Unique Index Created Automatically on FK Columns

Referencing the following document under Forward Engineering, http://www.oracle.com/technetwork/developer-tools/datamodeler/newfeatures30-224506.html
Unique index is created for One-to-one relationships defined in the Logical model if there is no PK/UK constraint or unique index defined over foreign key columns.
Why are unique indexes created automatically for foreign key columns? Should "lookups" not be defined in the logical model? I don't understand why it's designed to behave that way.

Why are unique indexes created automatically for foreign key columns? They are created automatically only for 1:1 relationships in order to support that business rule.
Should "lookups" not be defined in the logical model? Can you elaborate on that?
Philip

Similar Messages

Hi i have created a unique index on table on 3 columns.

Hi i have created a unique index on table on 3 columns.I want to know when i have 2 records
which contain same values in 2 fields and the 3rd field contains a null
will unique index allow me to insert these records.

Robert Angel wrote:
This must be one time when null = null. ;)
regards,
Robert.Not really, it is more the case that the non-null columns need to be unique. Your second attempt failed because there was already an index entry with 'a', 'b', and the lack of a value for column c gave Oracle no way to differentiate between the two rows so they are not unique.
A subtle, but conceptually important difference. :-)
John

Error while creating the Unique Index of the Primary Key of an Item

Hi all,
I have deployed a new item (CO_CONTRACTUNIT_PRODUCT) in my publication. The deploy appears to be successfull as the item can be seen in the repository through the Mobile Manager.
The problem occurs when i sync my local DB to get the item offline. While synchronizing, the following error appears, both in the sync window and the log file ol_sync.log.
"ERROR",POL-5130,"11/09/2010 11:43:52","table or view %s.%s not found:CO_CONTRACTUNIT_PRODUCT,CO_CONTRACTID,OD_PRODUCTID,CO_CONTRACTUNITID","DB_ROSHNI"
However, the debug file gives this other error regarding this table.
ALL_INDEX:CREATE UNIQUE INDEX "TPCO_CONTRACTUNIT_PRODUCT_PK" ON CO_CONTRACTUNIT_PRODUCT (CO_CONTRACTID,OD_PRODUCTID,CO_CONTRACTUNITID) -5130Error at C:\ADE\omeprod_ol103021\olite\db\build\win\ocapi\..\..\..\src\ocapi\allindexes.cpp line:329 rc:-5130
Build date Mar 29 2010
okErr=(table or view %s.%s not found)
mess=(CO_CONTRACTUNIT_PRODUCT,CO_CONTRACTID,OD_PRODUCTID,CO_CONTRACTUNITID)
AddLog(-5130 "ERROR",POL-5130,"11/09/2010 11:43:52","table or view %s.%s not found:CO_CONTRACTUNIT_PRODUCT,CO_CONTRACTID,OD_PRODUCTID,CO_CONTRACTUNITID","DB_ROSHNI")
But the index that is being created and is giving the error is the index created automatically with the Primary Key of the table, and so nothing has been modified in that.
The primary key of the table is created with the three columns that are part of the index that is returning the error.
As I could not solve the error, I tried to drop and re-create the item in the repository, but no luck. As a last option, i tried to remove the item from the repository to be able to sync properly again (just like before creating the item), but the error still happens.
Another weird point is that i have tried creating the item in another publication of another database (but with almost equal items), and the item could was downloaded to my local DB without any problem, which makes this problem still more bizarre.
What can it be?
Any help would be great!
Roshni

