Dbtable without a primary key

hi!
is it possible to create a db-table without a primary key? if there is a possbility, how can i do this?
greetings
stefan

Hello,
The link i provided contains all your answers. Its oracle 8i documentation release. It contains everything that you want to know about oracle 8i release.
What Are Index-Organized Tables?
Index-organized tables are tables with data rows grouped according to the primary key. This clustering is achieved using a B-tree index. B-tree indexes are special types of index trees that differ from regular table B-tree indexes in that they store both the primary key and non-key columns. The attributes of index-organized tables are stored entirely within the physical data structures for the index.
Why Use Index-Organized Tables?
Index-organized tables provide fast key-based access to table data for queries involving exact match and range searches. Changes to the table data (such as adding new rows, updating rows, or deleting rows) result only in updating the index structure (because there is no separate table storage area).
Also, storage requirements are reduced because key columns are not duplicated in the table and index. The remaining non-key columns are stored in the index structure.
Index-organized tables are particularly useful when you are using applications that must retrieve data based on a primary key. Also, index-organized tables are suitable for modeling application-specific index structures. For example, content-based information retrieval applications containing text, image and audio data require inverted indexes that can be effectively modeled using index-organized tables.
See Also: For more details about index-organized tables, see Oracle8i Concepts.
Differences Between Index-Organized and Regular Tables
Index-organized tables are like regular tables with a primary key index on one or more of its columns. However, instead of maintaining two separate storage spaces for the table and Btree index, an index-organized table only maintains a single Btree index containing the primary key of the table and other column values.
Index-organized tables are suitable for accessing data by way of primary key or any key that is a valid prefix of the primary key. Also, there is no duplication of key values because a separate index structure containing the key values and ROWID is not created. Table 14-1 summarizes the difference between an index-organized table and a regular table.
Table 14-1 Comparison of Index-Organized Table with a Regular Table
Regular Table Index-Organized Table
ROWID uniquely identifies a row; primary key can be optionally specified
Primary key uniquely identifies a row; primary key must be specified
ROWID pseudo-column refers to physical block address
ROWID pseudocolumn refers to primary key-based logical ROWID
Secondary indexes store physical data
Secondary indexes store primary key-based logical ROWID
Can be stored in a hash or index cluster
Cannot be stored in a hash or index cluster
Regards,
Shekhar Kulkarni

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http://technet.microsoft.com/en-us/library/ms191517(v=sql.105).aspx
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Hi Fusion777,
Ya, I've been searching around forums for an answer also. Apparently this is indeed a problem that has no general solution. It depends on 2 factors:
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<automatic-key-generation>
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</automatic-key-generation>
<automatic-key-generation>
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</automatic-key-generation>I've tried that and it works :-)
I gather from your reply that those who are using JBoss are equally fortunate :-)
So I thought I'll share this in case some other poor fellow is facing the same problem as we are. At least worse come to worse, he'll have the option of switching to either JBoss or Weblogic and know that it works in both :-)
Some other users seem to be against the idea of using auto-generated keys for precisely the reason that it is not a standard across database and application servers. See this thread:
http://forum.java.sun.com/thread.jspa?forumID=13&threadID=329896
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You can check out Hibernate at http://www.hibernate.org.

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CREATE MATERIALIZED VIEW mv_minidrr ...
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Well, there indeed is a column called M_ROW$$
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SQL> desc mlog$_emp
Name                                                  Null?    Type
M_ROW$$                                                        VARCHAR2(255)
SNAPTIME$$                                                     DATE
DMLTYPE$$                                                      VARCHAR2(1)
OLD_NEW$$                                                      VARCHAR2(1)
CHANGE_VECTOR$$                                                RAW(255)
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Creating a snapshot without primary keys

