Joining multiple tables in Oracle DB
I have the following tables.
1. AddProject
- projID
- projName
2. AddLab
- labID
- labName
3. ProjLabAssociation
- projID
- labID
4. AddResearchArea
- raID
- raName
5. ProjRAAssociation
- projID
- raID
AddProject is associated with both the tables-AddLab and AddResearchArea
ProjLabAssociation and ProjRAAssociation are association tables which contain the primary keys from corresponding tables. Both the fields in these 2 tables are primary keys.
If AddProject has 3 entries - (Proj1,ProjectA),(Proj2,ProjectB),(Proj3,ProjectC)
AddLab has 2 entries - (Lab1,Bangalore),(Lab2,Chennai)
AddResearchArea has 2 entries - (RA1,Green Computing),(RA2,Cloud Computing)
ProjLabAssociation has 2 entries - (Proj2,Lab1),(Proj3,Lab1)
ProjRAAssociation has 3 entries - (Proj2,RA1),(Proj3,RA1),(Proj3,RA2)
If I am querying by AddLab data for (Lab1,Bangalore), I should be getting the following columns in the result table
Table2ID | Table2Name | Table3ID | Table3Name | Table1ID | Table1Name
Lab1 | Bangalore | RA1 | Green Computing | Proj2 | ProjectB
Lab1 | Bangalore | RA1 | Green Computing | Proj3 | ProjectC
Lab1 | Bangalore | RA2 | Cloud Computing | Proj3 | ProjectC
I have been trying the following commands but I m getting the expected result
1.SELECT * FROM AddLab al, ProjLabAssociation pl, AddProject ap WHERE al.labID = pl.labID(+) and ap.projID = pl.projID(+);An SQLException is thrown saying - java.sql.SQLException: ORA-01417: a table may be outer joined to at most one other table
2.SELECT * FROM AddLab,AddProject,AddResearchArea WHERE labID in
(select al.labID from ProjLabAssociation pl,AddLab al where al.labID = pl.labID)
AND projID in
(select ap.projID from ProjLabAssociation pl,Addproject ap where ap.projID = pl.projID)
AND themeID in
(select ar.raID from ProjRAAssociation pr, AddResearchArea ar where ar.raID = pr.raID)
AND projID in
(select ap.projID from ProjRAAssociation pr,Addproject ap where ap.projID = pr.projID)
ORDER BY labID;I am not getting the expcted results here
Oracle version : 9i 10g/11g
Can anyone help me in this.
Edited by: user9205634 on Dec 22, 2011 3:40 AM
1. Always tell the community your Oracle version
2. If you want to learn, always show to the community you tries so far
3. Always use tags before and after your code to keep the code formatted on forum side
4. Post in the proper forum according to the question, in yuour case, <a href=PL/SQL & PL/SQL</a> (not Database General)
+=> thread moved there.+
Nicolas.
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koteravindra
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http://svangasql.wordpress.com/2012/04/10/simple-tips-to-speed-up-your-ssis-data-flow/
http://www.developer.com/db/top-10-methods-to-improve-etl-performance-using-ssis.html
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Give me the Example to join multiple tables 1
Inner join
IF p_bsart IS INITIAL.
SELECT ekko~bukrs
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Hi
Syntax
... [(] {dbtab_left [AS tabalias_left]} | join
{[INNER] JOIN}|{LEFT [OUTER] JOIN}
{dbtab_right [AS tabalias_right] ON join_cond} [)] ... .
Effect
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<---------- START QUOTE ---------->
RESEARCH
=========
Bug 3437036 KEY LOOKUP DOES NOT DETECT ORA-1417 IN VALIDATE/GENERATE STEP
Unpublished Bug 4211684 FORWARD PORT OF BUG 3437036
shows:
Some more development has been completed when this bug is fixed in Paris.
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ANSI syntax does not have the original problem the base bug of this
bug reported.
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<---------- END QUOTE ---------->
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Dear Oracle guru's
This is seems to be simple but i couldnt get it right.
I am exploring the features of Oracle 10g and try to implement it .
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I find this very easy ... but i have been asked to implement new things
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ssrYes, you really posted this in the wrong forum.
The Join operator is just a different way of restating the SQL that you have done before.
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I have set up JNDI bound datasources DS1 for DB1 and DS2 for DB2.
If the queries involved single tables or multiple tables within the same database, it is simple. But I am not seeing any way where I can perform a join between Tables A and B, which reside in separate databases. The datasources DS1 and DS2 are associated with DB1 and DB2 respectively, so I am not sure if there is anything like performing joins using two data sources.
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Thanks!Two choices..
One find the syntax in DB2 that allows you to do what you want in there. That would often be somelike...
select a.myfield
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Else?