have you tried unistalling the client and reinstalling it?
schema evolution changes are not always handled correctly please check thread:
Modification of publication item into Mobile Server
i quote from rekounas instructions:
If you are just adding a field, you should only have to run the alter publication item API call.
Here is an old note on schema evolution on different scenarios. The names for the APIs that they use are now deprecated. Use the ConsolidatorManager class and call the method alterPublicationItem("PUBLICATION_ITEM_NAME", "SELECT STMT") :
A) Add column
1. Upload all client data. Clients should not add new data until they are told by the administrator to sync again!!
2. Stop Mobile Server listener
3. Change the Oracle8i/9i database schema (add column)
4. Create a Java program to call the Consolidator Admin API AlterPublicationItem()
5. Start Mobile Server
6. Execute a sync from the client
7. The new column should be seen on the client. Use MSQL to check snapshot definitions.
B) Drop column
1. Upload all client data. Clients should not add new data until they are told by the administrator to sync again!!
2. Stop Mobile Server listener
3. Delete column of the base table in the Oracle database schema
4. Create a Java program to call the Consolidator Admin API DropPublicationItem()
5. Create a Java program to call the Consolidator Admin API CreatePublicationItem() and AddPublicationItem().
6. Start Mobile Server
7. Execute a sync from the client
8. The new column should be seen on the cliet. Use MSQL to check snapshot definitions.
C) Change column datatype
Changing datatypes in a repliatated system is not an easy task. You have to follow certain procedures in order to make it to work. Use DropPublicationItem, CreatePublicationItem and AddPublicationItem methods from the Consolidator Admin API. You must stop/start Mobile Server listener to refresh the cache.
1. Client syncs. Clients should not add new data until they are told by the administrator to sync again!!
2. Stop Mobile Server listener
3. Drop/create column (do not use conversion procudures) at the base table
4. Call DropPublicationItem(). Check if the ErrorQueue and InQueue no longer exist.
5. Call CreatePublicationItem() and AddPublicationItem(). Check if the ErrorQueue and InQueue reflect the new column datatype
6. Start Mobile Server. This automatically resumes application
7. Client executes sync. This should drop the old snapshot and recreate the new snapshot. Use MSQL to check
snapshot definitions.
D) Drop table
1. Client syncs. Clients should not add new data until they are told by the administrator to sync again!!
2. Stop Mobile Server listener
3. Drop base table
4. Call DropPublicationItem(). Check if the ErrorQueue and InQueue no longer exist.
5. Start Mobile Server. This automatically resumes application
6. Client executes sync. This should drop the old snapshot. Use MSQL to check snapshot definitions.
E) Add table
1. Client syncs. Clients should not add new data until they are told by the administrator to sync again!!
2. Stop Mobile Server listener
3. Add new base table
4. Call CreatePublicationItem() and AddPublicationItem() method
5. Start Mobile Server. This automatically resumes application
6. Client executes sync. This should add the new snapshot. Use MSQL to check snapshot definitions.
F) Changing Primary Keys
Chaning PK is a severe operation which must be executed manually. A snapshot must be deleted and recreated to propagate the changes to the clients. This causes a full refresh on this snapshot.
1. Client syncs. Clients should not add new data until they are told by the administrator to sync again!!
2. Stop Mobile Server listener
3. Drop the snapshot using DropPublicationItem() method o
4. Alter the base table
5. Call CreatePublicationItem()and AddPublicationItem() methods for the altered table
6. Start Mobile Server. This automatically resumes application
7. Client executes sync. The old snapshot will be replaced by the new snapstot using a full refresh. Use MSQL to check snapshot definitions.
G) To Change a Table Weight =>
Follow the procedure below to change the Table Weight parameter. The table weight is used by the Mobile Server/Synchronization to determin the sequence in which client records are applied to the Oracle database.
1. Run MGP to apply any changes in the InQueue to the Oracle databse
2. Change table weight using SetTemplateItemMetadata() method
3. Add/change constraint on the the base table which reflects the change in table weight
4. Synchronize
gl m8

Unique Index Error while running the ETL process

Hi,
I have Installed Oracle BI Applications 7.9.4 and Informatica PowerCenter 7.1.4. I have done all the configuration steps as specified in the Oracle BI Applications Installation and Configuration Guide. While running the ETL process from DAC for Execution Plan 'Human Resources Oracle 11.5.10' some tasks going to status Failed.
When I checked the log files for these tasks, I found the following error
ANOMALY INFO::: Error while executing : CREATE INDEX:W_PAYROLL_F_ASSG_TMP:W_PRL_F_ASG_TMP_U1
MESSAGE:::java.lang.Exception: Error while execution : CREATE UNIQUE INDEX
W_PRL_F_ASG_TMP_U1
ON
W_PAYROLL_F_ASSG_TMP
INTEGRATION_ID ASC
,DATASOURCE_NUM_ID ASC
,EFFECTIVE_FROM_DT ASC
NOLOGGING PARALLEL
with error java.sql.SQLException: ORA-12801: error signaled in parallel query server P000
ORA-01452: cannot CREATE UNIQUE INDEX; duplicate keys found
EXCEPTION CLASS::: java.lang.Exception
I found some duplicate rows in the table W_PAYROLL_F_ASSG_TMP with the combination of the columns on which it is trying to create INDEX. Can anyone give me information for the following.
1. Why it is trying to create the unique index on the combination of columns which may not be unique.
2. Is it a problem with the data in the source database (means becoz of duplicate rows in the source system).
How we need to fix this error. Do we need to delete the duplicate rows from the table in the data warehouse manually and re-run the ETL process or is there any other way to fix the problem.