Hi,
I would like to create a snapshot for a table that does not have a primary key. I've read the thread
"Re: creating snapshots without a primary key??"
from Mar 24, 2003, which seems to indicate that this is allowed if the snapshot is not updatable. However, even when I disable the "Updatable?" option, I still get the following error:
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CONS-10032: Publication item: WTGPI_10012 cannot
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This check box defines the snapshot to be created
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That description has a lot of unmet potential.
Thanks,
Tim

Hello,
If you create a snapshot that has no primary key, you have to check the option "complete refresh".
Oracle uses the primary key to track changes for the "partial refresh" option (only send changes back and forth).
-Antti Virkkunen, www.vilant.com

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Hi,
Can we implement Change Data Capture in Oracle 10g without having Primary Key at the source level.
With Regards,
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Hi;
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Hi All,
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I have not event put my main DB in force logging mode. This is because, redo log files or standby redo logfiles transforms into set of sql statements to update logical standby.
Have you done any DML operations with nologging options and do you notice any errors in the alert.log? I just curious to know.
But I wanted to know that, while system tablespace in hot backup mode,In the absence of both a primary key and a nonnull unique constraint/index, all columns of bounded size are logged as part of the UPDATE statement to identify the modified row. In other words, all columns except those with the following types are logged: LONG, LOB, LONG RAW, object type, and collections.
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Can EJB 3.0 beans be used with tables that do not have a primary key?

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The spec requires a primary key Id annotation. I will take your suggestion to EJB 3.0 expert group.
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hi,
I am reading chapter 10 of expert oracle database architecture by tom kyte, and I am getting a little confused. It seems to me as if he is saying that an IOT should be built using the PK of that table. What if our table does not have a PK?
thanks

OracleGuy777 wrote:
hi,
I am reading chapter 10 of expert oracle database architecture by tom kyte, and I am getting a little confused. It seems to me as if he is saying that an IOT should be built using the PK of that table. What if our table does not have a PK? Then you can not create an IOT. It's a rule. http://download.oracle.com/docs/cd/B28359_01/server.111/b28318/schema.htm#i23877
One of the suggestions is 'try it'. So let us do exactly that - create 2 nearly idetical IOTs - one with and the second without a primary key
SQL*Plus: Release 10.2.0.1.0 - Production on Sun Nov 1 11:07:37 2009
Copyright (c) 1982, 2005, Oracle. All rights reserved.
Connected to:
Oracle Database 10g Express Edition Release 10.2.0.1.0 - Production
SQL> CREATE TABLE countries_demo
2      ( country_id      CHAR(2)
3        CONSTRAINT country_id_nn_demo NOT NULL
4      , country_name    VARCHAR2(40)
5      , currency_name   VARCHAR2(25)
6      , currency_symbol VARCHAR2(3)
7      , region          VARCHAR2(15)
8      , CONSTRAINT    country_c_id_pk_demo
9                      PRIMARY KEY (country_id ) )
10      ORGANIZATION INDEX
11 /
Table created.
SQL> edit
Wrote file afiedt.buf
1 CREATE TABLE countries_demo2
2      ( country_id      CHAR(2)
3        CONSTRAINT country_id_nn_demo NOT NULL
4      , country_name    VARCHAR2(40)
5      , currency_name   VARCHAR2(25)
6      , currency_symbol VARCHAR2(3)
7      , region          VARCHAR2(15) )
8*     ORGANIZATION INDEX
SQL> /
    ORGANIZATION INDEX
ERROR at line 8:
ORA-25175: no PRIMARY KEY constraint found
SQL>SO the conclusion is, whether it makes sense to us or not, we can not create a table without defining a primary key.
It makes sense to me, since the IOT is actually stored as a unique index with nulls not allowed - for which a PK is a perfect fit. Note that a PK COULD be defined with multiple columns instead of the traditional single column (and often wrong surrogate key)

Source tables for forms and tabular forms must have a primary key.

