
Sears 1020 Magic dr. B exist
But my query pulls records for customers with type "D" and "E" that I'm trying to exclude from result.
Please help.
Thanks,
lena
LEFT JOIN Problem
Apr 18, 2008Hello everybody!!!
I have to left join 2 tables. The first consists of columns:id, description, descr_num.
The second table: id, descr_num, value.
I need to extract description from table1 where descr_num is in the range , say, 1-10.
LEFT JOIN
extract value from table2 ,descr_num should be in the same range. in table2 some values from (1,10) and desc_num could be not present.
BUT i want this left join to be limited as i said.
Is there any solution to this prob. without creating temp tables. Or actually can i do such a join?
Thank you
Left Join Table
Jul 18, 2006Now I have a table with the table design as following :
table cst_EmpProfile
intEmpId nvcEmpName nvcEmpAddress intEmployeeType bitActiv
1 Peter Null Null true
2 Juli 1, xxxx 2 true
3 Sam Null Null False
table cst_EmpType
intEmpType nvcEmployeeType
1 Free Enginner
2 Manager
3 Operator
To join the table but MUST follow the condition as bitActiv = TRUE:
select emp.nvcEmpName, emp.nvcEmpAddress, ety. nvcEmployeeType from cst_EmpProfile emp left join cst_EmpType on emp.intEmployeeTypee = ety.intEmpType and emp.bitActiv = 1.
But, the sql statement doesnt output the my expected result.
Because the data row return must be 1st and 2nd row as it bitActiv = true.
So, how's I going achieve what i want. tq.
Stumped - LEFT JOIN
Jan 10, 2007Hi, I'm getting the error Syntax error (missing operator) in query expression 'dbPWork.id = dbPWorkWord.work_id LEFT JOIN words ON dbPWorkWord.word_id = words.id'." on the query below. Everything looks in place to me. Do you see anything that shouldn't work?
Query:
Code:
Code:
SELECT DISTINCT dbPWork.id, description_e as description, w_id , dateStart, dateEnd FROM dbPWork
LEFT JOIN dbPWorkW ON dbWork.id = dbPWorkW.work_id
LEFT JOIN words ON dbPWorkW.word_id = words.id
Everything works fine until I add the second LEFT JOIN statement. Any ideas? I'm stumped.
Left Join Question
Sep 22, 2005I have a left join that doesn't suit my request.
select * from A
left join B
on A.x=B.x
The problem is that for a specific record in A we can find 1 or more entries in B. What I want is to return only the 1st entry found on B.
thx
Difference Between LEFT N RIGHT JOIN
Dec 6, 2005Hi,
I have got a query for you guys. Can any one temme the difference between
"FROM Table_A LEFT JOIN Table_B" and "FROM Table_B RIGHT JOIN Table_A"
;)
Thanks,
Rahul Jha
Left Join And Subquery
May 1, 2004Hi,
Iwant to make a left join between two tables connected with a specific field
but I also want to have some criteria on the right table.
I want to display all the rows from the first(left) table and only the rows from the secod (right) table that match the join and the criteria.
However If I have criteria on the second table the join behaves like an inner join displaying only the rows that exist in both tables.
In MS Access instead of the right table I use a query in which I enter the criteria and then I connect it with a left join in a new query in order to get the right results. How can I do itin MSSQLServer without using Views?
Must I use a subquery with Exists and what is the right syntax in order to achieve this?
Best Regards,
manolis Perrakis