issue of the index

Spfile/init.ora file parameter exists to force the CBO to do the path of execution of a given statement, use an index, even if the index scan may seem to be calculated in the form of more expensive?

883532 wrote:
Spfile/init.ora file parameter exists to force the CBO to do the path of execution of a given statement, use an index, even if the index scan may seem to be calculated in the form of more expensive?

It's not a good idea to change any parameter to force using the index, because changing the system can degrade the performance of the entire base.
So you should stick to as much as possible the default values.

However if you want your session with force scan restricted index to table scan the following parameter can be set to make cheap scan index. First parameter i.e. optimizer_index_cost_adj is considered when cacculating table scan vs. index scan and to lower the value would increase the cost of the limited index scan.

OPTIMIZER_INDEX_COST_ADJ (set it low, that is to say less than the 100)
optimizer_mode (all is first_rows)
optimizer_index_caching (increase from 0 to 100)
db_file_multiblock_read_count (decrease of current value)
Use as Index indicator / * + index (table_name, index) * /.
Please note that these setting should never tested on at the level of the system otherwise, there may be a performance impact.

Tags: Database

Similar Questions

  • FlowFieldManager focused on the issue of the index

    I have a FlowField Manager where I added an optimization of resources that contains n labelfield bitmapfield. Now I add 5 vfms in ffm using the loop. I put touchEvent on the optimization of resources. I want that if you click on the 5th vfm, touchEvent must run one thing and vfm rest 4 clicks, click features must be the same. So I tried to get the index targeted when I click

    gridVw.getFieldWithFocusIndex()
    

    The problem I faced is that if I click on the optimization of the 5th resources first, I get a value of 5, but then if I click on any other vfms, I get 5 only instead of recovering the respective index. Help, please

    Hey the error was on my side of the management of the touchEvents, I fixed it though

  • Delete the Index of default layout of sensitive HTML5

    Hello

    Is it possible to remove the default layout for HTML5 sensitive Index-icon? (See highlighted box in the picture)

    RoboHelp.png

    When I create the output sensitive HTML5 it four icons are created by default (table of contents, index, glossary and search function). As I did not need an index for my project icon index could confuse users, so I would remove it. I couldn't find all the settings in the output settings to remove.

    Thank you very much for your help!

    Hello

    The answer is Yes!

    However, it will be easy depends on your version of RoboHelp. I hope that you are using version 2015. In this version, you open the pod of Outputs (SSL) and double-click the sensitive layout. Then in the general section on the left side, click on the button customize the selected layout.

    In the left base settings section, click the drop-down on the issue of the Index, and then change true to False.

    If your version of RoboHelp is 11, you probably need to muck about with manually edit files.

    See you soon... Rick

  • synchronization on the issue of re-indexing of validation

    I have an index of text defined as:
       CREATE INDEX CCC_OFFERINGS_TEXT_INDEX ON ccc_offerings ("INDEX_COL")
       INDEXTYPE IS "CTXSYS"."CONTEXT" PARAMETERS ('lexer new_ccc_offerings_lexer datastore 
    new_ccc_offerings_store sync (on commit)');
    /
    If I want to update a row and update the index as well, should I change index_col to trigger the reindexing? Or change any value in the field in sufficient line?

    Thank you
    Doug

    You will need to change index_col and agrees to cause the synchronization of the index. The index is synchronized only when the index is created on the column is changed.

  • The Indexing Service does not not on Windows server R2 (Server Manager)

    In Windows 7 Enterprise or Windows 8

    I activated the indexing service in or out of the Windows features screen.

    After installed I restart the server. Opens the computer management on the server. Indexing Service installed appears under the Services and Applications

    In Windows Server R2 2012, I turned the "Windows Search Service".

    In the computer management screen, showing not the indexing service. ?

    Please help me on this.

    If I had no bad thing help me.

    Thanks :)

    This issue is beyond the scope of this site (for consumers) and to be sure, you get the best (and fastest) reply, we have to ask either on Technet (for IT Pro) or MSDN (for developers)
  • How to check if the indexer works?

    The problem I have is that it generates a lot of disk activity.  If I do works that are heavy on the use of the disc, it becomes almost impossible to work.

    Is it possible to control when the indexer runs in the background?  I can work in two ways.

