reverse the primary key index

Similar Questions

• creating a unique index of instaed of using the primary key index

  Hello
  
  I heard in a debate sometimes it is better to create a unique index on a column and use it instead of using the primary key index in oracle. I did not understand what that the reason propely.
  
  Can someone please help me in this topic if it is valid.
  
  Thanks in advance

  On the surface, which does not seem reasonable... Volume of the DML is irrelevent to determine which column is the primary key for a table.

  My wild speculation a bit at a reasonable time could someone do...

  If you use synthetic primary keys (i.e. the keys generated by sequence) and that your tables are subject to large volumes of inserts such as there is a danger that the block "to the right" will be the source of contention block and worry not about analysis of beach on the column, you can create a reverse on this column (unique or non-unique) key index before creating the primary key constraint and to indicate Oracle to use this existing index to respect the primary key constraint.

  Obviously, however, this involves a lot of assumptions to arrive at a reasonable point. There may well be another set of assumptions that could also lead to a valid argument. Or it could be a myth that someone has heard and just repeats.

  Justin

• Factor of clustering for the primary key Index

  Hi all
  
  I have cretead a new table with 1.7 million records with an index of primary key on ID (NUMBER)
  Number of blocks used is arnd 57 K.
  
  Factor value of clustering on the primary key index is 1.6 million.
  
  Could you please suggest what can be the reason for such a clustering factor high for the new table.
  
  
  Thank you
  Ash N.

  Google is your friend:
  http://www.dbasupport.com/forums/archive/index.php/t-38893.html
  http://asktom.Oracle.com/pls/asktom/f?p=100:11:0:P11_QUESTION_ID:1032431852141
  http://hemantoracledba.blogspot.com.es/2008/01/impact-of-clustering-factor.html

• Performance problem on the SQL query that does not use the primary key index

  Hello!
  
  I have some performance issues on a single SQL query (Oracle 10 g).
  I could solve the problem by using the INDEX indicator, but I would like to know WHY this is happening.
  
  * Tables *.
  create table jobs)
  ID number (5) not null,
  name varchar2 (100),
  primary key constraint Job_PK (id)
  )
  /
  -Record count: 298
  
  create table Comp)
  integer ID not null,
  name varchar2 (100),
  primary key constraint Comp_PK (id)
  )
  /
  -Record count: 193
  
  -Relation m: n
  create table JobComp)
  integer ID not null,
  id_job integer not null,
  id_comp integer not null,
  primary key constraint JobComp_PK (id),
  unique key constraint JobComp_UK (id_job, id_comp),
  Constraint JobComp_FK_Job foreign key (id_job) refers to Job (id),
  Constraint JobComp_FK_Comp foreign key (id_comp) makes reference Comp (id)
  )
  /
  create index JobComp_IX_Comp on JobComp (Cod_Comp)
  /
  create index JobComp_IX_Job on JobComp (Cod_Job)
  /
  -Record count: 6431
  
  * Ask *.
  
  When I run this query, the execution plan shows the index using (JobComp_PK and JobComp_IX_Comp).
  No problem.
  
  Select JobComp.*
  of JobComp
  Join jobs
  on Job.id = JobComp.id_job
  where JobComp.id_comp = 134
  /
  -runs in 0.20 sec
  
  But when I add the field 'name' of the work table the plan uses full access table to the table of work
  
  Select JobComp.*, Job.name
  of JobComp
  Join jobs
  on Job.id = JobComp.id_job
  where JobComp.id_comp = 134
  /
  -runs in the 2.70 dry
  
  With the help of the index
  
  Select / * + INDEX (Job Job_PK) * /.
  JobComp.*, Job.name
  of JobComp
  Join jobs
  on Job.id = JobComp.id_job
  where JobComp.id_comp = 134
  /
  -runs in 0.20 sec
  
  * Doubt *.
  
  This behavior is correct?
  
  PS. : I tried to recalculate the statistics, but nothing changes:
  
  analyze the job calculation table statistics.
  /
  change the statistical calculation of index Job_PK reconstruction;
  /
  Start
  dbms_utility.analyze_schema (sys_context ('userenv', 'current_schema'), 'CALCULATE');
  end;
  /
  
  [of]
  Gustavo Ehrhardt

  Gus.EHR wrote:
  Hello.
  I'm sorry for the plan unformatted.
  The execution time of the querys "without field name' and 'with the field name with suspicion" are equal.
  He has no problem caching, because I get the plans of the sequence different from the querys and repeated the performance. The result is always the same.

