Delete Performance index organized Tables

Similar Questions

• Partitioning or an index organized table. Suggestion required.

  Hi gurus,

  We decided to perfomance increase in customer table that has more than 100 million records

  {code}

  customer_id number,

  cust_name varchar,

  Date of Applied_date,

  City varchar (100)

  {code}

  This is the structure of the customer table.

  We decided to composite partition the table based on date (range) applied and customer_id (hash).

  I am confused to go with table index (where tables and indexes are stored together) for better performance.

  Please suggest what we I'm going?  for best performance.

  Please answer

  Supersen

  If the query predicate (WHERE clause) include the Partition key column, Oracle can make the size of Partition - that is to say identify the target Partition.  Otherwise, he would have to do a full Table Scan because he doesn't know what Partition the target Row (s) is in.

  For example, if you are partitioning by APPLIED_DATE but your request is on the table by CITY, Oracle cannot identify the target Partition and do a Scan of Table full - even if you subpartition by CUSTOMER_ID and integrate CUSTOMER_ID in your query, Oracle cannot identify the Subpartition because it cannot identify the Partition.

  Hemant K Collette

• Index organized Tables

  What is logical rowid in IOT? are they kept physically somwhere like physical rowId
  
  What are secondary indexes?
  
  what he meant by leaves block splits? When and how it happens?
  
  and the primary key for a table in index constraint cannot be abandoned, delayed or off, is this true, if yes then Y
  
  How overflow works? how the two clauses are implemented PCTTHRESHOLD and INCLUDING.how they work?
  
  Published by: Juhi on October 22, 2008 13:09

  I'm sort of tempted to simply point you in the direction of the official documentation (concepts guide would be a start. See http://download.oracle.com/docs/cd/B28359_01/server.111/b28318/schema.htm#sthref759)

  But I would say one or two other things.

  First, physical ROWID not is not physically stored. I don't know why you would think they were. Certainly the ROWID data type can store a rowid if you choose to do, but if you do something like "select rowid from scott.emp", for example, you will see the ROWID that are generated on the fly. ROWID is a pseudo-column, not physically stored anywhere, but calculated each time as needed.

  The difference between a physical rowid and logic used with IOT boils down to a bit of relational database theory. It is a rule in melting of relational databases that a line, once inserted into a table, must never move. In other words, the identifier that is assigned at the time of his first insertion, must be the rowid he "keeps" for ever and ever. If you ever want to change the assigned lines in an ordinary table ROWID, you must export them, truncate the table, and then reinsert them: Insert charges, fees rowid. (Oracle bend this rule for various purposes of maintenance and management, according to which 'allow the movement of line"allows lines without a table, but the general case is still valid for most).

  This rule is obviously hopeless for the index structures. It was true, an index entry for "Bob" which is updated to "Robert" would find next to the entries for 'Adam' and 'Charlie', even though she now has a value of 'R '. Effectively, 'line' a 'b' in an index must be allowed to "move" a sort of 'r' of the block if it's the kind of update that takes place. (In practice, an update to an index entry consists of performing a delete followed by a re - insert, but the physicalities do not change the principle: 'lines' in an index must be allowed to move if their value is changed; rows of a table do not move, no matter what happens to their values)

  An IOT is, at the end of the day, simply an index with columns much more in it that a 'normal' index would - he, too, has thus allow its entires (his 'rows', if you like) to move. Therefore, an IOT cannot use a standard ROWID, which is assigned only once and forever. Instead, one must use something that takes into account that its lines may wander. It's the logical rowid. It is not more 'physical' as a physical rowid - or are physically stored anywhere. But a 'physical' rowid is invariable; a logic is not. Logic, it is actually built in part of the primary key of the ITO - and this is the main reason why you can never get rid of the primary key on the IOT constraint. Be allowed to do would be to you to destroy an organizing principle for its content which has an IOT.