    1. If a process of a given name is in CPU, run no indexer

    2 in some window of time, don't throw an indexer (indexer or limited only to run in a window of time)

    Thank you

    Hello

    Thank you for your response.

    You can always return to your default configuration by disabling the additional folder that you added to the indexed location (-> Panel-> option change indexing) and rebuild the index (Control Panel-> option-> Advanced Indexing - > rebuild). Indexing of the entire system can lead to search huge index of data which may result from eating up your hard drive space and slow down your system.

    If the issue still persists I would say you are referring to the link below:

    See Mike Hall responded on 15 March 2012
    http://answers.Microsoft.com/en-us/Windows/Forum/Windows_7-files/does-Windows-search-indexing-really-slow-down-PC/1bd40e28-a1ef-486b-9246-867200139b81

    Hope this information helps and if you have other questions related to Windows do not hesitate to post on Microsoft Community, we will be happy to help you.

  • The index is not used

    DB worm 11.2.03

    We have rebuillt a large table (229,952,143 lines) from a backup in our dev, test environments and living, then the table is about the same in all three. Same structure, indexes and data compression.

    However on the issue of the same query in all three envs, in that the index is ignored direct when used in dev and test.

    We have compared the structure of the table and the content using Toad and can see no difference.

    What do we lack?


    Have you checked the statistics on tables and indexes?

  • get the index of the same values in table

    Hi guys,.

    I'm trying to get the index of array elements with the same value but it can solve mine.

    my case is:


    array1 = [1,2,3,4]; <-here are the names of the pages, always in the order of CSA (these table I used only to check the results of my work, probably will not be for you but maybe...)

    array2 = [1,1,2,2,2,3,4,4,4]; <-these numbers are random, but always in the CSA order (these are the names of pages for items in table 3)

    array3 = [a, b, g, i, f, e, c, h, d]; <-these are all the values of the elements I want to work with later. number of articles is still the same as in array2, their indexes are corresponding.

    array4 = [];

    I need to remove array3 everything, but one of each issue of array2 (as I will remove duplicates) or push to array4 an article of array3 for each number of the array array2 (as I'm going to ignore duplicates)

    don't know is my desc is clear enough, but the result I get is:

    ex. [a, g, e, c]

    above example for each number of array2 array3 items, but do not have to be first, can be second or third if etc exist, but have to be alone.

    I thought that if I get duplicate values, the index in the array array2 and delete this index in array3 will get what I want, but can not solve.

    You will appreciate all help.

    Thank you

    Try something like this:

    var array2 = [1,1,2,2,2,3,4,4,4];
    var array3 = ["a","b","g","i","f","e","c","h","d"];
    
    var tempArray = [];
    var resultArray = [];
    var n , x ;
    
    for(var n=array2.length-1;n>=0;n--)
    {
        var string = ""+array2[n];
        tempArray[string] = array3[n];
    }
    
    for(x in tempArray)
    {
        resultArray.push(tempArray[x]);
    }
    
    resultArray.reverse();
    // a,g,e,c
    

    Hope, that helps.

    Uwe

  • scan of the index systematic range

    Hello

    I read about the differences between the systematic index scan range, single scan, skip scan.

    According to the docs, to how the CBO Evaluates in-list of iterators, http://docs.oracle.com/cd/B10500_01/server.920/a96533/opt_ops.htm

    , I can see that

    "The IN -list iterator is used when a query contains a IN clause with values." The execution plan is the same which would result for a statement of equality clause instead of IN with the exception of an extra step. This step occurs when the IN -list iterator feeds section of equality with the unique values of the IN -list. »

    Of course, the doc is Oracle9i Database. (I do not find it in the docs of 11 g)

    And the example 2-1 list iterators initial statement, shows that is used in the INDEX RANGE SCAN.


    On my Oracle 11 GR 2 database, if I issue a statement similar to the example of the doc, so: select * from employees where employee_id in (7076, 7009, 7902), I see that it uses a SINGLE SCAN


    On Oracle Performance Tuning: the Index access methods: Oracle Tuning Tip #11: Unique Index Scan , I read that

    If Oracle should follow the Index Unique Scan, and then in SQL, equality operator (=) must be used. If any operator is used in other than op_Equality, then Oracle cannot impose this Unique Index Scan.