This query will identify the duplicate in the Warehouse table preventing the Index from being built:
select count(*), integration_id, src_eff_from_dt from w_employee_ds group by integration_id, src_eff_from_dt having count(*)>1;
To get the ETL to finish issue this delete to the W_EMPLOYEE_DS table:
delete from w_employee_ds where integration_id = '2' and src_eff_from_dt ='04-JAN-91';
To fix it so this does not happen again on another load you need to find the record in the Vision DB, it is in the PER_ALL_PEOPLE_F table. I have a Vision source and this worked:
select rowid, person_id , LAST_NAME FROM PER_ALL_PEOPLE_F
where EFFECTIVE_START_DATE = '04-JAN-91';
ROWID PERSON_ID
LAST_NAME
AAAWXJAAMAAAwl/AAL 6272
Kang
AAAWXJAAMAAAwmAAAI 6272
Kang
AAAWXJAAMAAAwmAAA4 6307
Lee
delete from PER_ALL_PEOPLE_F
where ROWID = 'AAAWXJAAMAAAwl/AAL';

UNIQUE INDEX and PRIMARY KEYS

Hi Friends,
I am confused about primary keys.
What is the purpose of this key again? I know it is used for unique constraints.
Supposing I have a table with two (2) columns which are each indexed as unique.
Then they can me both candidate at primary key right?
So why do I need a primary key again? when I have 2 columns which are uniquely index?
Thanks a lot

A UNIQUE index creates a constraint such that all values in the index must be distinct. An error occurs if you try to add a new row with a key value that matches an existing row. This constraint does not apply to NULL values except for the BDB storage engine. For other engines, a UNIQUE index allows multiple NULL values for columns that can contain NULL
The differences between the two are:
1. Column(s) that make the Primary Key of a table cannot be NULL since by definition; the Primary Key cannot be NULL since it helps uniquely identify the record in the table. The column(s) that make up the unique index can be nullable. A note worth mentioning over here is that different RDBMS treat this differently –> while SQL Server and DB2 do not allow more than one NULL value in a unique index column, Oracle allows multiple NULL values. That is one of the things to look out for when designing/developing/porting applications across RDBMS.
2. There can be only one Primary Key defined on the table where as you can have many unique indexes defined on the table (if needed).
3. Also, in the case of SQL Server, if you go with the default options then a Primary Key is created as a clustered index while the unique index (constraint) is created as a non-clustered index. This is just the default behavior though and can be changed at creation time, if needed.
So, if the unique index is defined on not null column(s), then it is essentially the same as the Primary Key and can be treated as an alternate key meaning it can also serve the purpose of identifying a record uniquely in the table.

Normal Indexes created for Primary/Unique Keys in Oracle8/8i

I remeber prior to Oracle8, when we create a Primary/Unique Key constraints, an unique index will be created by default. But I am noticing now in 8/8i when we create either Primary or Unique key, only normal/simple index is created. We are not able to override this normal index either by dropping and recreating the index alone. I believe it would be pretty much better in case of performance if we have a unique index for this columns. Can anybody help why is it changed so in 8/8i??
Thanks,
R. M.