  (See the section called "The virtual ROWID" and continued on this page: http://download.oracle.com/docs/cd/B28359_01/server.111/b28318/datatype.htm#CNCPT1845)

  IOT so their data stored inside in the primary key order. But they only contain the primary key, but all the other columns in the definition of 'table' too. Therefore, just as with an ordinary table, you might sometimes find data on columns that are NOT part of the first key - and in this case, you might well these columns non-primary keys are indexed. Therefore, you create ordinary index on those columns - at this point, you create an index in an index, really, but it's a secondary question, too! These additional indices are called 'secondary index', simply because they are "subsidiary clues" in the main proceedings, which is the 'picture' himself laid out in the primary key order.

  Finally, a split block of sheets is simply what happens when you have to make room for the new data in an index block which is already filled to overflowing with the existing data. Imagine an index block may not contain four entries, for example. Fill you with entries for Adam, Bob, Charlie, David. Now, you insert a new record of 'Brian '. If it's a table, you can take Brian to a new block you like: data from a table have no positional sense. But the entries of an index MUST have positional significance: you can't just throw MC Bean and Brian in the middle of a lot of Roberts, bristling. Brian DOIT pass between the existing entries for Bob and Charlie. Still you can not just put him in the middle of these two, because then you'd have five entries in a block, not four, which we imagined for the moment to be maximally allowed. So what to do? What you do is: get an empty block. Move Charlie and David entries in the new block. Now you have two blocks: Adam-Bob and Charlie David. Each has only two entries, so each has two 'spaces' to accept new entries. Now you have room to add in the entry for Brian... and if you end up with Adam-Bob-Brian and Charlie David.

  The process of moving the index entries in a single block in a new one so that there is room to allow new entries to be inserted in the middle of existing ones is called a split of block. They occur for other reasons too, so it's just a brilliant of them treatment, but they give you the basic idea. It's because of splits of block that indexes (and thus IOT) see their 'lines' move: Charlie and David started in a single block and ended up in a completely different block due to a new (and completely foreign to them) Insert.

  Very well, infinity is simply a means of segregation of data in a separate table segment that would not reasonably be stored in the main segment of the ITO himself. Suppose that you are creating an IOT containing four columns: one, a digital sequence number; two, a varchar2 (10); three, a varchar2 (15); and four, a BLOB. Column 1 is the primary key.

  The first three columns are small and relatively compact. The fourth column is a blob of data type - so it could be stored whole, multi-gigabyte-size monsters DVD movies. Do you really want your index segment (because that's what an IOT really is) to ball to the huge dimensions, every time that you add a new line? Probably not. You probably want 1 to 3 columns, stored in the IOT, but column 4 can be struck off the coast to a segment on its own (the overflow segment, actually) and a link (in fact, a physical rowid pointer) can bind to the other. Left to himself, an IOT will cut each column after the a primary key when a record that threatens to consume more than 50% of a block is inserted. However, to keep the main IOT small and compact and yet still contain data of non-primary key, you can change these default settings. INCLUDE, for example, to specify what last non-primary key column should be the point where a record is split between "keep in IOT" and "out to overflow segment." You could say "INCLUDE COL3" in the previous example, so that COL1, COL2 and COL3 remain in the IOT and only COL4 overflows. And PCTTHRESHOLD can be set at, say, 5 or 10 so that you try to assure an IOT block always contains 10 to 20 saves - instead of the 2 you would end up with default if 50% of kicks.

• Why slow DML in Index organized tables

  I learned that ITO system was not suitable for tables that have a high volume of DML operations.
  
  I want to know that:
  
  1.) why DML operations are slow when we have data and indexes in the same place for ITO?
  2.) why we take extra precautions for fragmentation to ITO that pile of paintings organized?

  It's as long as your application does not change for the PK values that inspire you the IOT.

  If you have an application that actually modifies the values of primary key - Ouch!

  Here's how to think this through:
  Think of an Index on a column usually.
  What happens when you update the value of this column for a line or set of lines?
  The update to the line goes into the table block (and if the line does not expand or PCTFREE is adequate, there is no chaining line)
  However, the update of the index entry is not just an update. Because an Index is a Structure y (unlike a heap table), in order to change the value of an Index key (even when not unique), you have to 'remove' of the 'location' (IE block) he currently resides to and "insert" in the new "place" (block) corresponding to the new value. So, for example, if change 'Aman' (probably at the head of the Index tree) to "Hemant" (somewhere in the middle), you will find that "Hemant" belongs to another block - so that the index of "Aman" entry should be removed and a new entry for "Hemant" (pointing to the same ROWID) inserted in the correct index leaf block where 'Hemant' belongs.