Thanks to help.
ScottWill ORACLE first evaluate t1.status, t1.city, and t1.state first to eliminate the unmatched records, then make the join? OR
oracle will first make the join, then eliminate the unmatched records based on the t1.status, t1.city, and t1.state conditions? OR
Else?
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Here is three join method
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b) Sort-merge join.
In this case server process will sort both tables in the memory(in optimal variant) based on join columns and then merged these.
But here is also important access method. Which method oracle used for scanning OUTER or INNER tables? if this is FULL TABLE SCAN then it means oracle will read
all blocks of the table(under high water mark) and after that according FILTER option in execution plan oracle discard these rows. But if oracle choose INDEX RANGE scan then oracle will get need relevant rows using index and here will not any discarding(most cases) also you can see in execution plan like ACCESS word. -
Joining 2 tables in oracle database using SQL
I want to join 2 tables together before executing a statement.
problem is one is a table of users, who have userID's
and the othet table is a table of events that are owned by a userID, ie can have many events by same userID.
i want to retrieve forename and lastname from the users table, nd the event details from the event table, and put a name against each event rather than a userID, how can i do this?
note i want to extract EVERY SINGLE EVENT, and get the name of the user it is owned by via the userID
heres a example of a row
Table Users
| UserID | Forename | Surname |
| Y244850 | Jimmy | Conner |
| Y256738 | Mikey | Reeves |
Table Events
| UserID | Date | Type | Location |
| Y244850 | 07-Jan-01 | Holiday | Ibiza |
| Y244850 | 15-Dec-01 | Holiday | Jamaica |
------------------------------------------------Well just exchange user_id with u.user_ud or l.user_id:
SQL> SELECT forename, surname, TO_CHAR(id) id,
TO_CHAR(start_date) start_date, TO_CHAR(end_date)
end_date, type, u.user_id, location FROM leave_details l,
user_details u WHERE l.user_id = u.user_id;
When you just say select user_id, the database doesn't know wich user_id to use. The one in details or in users...
(Even though you and me know its the same)
So just be spesific and choose one.
Sjur -
Joining multiple tables using ANSI join
Hi,
I need to join 4 tables using ANSI join. Lets say they are A,B,C adn D. A and B has a common column called x. C and D had a common column called y. I wrote a query like this
select * from A left outer join B on (A.x=B.x),
C left outer join D on (C.y =D.y)
its not working!!!
I need to use ANSI join.
can any body help me please???Hi,
But is there is any common column between A,C or B,C or D,A?
Let me know. -
Joining multiple tables across multiple data sources in MYSQL throws error
Hi all,
I have to join tables across multiples MYSQL databases
eg :
Table T1,T2 from DB1
Table T3 from DB2
Columns from T3 are aggregated ( dimensional column ).
Hence when i query using oracle answers ( say i have columns from T1,T2 and T3 ) , OBIEE tries to a query DB1 by having NULL for columns in T3
It uses cast(NULL as INTEGER ) for columns from T3 . But MYSQL throws an error because "cast(NULL as INTEGER )" is not supported by MYSQL.
I tried executing the query generated by OBIEE manually , if i try giving cast(NULL as SIGNED INTEGER ) , it works.
pasting the query for reference
select distinct D1.c2 as c1,
D1.c1 as c2,
cast(NULL as INTEGER ) as c3
from
(select distinct T87.title_id as c1,
T59.asin as c2
from
print_book_catalog T59 left outer join
title_authority T87 On T59.asin = T87.asin
where ( T59.asin = '0345378911' )
) D1
I am not able to find any config file to set this property ( and use signed integer instead of integer ) . Even DBFeatures.INI does not have relevant information.
Can someobody please help me solve this problem.Stijn,
Thank you for the article link. That was very helpful! It seems that I had a few things off as you do need the "This source should be combined with other sources at this level." checked. In my two table source columns for DATA_SOURCE I defined a literal ('086496' and '085597' for the other) in the Column Mapping tab. I pasted the following in the Fragmentation content, checking the "This source..." box on the Content tab:
eSIS.SANDBOX4_SCHOOLS.DATA_SOURCE = '086496'
And pasted the following into the WHERE clause, checking "Select distinct values" on the Content tab:
sandbox4."".OBIEE.NWOCA_SCHOOLS.SCHOOL_CODE = VALUEOF(NQ_SESSION."SCHOOL") AND sandbox4."".OBIEE.NWOCA_SCHOOLS.DATA_SOURCE = VALUEOF(NQ_SESSION."GROUP")
This took care of my user's security, utilizing the session variables in the WHERE clause. I am now able to generate reports that only one user can access from one data source and share that same report with another user who can only see data from the other data source.
Many thanks!!!
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