Dear Rob,
since your answer was helpful and since it was the only one I will grant you full points on that.
Thanks again for your input. In case other developers should look this thread up being confronted
with the same kind of problem, here is how we solved it:
We added an artificial primary key (a number of type NUMC 8) to the table which is supposed to
include the structure. This key alone takes care of the uniqueness of eacht entry.
All the others fields that we want to have available for a fast direct access, including the ones
from the included structure, are put together in a secondary index.
best regards
Andreas

How to create an index for bi-lingual text column

I have a column that keeps the full file name of the attachment document file of a record. I need to build an index on the column so that we can search the attachment document file. The content of the file will be in English or French, but we don't know which one is in English and which one is in French. How I should build the index so that it will support 'contains' query and 'about' query for both English and French documents? What lexer, wordlist and stoplist I should use?
Here is something I am thinking:
lexer: basic_lexer
stoplist: build a custom stoplist that contains the stopwords for English and French.
wordlist: use the default for US should be OK since we don't need to support fuzzy and stem search.
The only problem is that it will only create the theme index properly for the English document but not the French document. This is because the NLS_LANG setting for the session is always in English. Therefore, the English knowledge base and lexicon will be used. I cannot use the THEME_LANGUAGE setting to overide it because I don't know the language of the document. Is there a way to merge the English knowleage base and lexicon with the French ones so that we can create a correct theme index without knowing the language of the document?
I am also thinking about using the multi_lexer. However, it won't help since we don't the language of the document.
Can anyone give me some help?
Thanks,
Wenjie
null

Creating a primary key, by definition, creates a (unique) index. Either inline at table creation, or via an alter table.
If its a composite PK, the alter table or inline constraint definition, after all the column declarations, is the only way to do it that I'm aware of.
create table t1 ( t1_pk number,
t1_desc varchar2(50),
constraint primary key t1_name_pk (t1_pk) [ using index tablespace <tblspc>]
-- or can constrain at the column def
create table t1 ( t1_pk number constraint t1_name_pk primary key ...,
-- or with an alter table. this won't work if there are non-unique entries
alter table t1 add ( constraint t1_name_pk primary key ( t1_pk [ index clause ] );The t1_name_pk constraint name can be optional, but if you don't include a constraint name the error messages are difficult to interpret, you get a system generated constraint name.
"... constraint <schema.>t1_name_pk violated ... " is much more informative than "... constraint <schema.>SYS_CNNNNNNNN violated ...".
The created index gets the same name used for the constraint as well.

Create unique index on flow table

Hi
I always get this error 'Create unique index on flow table ERROR" while implementing SCD2. Please help me.I have made an Update Key which is a combination of 4 columns that want a new row to be inserted if there is a change in data.One of the above columns is the EMPLOYEE ID,
My surrogate key is the table's primary key but I have not defined it as a key in mapping and also I have turned off the Primary Key Constraint Option in Controls Panel as NO.
Where am I wrong? Also please tell me what to take care off while making Natural Key ?

There are two solutions:
1. Only use uppercase in the table name
2. go in Topology>Physical Architecture and edit the technology, then click on
the "Language" tab and set "Object Delimiter" to empty.
Thanks,
Sutirtha

Creating an unique index instaed of using primary key index

Hi ,
I heard in a debate sometimes it's better to create a unique index on a column and using it instaed of using primary key index in oracle.I couldn't understand what the reason propely.
Can anyone please help me in thsi topic if it is a valid one .
Thanks in advance

Hi,
They are exactly NOT identical.
1. Unique key can have NULL values where primary keys can't.
2. Primary key is fundamentally those keys which do not change. I mean updating a primary key is not a good idea.
SQL> drop table test;
Table dropped.
SQL> create table test ( a number(2));
Table created.
SQL> ed
Wrote file afiedt.buf
1* create unique index test_idx on test(a)
SQL> /
Index created.
SQL> ed
Wrote file afiedt.buf
1* insert into test values(NULL)
SQL> /
1 row created.
SQL> drop table test;
Table dropped.
SQL>
SQL> create table test ( a number(2) primary key);
Table created.
SQL> insert into test values(NULL);
insert into test values(NULL)
ERROR at line 1:
ORA-01400: cannot insert NULL into ("HR"."TEST"."A")
SQL>Cheers,
Edited by: Avinash Tripathi on Nov 24, 2009 11:17 AM

Index created with DESC having USER_IND_COLUMNS.COLUMN='SYS_NC00023$'