  Now, instead of an Index on a single column, think an whole table-ITO is an ordered structure. If you change the value of the key to the order (ie the Index key) then the line should be moved to the correct location that he must belong.

  As it is, it is very bad design to change the values for the PK building. an IOT in such a severely design adds to the problem. Now, instead of simply delete and insert for the column values, the entire row should be deleted and inserted.

  However, if you do not change the values of the PK, then you should not have problems with updates. However, if the size of the line is large (or increases with updates), you will need to handle the overflow.

  Hemant K Collette
  http://hemantoracledba.blogspot.com

• Somehow, I deleted my index.dat in the Cookies folder.

  Somehow, I deleted my index.dat in the Cookies folder.  How do I get it back and I really need?

  Hello

  • What was the location of the folder where you deleted it go?
  The index.dat file is a database file. This is a repository of information such as web URLS, search queries, and files recently opened. Its purpose is to allow quick access to the data used by Internet Explorer. For example, all visited web addresses are stored in the index.dat file, which allows to find quickly the AutoComplete match as long as the user types an Internet Explorer web address. The index.dat file is specific to the user and is open as long as a user is connected Windows. Separate index.dat files exist for the history, cache and cookies in Internet Explorer.
  The index.dat file is never resized or deleted. A large index.dat file can affect the performance.
   
  Note: The .dat extension is commonly used for data files (files that are not readable by humans and not to hold a binary based on documents). It is possible to find named "index.dat" files that are not used by Internet Explorer.

• Insert / * + parallel * / performance index

  Insert / * + parallel * / performance index

  Hello

  I performed the procedure below

  CREATE OR REPLACE PROCEDURE bulk_collect

  IS

  SID TYPE TABLE IS NUMBER;

  Screated_date TYPE IS an ARRAY OF DATE;

  Slookup_id TYPE TABLE IS NUMBER;

  Surlabasedesdonneesdufabricantduballast ARRAY TYPE IS VARCHAR2 (50);

  l_sid sid;

  l_screated_date screated_date;

  l_slookup_id slookup_id;

  l_sdata surlabasedesdonneesdufabricantduballast;

  l_start NUMBER;

  BEGIN

  l_start: = DBMS_UTILITY.get_time;

  SELECT id, created_date, lookup_id, data

  BULK COLLECT INTO l_sid, l_screated_date, l_slookup_id, l_sdata

  FROM big_table;

  -dbms_output.put_line (' after collection in bulk: ' | systimestamp);

  FORALL indx IN l_sid. FIRST... l_sid. LAST

  INSERT / * + parallel (big_table2, 2) * / INTO big_table2 values (l_sid (indx), l_screated_date (indx), l_slookup_id (indx), l_sdata (indx));

  -dbms_output.put_line (' after FORALL: ' | systimestamp);

  COMMIT;

  Dbms_output.put_line ('Total elapsed:-' |) (DBMS_UTILITY.get_time - l_start) | "hsecs");

  END;

  /

  DISPLAY ERRORS;

  I want to confirm if the query is running in parallel. I checked the tables below to confirm if the insert statement is run in parallel, but none of them returns all the rows.

  Select * from V$ PX_SESSION where sid = 768

  Select * from V$ PX_SESSTAT

  Select * from V$ PX_PROCESS

  Select * from V$ PX_PROCESS_SYSSTAT

  Select * from V$ PQ_SESSTAT

  Please may I know how to find out the parallel execution of / * + parallel (table_name, 2) * / reference

  Thank you

  I'd go for the SQL insert/selection option as suggested.

  Bulk insert is the APPEND_VALUES of 11r2 trick that will lead to a direct path load. Parallel is to directly load path, but if you are bench marking may include this as an additional test.

• delete the index in the transformation script

  In a custom transformation script, I would delete the indexes on a table.  However, I don't see that there is no table.removeIndex function ().  Is there another way I can drop an index?

  You can use the table.remove(KeyObject key) method, passing the Index into the KeyObject parameter.