  I don't think that there is no problem with oracle crossing LOOP IMBRIQUEE to the HASH JOIN when you include the field name and this should be the expected behavior. But it seems that your WORKING table has a degree of parallelism set against what is causing the query to run in parallel (as JOB table is now available with full table scan, instead of indexed access earlier). It could be that the parallel execution is contributor to extra Runtime.
  (a) do you know why the degree of parallelism on the WORK table has been defined? Do you need it?

  You can see if the following query provides a better response time?

  select /*+ NOPARALLEL(JOB) */ JobComp.*, Job.Name
    from JobComp
    join Job
      on Job.id = JobComp.id_job
   where JobComp.id_comp = 134
  

• old age and the primary key index

  That question lingers on me for a long time. When I have a table(non-partitioned) with A column as a primary key, it makes no difference (in data retreival) if I create an index on column A. The oracle that I use is 10.2.0.3. My conclusion was pk already stores records in a sorted order and an index is not necessary.
  
  I also have a question on the index in the global temporary tables. A global temporary table was created initially with his index finger. Then, it is used with each session. As the data in a global temporary table are related to the session, oracle create index separated for each session?

  Hello

  When you create an on a column in a table's primary key, a unique index is created automatically, you need not create separate.

  Oracle Concepts:

  You can create indexes for temporary tables using the CREATE INDEX statement. Indexes created in the temporary tables are also temporary, and the data in the index have the same scope of session or transaction data in the temporary table.

  You can create views that access the temporary and permanent tables. You can also create triggers on temporary tables.

  For more information, see [temporary Tables | http://download.oracle.com/docs/cd/B19306_01/server.102/b14220/schema.htm#sthref769]

  Kind regards

  Published by: Walter Fernández on February 7, 2009 22:09 - Add URL...

• Problem with the primary key and indexes

  Hi all
  
  I'm looking a mess on one of our main tables.
  One of the developers here added an index on 3 columns in the table, thinking that it would speed up (not noticing that it had not a PK).
  
  Subsequently another developer has noticed there do not have a primary on key. So they added a touch of primry on the single column.
  
  The problem is that now the index created on 3 columns is bein used as the primary key index. As when the primary key is created a new index was not created.
  
  Is there anyway to get rid of this index/change it correct?
  
  This table is related to many many other tables, so when we tried to remove the index we could not due to the primary key and foreign key violations with other tables.
  
  Thanks in advance

  Oracle, as you found, is quite capable to use a column enformce multi index a single column primary key, as long as the pk column is the leader in the index. This should not cause performance issues for a search of PK and if the three indexed columns are often selected only may benefit from these types of queries.

  The only way to change that now, would be to drop all CF, drop and add the PK constraint and then add all the FK constraints. A long time and potentially dangerous (if you miss to add back of the FKs) endeavour. Certainly not worth the risk in my opinion.

  John

• The index of the primary key in a different tablespace.

  Hello
  
  I have a user PROD. It has received a tablespace PROD_TBS default.
  There is a separate table for all indexes space in the diagram, PROD_IDX.
  
  I want to create a TEST table as follows,
  
  CREATE TABLE TEST
  (TEST_ID, NUMBER (1),)
  NAME VARCHAR2 (10));
  
  It must be a primary key on the column test_id, but such that the corresponding unique index created by default because of the primary key must be created in the PROD_IDX tablespace.
  
  How to do this?

  Alternative solution:

  CREATE TABLE TEST
  (TEST_ID NUMBER(1),
  NAME VARCHAR2 (10),
  constraint test_pk primary key (test_id)
  using index tablespace prod_idx
   );
  

  Cheers, APC

  blog: http://radiofreetooting.blogspot.com

• How did the foreign key that is recognized by the primary key

  Hi, when I have two user tables and userLevel and the primary key of the user is the user name and I add a field to userLevel userID is only to make the userID field in userLevel automatically the foreign key of the table? Or do you switch the engine of MyISAM tables to InnoDB to make relational links. Can someone please explain this in English clear to me, because I just can't get my head around this.

  In the case of a query such as SELECT statement, we talked, being a key actually means that the field is indexed so that the database can quickly look up.  Thus, in phpMyAdmin, you set the field to be indexed by the visualization of the structure of the table and clicking the icon index (the one with the Lightning) for the field in the Action section.

  If you are looking for integrity refrential between tables we also talked about and using the InnoDB engine, you can click the link 'Show the relational' in the table structure page of phpMyAdmin and define foreign key constraints.

• APEX do not allow to change the lines of the columns that are the primary key?