On Oracle 11.2, I observed below
create index ind_jperson_1 on d_jperson(convict_ref);
create index ind_jperson_2 on d_jperson(driver_ref DESC);
select index_name,table_name,column_name,column_position,descend
from USER_IND_COLUMNS where table_name='D_JPERSON'
INDEX_NAME     TABLE_NAME     COLUMN_NAME     COLUMN_POSITION     DESCEND
IND_JPERSON_2     D_JPERSON     SYS_NC00023$     1     DESC
IND_JPERSON_1     D_JPERSON     CONVICT_REF     1     ASCHow to find the exact table column for this index?

user623617 wrote:
Surprise that DESC cause FBI. Then in what case will Oracle use it? The condition name='SMITH' will not use an index on upper(name). Need to use upper(name)='SMITH' to use the index.
To use in dex on upper(name) you need to crete FBI on upper(name).
Similarly if I have an index on (name desc), whould condition name='SMINTH' use the index.Yes, but at a higher cost than regular index (see access & filter):
SQL> create index emp_idx1 on emp(ename desc);
Index created.
SQL> explain plan for
2 select ename from emp where ename = 'SMITH';
Explained.
SQL> @?\rdbms\admin\utlxpls
PLAN_TABLE_OUTPUT
Plan hash value: 654424206
| Id | Operation        | Name     | Rows | Bytes | Cost (%CPU)| Time     |
|   0 | SELECT STATEMENT |          |     1 |     6 |     1   (0)| 00:00:01 |
|* 1 | INDEX RANGE SCAN| EMP_IDX1 |     1 |     6 |     1   (0)| 00:00:01 |
Predicate Information (identified by operation id):
PLAN_TABLE_OUTPUT
   1 - access(SYS_OP_DESCEND("ENAME")=HEXTORAW('ACB2B6ABB7FF') )
       filter(SYS_OP_UNDESCEND(SYS_OP_DESCEND("ENAME"))='SMITH')
14 rows selected.
SQL>
Another question, if I have two indexes on both person(name asc) and person(name desc), what index Oracle will use when " where name='SMITH' "?
Unless you use INDEX_DESC hint, optimizer will use ASCindex since it has lower cost (Other decision affecting factor could be order by name desc):
SQL> create index emp_idx2 on emp(ename asc);
Index created.
SQL> explain plan for
2 select ename from emp where ename = 'SMITH';
Explained.
SQL> @?\rdbms\admin\utlxpls
PLAN_TABLE_OUTPUT
Plan hash value: 3999498872
| Id | Operation        | Name     | Rows | Bytes | Cost (%CPU)| Time     |
|   0 | SELECT STATEMENT |          |     1 |     6 |     1   (0)| 00:00:01 |
|* 1 | INDEX RANGE SCAN| EMP_IDX2 |     1 |     6 |     1   (0)| 00:00:01 |
Predicate Information (identified by operation id):
PLAN_TABLE_OUTPUT
   1 - access("ENAME"='SMITH')
13 rows selected.
SQL> explain plan for
2 select /*+ index_desc(emp) */ ename from emp where ename = 'SMITH';
Explained.
SQL> @?\rdbms\admin\utlxpls
PLAN_TABLE_OUTPUT
Plan hash value: 2940971887
| Id | Operation                   | Name     | Rows | Bytes | Cost (%CPU)| Time     |
|   0 | SELECT STATEMENT            |          |     1 |     6 |     1   (0)| 00:00:01 |
|* 1 | INDEX RANGE SCAN DESCENDING| EMP_IDX1 |     1 |     6 |     1   (0)| 00:00:01 |
Predicate Information (identified by operation id):
PLAN_TABLE_OUTPUT
   1 - access(SYS_OP_DESCEND("ENAME")=HEXTORAW('ACB2B6ABB7FF') )
       filter(SYS_OP_UNDESCEND(SYS_OP_DESCEND("ENAME"))='SMITH' AND
              SYS_OP_DESCEND("ENAME")=HEXTORAW('ACB2B6ABB7FF') )
15 rows selected.
SQL> SY.