  David

• Deleting lines in a table with a button

  Good day all.

  I seemed to have encounter a problem with trying to add a delete button in a table that deletes a row. Let me expain.

  The form contains 1 table that has 7 elements composed of fields of text and drop downs. This table is in its own subform.

  There is a button to add lines that the user needs. The code I use to add lines: psl_list_subform.instanceManager.addInstance (1);

  I was asked to add a delete for a user button can delete rows. I added this at the end of the table. SO whenever a row is repeated, there's a button Delete. The code I am "trying" to use is;

  Table4.Row1.instanceManager.removeInstance (this.parent.index);

  When I click on the button Delete, nothing happens. I grew up the JavaScript debugger, there is no errors.

  Any ideas what I missed.

  Thank you all

  Chomp

  Hello

  my understanding of your form, you can add new instances of the "psl_list_subform" subform that contains a single table row.

  The hierarchy that resemble 'psl_list_subform. Table4.Row1.removeButton ".

  To remove an instance of the subform, a button in the row of the table, the script needs to refer to the 3rd parent of the button Delete.

  this.parent.parent.parent.instanceManager.removeInstance(this.parent.parent.parent.index);
  

  Explanation: this = Radiobutton2, 1 parent = Row1, 2nd parent = table 4, 3rd mother = psl_list_subform

• Recovery of the records by using the Ref Cursor or indexes per Table (which is better)

  Hi all
  
  I am interested to know if there is a performance (or other) advantages to return a result set from an Oracle stored procedure for a client application (for example, in Java) by using a Ref Cursor or Index by Table, respectively. Most of the people I met who know Java seem to use a Ref Cursor but did not say why this method is preferable. I'm not too familiar with Java and do not have the opportunity to test the difference between either method, but I am very interested in the other user forum about this view, gauging
  
  Kind regards
  
  Kevin.

  KevinFitz wrote:
  Hi zerathul,

  Thanks for the quick and helpful response. A REF CURSOR would be the best solution if the same set of results (content and number of records returned) should be dealt with by the application of the 'customer '. I'm guessing that maybe in this situation 'theoretical' that there might be less network traffic to return the set of results through an associative array,

  Kind regards

  Kevin.

  Yes, it would always be the best solution, because an associative array would mean collecting all the data in memory of expensive PGA on the database server before they pass any return on the network, while a fair Ref cursor is to feed the data over the network (maybe a little extra load, but you were unlikely to notice). Also the client application would treat a ref as of rows returned cursor data recovery and could treat them upon their arrival, an associative array is a collection of data which will then be entirely spent before any treatment could be done and then the treatment should go through the entire table to do.

  REF CURSOR will also provide other information such as the error codes etc regarding SQL if necessary. If you get an error when filling a table on the side of the database, it is not so easy to recover this error to the client.

  REF CURSOR is designed for this purpose. Use them.

• Qosmio G50-12 X - Windows 7 performance index decreased

  After having changed the HARD and WIN7 32-bit drive to SSD and Win7 64 bit Windows Experience Index decreased:
  for processor - 6.1 to 3.9
  for memory (RAM) - 5.9-4.5.

  This isn't good, is it?
  Does anyone know what might be a reason?
  Does anyone have the same problem?

  All the official drivers for Win7 64 (chipset, video, etc.), tried to install different versions for other OS-did not help.
  PC: Qosmio G50-12 X (PQG55E).

  You have changed the system to 32 bit to 64 bit.
  There is a difference between 64-bit and 32-bit system and therefore the performance index will also be different.

  To be honest, I don t care about clean internal Windows experience index.
  Firstly this Index isn't very useful because any change in the system may affect the unique results. So the results are not very significant.

  If you want to get more details about Windows 7 performance index, I recommend this MS site:
  http://Windows.Microsoft.com/en-us/Windows7/products/features/Windows-experience-index

  However, the upgrade of the SSD HARD drive is the best decision you could ever made.
  I also changed the HARD drive to SSD drive and the performance gain is huge

• Satellite P200-1FZ: Question about Vista performance index?

  I recently bought a P200D-128 announced as having 256 MB of memory graphic dedicated only to find only has a HD2400 with 128 MB card (the name must have been an idea, I know).