  I have pictures:
  http://img508.imageshack.us/my.php?image=21269582oe8.jpg
  
  
  Book (id_book - 'Primary key', title, year); book_author (id_author id_book - 'Primary key', - 'Primary key'); author (id_author - "Primary key", name)
  
  
  
  I created a new page-> Form-> form of 'author' table because I want to add new authors, modification and deletion. During the creation of this page, I have chosen column 'id_author' as '1 primary key column' and everything is OK (I can't edit the 'id_author' column - this column is autoincrement and I can change the 'name' column).
  
  BUT I also created a new page-> Form-> table for table "book_author" because I like to write numbers like id_book and id_author, change and remove them (so add relations between tables: book, book_author and author). During the creation of this page, I have chosen column 'id_book' as '1 primary key column' and 'id_author' as 'column primary key 2'. And on the Web site, I can't edit these fields. And I can not add also new line because I see in each new line: (null).
  
  http://img444.imageshack.us/my.php?image=11324615yk9.jpg
  
  APEX do not allow to change the lines of the columns that are the primary key? It's stupid... What can I do?
  
  Edited by: user10731158 2008-12-20 11:40

  Column unique and not meaningful if you ever want to update. In the case of your example, you need to add an ID column in the intersection of book_author table. Honestly, I was so blown away (and pleasantly surprised) by the absence of rebuttal and the "thx" I advanced and set up an example of how I would define the book_author table:

  create table  book_author
     (id varchar2(32),
      book_id varchar2(32),
       author_id varchar2(32),
       modified_on     date,
       modified_by varchar2(255),
       constraint book_author_pk primary key (id),
       constraint book_auth_book_fk foreign key (book_id) references books(id),
       constraint book_auth_author_fk foreign key (author_id) references authors(id)
       )
  /
  
  create unique index book_author_uq on book_author (book_id,author_id)
  /
  
  create or replace trigger  biu_book_author before insert or update on book_author
  for each row
  begin
       if inserting then
            :new.id := sys_guid();
       end if;
       modified_on := sysdate;
       modified_by := nvl(v('APP_USER'),user);
  end;
  /
  

  Good luck
  Tyler

• How to find the primary key columns in the tables in MS Access using SQL queries

  How to find the primary key columns in the tables in MS Access using SQL queries

  Hello

  This is the forum for Windows Vista programs related issues.

  For better assistance, please try instead the Forums in SQL Server .

  Thank you! Vincenzo Di Russo - Microsoft MVP Windows Internet Explorer, Windows Desktop Experience & security - since 2003. ~ ~ ~ My MVP profile: https://mvp.support.microsoft.com/profile/Vincenzo

• Make required error appears only the primary key generated in prior Database Table insert trigger

  Dear all,

  I am a beginner in the ADF and am under Jdeveloper Studio Edition Version 12.2.1.0.0.

  
  

  I'm trying to insert a record, I created the trigger for insertion prior to get the primary key and set some other default values.

  
  

  On the page, I did read-only primary key column and false required.

  
  

  When I try to save - commit (Programmatic), I get errors for the required value. How can I stop this errors.

  
  

  Secondly, I also tried changing the agent to disabled on the attribute View object that raised the error below:

  
  

  < oracle.dfw.impl.incident.DiagnosticsDataExtractorImpl > < DiagnosticsDataExtractorImpl > < createADRIncident > < incident created 148 to key problem "DFW-99998 [oracle.jbo.PersistenceException] [oracle.jbo.server.RowReference.verifyPrimaryKeys] [Proposals]" >

  
  

  Hoping for help.

  
  

  Thanks and greetings

  
  

  Arif Khadas
  

  If the primary key values from DB sequence, you can follow this approach:

  Using the sequence of database in ADF - Souza Waslley Blog

  Oracle Fusion Middleware Technologies: ADF 11 G: generate the primary key sequence number

  Otherwise, instead of DB trigger, create the DB function that retrieves the value of the PK and call stored function in the overloaded method create() entity:

• Houston-25013: too many objects match the [primary key Lookup.USR_PROCESS_TRIGGERS USR_EMP_TYPE] oracle.jbo.Key.

  Hello

  I am trying to open the Console of the IOM of Sysadmin,

  try checking the research,

  search specific "Lookup.USR_PROCESS_TRIGGERS".

  and get the error on the screen

  Houston-25013: too many objects match the [primary key Lookup.USR_PROCESS_TRIGGERS USR_EMP_TYPE] oracle.jbo.Key.

  This known issue?

  This patch it for it?

  tried searching discussion forums, nothing here

  Thank you

  Check from the console design.  Looks like you have a duplicate key Code value.