Why does HTML DB 2.0 return the message
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when trying to generate a "Report and Form" page based on a view defined like "create view <applicationschema>.a as select * from <sourceschema>.b" ?
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bw - Christian

Christian,
In the create application wizard, when creating form or tabular form pages, you can only use tables with primary keys, and not views, because that wizard is automatically deriving the primary key from the table definition. If you want to build forms on views or tables without a primary key, you need to use one of the create form wizards while working on an existing application. Those wizards allow you to pick your own column as a primary key column.
Regards,
Marc

Unable to enforce Primary Key constraint with my code

Hi Guys
I have a table that contains 2 columns: code and description (defined as not null). I am using oracle forms 10g, if I inset a new row both the columns: code and description should have data e.g. code: 001 and description: Main Store...
So on forms I have an on-update trigger on block level that handles the error messages but if the user has to update the description this trigger blocks him because the value for the code i.e. 001 is already on the database but if I remove the piece of code (the first IF block on my code together with a cursor and the entire declaration section)then the primary key constraint is violated: the code is as follows:
declare
v_store_code store_types.code%type;
cursor store_codes is
select a.code
from store_types a
where a.code = :b1.code;
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open store_codes;
fetch store_codes into v_store_code;
if ( store_codes%found ) then
Message('The Store Code you have entered already exists on the Store_Types table, please enter another code!');
Message('The Store Code you have entered already exists on the Store_Types table, please enter another code!');
close store_codes;
raise form_trigger_failure;
end if;
close store_codes;
if :b1.code is not null and :b1.description is null then
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     message('If the Store Code has been captured, then the Store Description must be captured!');
raise form_trigger_failure;
end if;
if :b1.description is not null and :b1.code is null then
     message('If the Store Description has been captured, then the Store code must be captured!');
     message('If the Store Description has been captured, then the Store code must be captured!');
     raise form_trigger_failure;
end if;
exception
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               message(sqlerrm);
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end;
My main intention here is: the user should be able to update the description field and save the changes without violating primary key on the column: code ...... please help me guys...

ICM
Sir as far I could understand , your problem is that your wanna allow the end users to update the Store_description , and Store_code..
So on forms I have an on-update trigger on block level that handles the error messages but if the user has to update the description this trigger blocks him because the value for the code i.e. 001 is already on the databaseif it's right then why don't you have unique key constraints Store_description?
alter the tables and apply unique key constraint...
and no need to write this code
f :b1.code is not null and :b1.description is null then
message('If the Store Code has been captured, then the Store Description must be captured!');
message('If the Store Code has been captured, then the Store Description must be captured!');
raise form_trigger_failure;
end if;because as you mentioned
code and description (defined as not null)if they are already under not null constraints then no need to handle this in coding..
he/she must be able to change the description and save the changes without affecting the code i.e.:Sir I think updation in records can only be performed when the forms is in query mode e.g execute query, have all/desired records and then make changes
(1)description is in unique key constraint it can't be duplicated ..
(2)code is PK it can never be duplicated...
for this I would suggest you to have a update button on forms , when-button-pressed trigger sets property of block (update_allowed, property_true);
and check the code of unique key violation code from oracle form's help , when that error code raise up you can show those message
Message('The Store Code you have entered already exists on the Store_Types table, please enter another code!');
Message('The Store Code you have entered already exists on the Store_Types table, please enter another code!');I hope it could do something for you
thanks
regards:
usman noshahi

Inner join-select -primary key in table issue

Hi ,
Iam using FEBKO(header) and FEBEP(item) in inner join select .But the datas fetching by this selct in not correct.The analysis is the is no common primary fields in the both table.
Question 1-> Can i use inner join without common primary key in the both tables, weather it possible to make a select without common primary key in both table. Please kindly let me know.
Question 2-> What is the other possible way to give the selct for both table(better performance)
Regards,
Veera

Hi,
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Hope this is helpful to you. If you need further information, revert back.
Reward all the helpful answers.
Regards
Nagaraj T

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