Create Unique Index On Flow does not work for table names 23 characters

I have a "create unique index on flow table" step that is dynamically generated by the IKM.
The index name that is generated by the IKM is based on the table name except that the created index name is prefixed with "I$_" and ends with "_idx". Obviously, since Oracle table names can not exceed 30 characters in length, the index creation step will fail if the base table name exceeds 23 characters.
I have tried to substring the index name generation step in the IKM so that it only uses the first 23 characters of the table name, but have not had any luck with using the "substring" command together with snpRef.getTable call.
This is the section of the IKM that I desire to change:
- <Field name="Txt" type="java.lang.String">
- <![CDATA[
create unique index      <%=snpRef.getTable("L","INT_NAME","W")%>_idx
on          <%=snpRef.getTable("L","INT_NAME","W")%> (<%=snpRef.getColList("", "[COL_NAME]", ", ", "", "UK")%>)
<%=snpRef.getUserExit("FLOW_TABLE_OPTIONS")%>
]]>
</Field>
I would like to change the above to something similar to the following (note the only change is the addition of substring(1,23))
- <Field name="Txt" type="java.lang.String">
- <![CDATA[
create unique index <%=snpRef.getTable("L","INT_NAME","W")*.substring(1,23)*%_idx
on          <%=snpRef.getTable("L","INT_NAME","W")%> (<%=snpRef.getColList("", "[COL_NAME]", ", ", "", "UK")%>)
<%=snpRef.getUserExit("FLOW_TABLE_OPTIONS")%>
]]>
</Field>
Any help greatly appreciated. Thanks.

As the index is temporary, just like the I$ talbel, the easiest way is to replace the table name with some unique identifier like the session is:
bq. I$_<%=odiRef.getSession("SESS_NO")%>_idx
If for some reason that is not unique enough, add the NNO:
bq. I$_<%=odiRef.getSession("SESS_NO")%><%=odiRef.getSession("NNO")%> \\ _idx

Can an unique index be created on read only cache group

Hi
Can an unique index be created on read only cache group
Regards
Siva Kumar

No, I do not think so. Creating a unique index could cause autorefresh operations to fail if the data being refreshed contains duplicate values that would not be allowed by the index. You can create regular indexes on a table in a readonly cache group.
Chris

Create unique index from duplicate rows

Dear
I created an index like
create index tablename_idx on tablename (FIELD1,FIELD2);
It should be
create unique index tablename_idx on tablename (FIELD1,FIELD2,filed3);
How can I delete those duplicate records and create the UNIQUE index ?
Thanks and regards
Fahmed

> How can I delete those duplicate records
[url http://forums.oracle.com/forums/search.jspa?threadID=&q=delete+duplicate+records&objID=f75&dateRange=all&userID=&numResults=15]http://forums.oracle.com/forums/search.jspa?threadID=&q=delete+duplicate+records&objID=f75&dateRange=all&userID=&numResults=15
Regards,
Rob.

Create automatic indexing( id) in the DB

what snippet should i use to create automatic indexing( id) in the DB ?
like
1
2
3
4
5...
not by count++ but by triggering DB ...how it is done ?

what snippet should i use to create automatic
indexing( id) in the DB ?
like
1
2
3
4
5...
not by count++ but by triggering DB ...how it is done
?Depends on the database. Some databases have SEQUENCE types, which you manipulate via SQL statements; others have IDENTITY or AUTOINCREMENT (?)types of field attributes, which automatically increment when you insert a row.

Feature that automatically creates a list and columns

Hi,
I wanted to create a feature that automatically creates a list and columns programatically. Can anyone please help me how to implement this.
Regards,
Praveen

Please check below article to create columns and list programatically
http://www.sharepointdoug.com/2012/12/programmatically-creating-content-type.html
similar thread below to create list programatically
https://social.msdn.microsoft.com/Forums/sharepoint/en-US/2d82a8fd-052c-4d24-bfef-3ff59986b29c/how-to-create-custom-list-in-sharepoint-2010-programmatically-?forum=sharepointdevelopmentprevious
My Blog- http://www.sharepoint-journey.com|
If a post answers your question, please click Mark As Answer on that post and Vote as Helpful

Unique Index Created Automatically on FK Columns

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