  -Kevin

• Comparison of the data of several rows in a table - based on the primary key

  Currently I have a select statement that returns hundreds of records.  Each returned record is linked to A NUMBER of ORDER this order number has a recipe.  (a bit like a cooking recipe).  Each recipe has many records in the database related to this order number and records should be compared to records in a table that bind to a specific primary key...  (I have already developed the logic to isolate what PK I need).  If all these records that are returned by the select statement below does not match all the records containing PK in the table below, I need to get the next PK and compare all these recordings for select statements return.

  See below for a better understanding. Need a good example detailed on how to solve my problem here.

  Just to help you understand:

  Each element of the recipe is 3 parts (side, ref_des, part_number).  1 single recipe can have several parts (where the part_number), and each of these pieces should be placed on the lower side or top of the Board that is there "side" comes into play.  Same thing with Ref_Des.

  What is going on

  Select statement returns the RECIPE of ORDER NUMBER A.  There will be multiple records returned by this query.

  Select the Return statement:

  • Side
  • Ref_Des
  • Part_Number

  Example of return:

  B c17 75145-2

  T f14 89242-8

  B s12 45123-3

  etc,

  In general - what I need to do:

  There is a table called AUTO_RECIPE_DETAILS.  I take all of the records returned by the select query above and compare for each record in this table relating to the recipe 30319-000001.  30319-000001 a number of records.  It is the primary key for a whole recipe as seen above.  This primary key is bound the number of data records in this table.  The comparison is to see if all records under RECIPE_NAME 30319 -000001 match all the records returned by the select statement.

  IF IT DOES NOT MATCH: recover the following recipe in this table below 30319 -000002 and make the same comparison.
  

  Here's a perfect example of what the table looks like: (AUTO_RECIPE_DETAILS)

  
  

  RECIPE_NAME SIDE REF_DES PART_NUM

  -30319-000001 C16 87595-1 B

  -30319-000002           T B14 74150-4

  -30319-000001 T B14 34251-2          

  -30319-000001            T F24 84180-7

  -30319-000002 T B12 13710-8          

  
  

  
  

  It is the solution to my original question.  By this thread, it's the right answer and I hope this helps someone who is trying to compare two arrays element-by-element.  In the end, the advice given in this thread were correct and I will be using all of your suggestions and the scrapping of this.  Thank you everyone for your help though.

  FOR index_p IN pid_recipe. FIRST... pid_recipe. LAST

  LOOP

  Result WHEN the OUTPUT = 1;

  FOR index_d IN details_recipe. FIRST... details_recipe. LAST

  LOOP

  IF (pid_recipe (index_p). SIDE = details_recipe (index_d). SIDE)

  AND (pid_recipe (index_p). REF_DES = details_recipe (index_d). REF_DES)

  AND (pid_recipe (index_p). PART_NUM = details_recipe (index_d). PART_NUM)

  THEN

  EXIT;

  ON THE OTHER

  DBMS_OUTPUT. Put_line("IT WAS NOT a MATCH");

  result: = 1;

  EXIT;

  END IF;

  END LOOP;

  END LOOP;

  DBMS_OUTPUT. Put_line('LOOP OUT');

• generate a numerical value to use as the primary key

  Can someone correct me, in an interview that the question was asked.

  How not one generates a numeric value to use as the primary key?

  Years

  We can get it using the sequence. For example:

  CREATE SEQUENCE cust_seq

  START BY
  1000

  INCREMENT OF
  1

  NOCACHE

  NOCYCLE;

  Hi Shu,

  sequence would be my choice and 12 c new type called identity.

• How to fill out the table foreign key to the primary key form

  Hi all

  I'm stuck in this problem for 3 days, and I'm about to research and implement solutions on the internet.

  I have two tables

  create table prim (a number primary key, b varchar2 (100));

  create table CHILD (a number references (a) prim, varchar2 (100)) c;

  I created a page for PRIM table.

  = page name form on PRIM2

  I have manually two columns for the CHILD table to know

  P26_A_1 (for the primary key in the CHILD table)

  P26_C (for the column in the CHILD Table c)

  now when the user clicks on the button CREATE, a row must be inserted into the child table.

  I want to assign the P26_A to P26_A_1 during the validation process, so that a line must be inserted into the PRIM table as well as in the CHILD table.

  How to do this?

  I downloaded my application page in https://apex.oracle.com

  my workspace identifiers are inferior to

  name of the workspace = IMBERT

  username = demo

  password = demo

  kindly guide me.

  Thank you.

  Hello

  I created a new page (page 30) similar to your page and added the insertion of the child. It just check the page and code. It works now, when you insert the prim file is triggered a second trial which inserts the child record manually.

  On page 26 it was some sort of mistake, was easier to create a new as it was almost a standard form.

  Concerning

  Bottom