  I was looking for a model with 256 MB I had read that it was recommended for good graphics performance in Vista.
  On the P200-128 model Vista performance index showed:

  Processor: 4.8
  Memory: 5.9
  Graphics: 3.3
  Games graphics: 3.7
  Hard drive: 5.2

  If the overall score of 3.3 seems not be limited by the graphics performance.

  I now plans to upgrade this model to a P200-1FZ (which has a HD2600 with 256 MB memory card), but would like to know if it significantly improves the score of graphics and Vista performance index.

  If anyone has this model (or a relative) and could tell me the VEI score, I would be very grateful.

  Thank you.

  Hello

  Just FYI: I Satellite P200D-111 with ATI Mobility Radeon X 2600 almost 5 months now. I use Vista Home Premium and to be honest, I'm quite satisfied with the performance of Vista. Up to now, I also tested with several games such as Call of Duty 2, Call of Duty 4, El Matador and older games like FarCry and Max Payne 2 WXP. It works perfectly.

  I like Call of Duty 4. He funs all simply fantastic. I do not even use complete running. At the moment I think to upgrade RAM to have better running OS. in the end, I can say one thing: for the reasonable price, I have large notebook.

  Good bye

• Satellite A100 - low Windows Vista performance index

  Hey there,

  I bought a Toshiba Satellite A100 just for more than a year now with Vista Home Premium. I recently formatted the laptop and installed Vista Business. When I got Home Premium, my 'Windows experience index' (found in Control Panel > system) has been a 3.0 for the graphics. Under Business, is however now that 1.0. I guess that it has not detected the graphics hardware on my laptop.

  How do it detects hardware?

  > I guess that it has not detected the graphics hardware on my laptop.

  I put t know what do you say that it has not detected the graphic material, but you should definitely check out if the graphic and other driver drivers Toshiba have been installed on your laptop properly.

  In addition, the Windows Vista experience index can change and can go down if more programs are installed on the system.
  I noticed that my Windows Vista performance index decreases every time if a 3rd party application has been installed and then removed from the system.

  In my opinion, Windows Vista index experience might be less because you have installed a newer version of the Vista operating system which contains functions of Vista more and so would need of more resources.

  Best regards

• How to index a table on multiple sites?

  Hello

  How to index a table on multiple sites?

  I searched this issue and was not able to find the answer. I understand that it can be done with loops, but I don't know how.

  I use the detector of crete vi for frequency domain data collected a VNA (s2p) file. The products contain a table of amplitudes and a table of locations. The problem is that the locations refer to the index of table of amplitude, which is not the same as the frequency. My idea is that I can use this output of the places table to index the frequency to the detected peak frequencies table and then draw these, as well as some analysis data and manipulation on them. Currently, I can do this only by consulting table on the front panel.

  The entrance to the peak detector is currently a table 1 d of the scale (what is the problem?).

  I also looked at the supply frequency & estimate VI, but this VI seems only exit of scalar data for the largest peak, not exactly what I'm looking for.

  Thanks for your help.

  You have a second table for the tested frequency?  If so, then you are right that you just need to index this table with the indexes by the Ridge detector.  Use a loop for.  Automatic index to the index, use index in array to get the value of the frequency and autoindex on frequencies.

  

• What is the physical meaning of automatic indexing of table entry...

  What is the physical interpretation of the automatic indexing. ?

  You wire up a table on the edge of a loop, it sequentially will index the table for you as he travels the loops. A While loop will also do this, but it is much more common on loops For, therefore, loops For making automatically while the While loops must be 'right click' and said to the index in the array. Get it?

• Performance index Windows sides my RAM at 5.5, how can I increase this score.

  I have Windows 7 Home Premium 32 bit, and the performance index scores my RAM to 5.5 (lowest score).  I have 4 GB of RAM installed, which is the maximum 32-bit windows can use.  Because a maxed out what's a low score?

  -Mike

  Because it has to do with the amount of RAM you have, but rather that it's good. What you have in your computer is probably some 800 MHz RAM, which is realitivly slow compared to my 1600 MHz... that is much faster.