    (and I think this sentence is somewhere in the docs also).

    Thus, when using predicates in the list, why in my case Oracle used the unique scan on primary key column index? Because it wasn't a level playing field.

    Thank you.

    It is Internet... find us a lot of information a lot but don't know who to trust.

    Exactly! It is thought, you should ALWAYS have in the back of your mind when you visit ANY site (no matter the author), read a book or document, listen to no matter WHAT presentation or read responses from forum (that's me included).

    All sources of information can and will be errors, omissions and inaccuracies. An example which is used to illustrate a point can involve/suggest that it applies to the related points as well. It's just not possible to cover everything.

    Your post doc 9i is a good example. The earliest records (even 7.3 always available online docs) often have a LOT of better explanations and examples of basic concepts. One of the reasons is that there were not nearly that many advanced concepts that explaining necessary; they did not exist.

    michaelrozar17 just posted a link to a 12 c doc to refute my statement that the article you used was bad. No problem. Maybe this doc has been published because of these lines:

    The database performs a unique sweep when the following conditions apply:

    • A query predicate refers to all columns in a unique index using an equality operator key, such as WHERE prod_id=10 .
    • A SQL statement contains a predicate of equality on a column referenced in an index created with the CREATE UNIQUE INDEX statement.

    The authors mean that a single scan is ONLY performed for these conditions? We do not know. There could be several reasons that an INLIST ITERATOR has not been included in this list:

    1. a LIST is NOT for this use case (what michaelrozar might suggest)

    2. the authors were not aware that the CBO may also consider a unique analysis for a predicate INLIST

    3. the authors WERE aware but forgot to include INLIST in the document

    4. the authors were simply provide the conditions most common where a single sweep would be considered

    We have no way of knowing what was the real reason. This does not mean that the document is not reliable.

    In the other topic, I posted on the analysis of hard steps, site of BURLESON, and Jonathan contradicted me. If neither Burleson isn't reliable, do not know which author have sufficient credibility... of course, the two Burleson and Jonathan can say anything, it's true I can say anything, of course.

    If site X is false, site is fake, Z site is fake... all people should read the documentation only and not other sites?

    This is the BEST statement of reality to find the info I've seen displayed.

    No matter who is the author, and what credibility that they could rely on the spent items you should ALWAYS keep these statements you comes to mind.

    This means you need to do ' trust and verify. " You of 'trust', and then you "checked" and now have a conflict between WORDS and REALITY.

    On those which is correct. If your reality is correct, the documentation is wrong. Ok. If your reality is wrong, then you know why.

    Except that nobody has posted ANY REALITY that shows that your reality is wrong. IMHO, the reason for this is because the CBO probably MUCH, done a LOT of things that are not documented and that are never explored because there is never no reason to spend time exploring other than of curiosity.

    You have not presented ANY reason to think that you are really concerned that a single scan is used.

    Back to your original question:

    Thus, when using predicates in the list, why in my case Oracle used the unique scan on primary key column index? Because it wasn't a level playing field.

    1. why not use a single sweep?

    2. what you want Oracle to use instead? A full table scan? A scan of the index systematic range? An index skip scan? A Full Scan index? An analysis of index full?

    A full table scan?  For three key values? When there is a unique index? I hope not.

    A scan of the index systematic range? Look a the doc 12 c provided for those other types of indexes

    How the Index range scans work

    In general, the process is as follows:

    1. Read the root block.
    2. Read the bundle branch block.
    3. Replacing the following steps until all data is retrieved:
      1. Read a block of sheets to get a rowid.

      2. Read a block to retrieve a table row.

    . . .
    For example, to analyze the index, the database moves backward or forward through the pads of sheets. For example, an analysis of identifications between 20 and 40 locates the first sheet block that has the lowest value of key that is 20 or more. The analysis produced horizontally through the linked list nodes until it finds a value greater than 40 and then stops.

    If that '20' was the FIRST index value and the '40' was the LAST one who reads ALL of the terminal nodes. That doesn't look good for me.

    How to index full scans of work

    The database reads the root block and then sailed on the side of the index (right or left hand if do a descending full scan) until it reaches a block of sheets. The database then reads down the index, one block at a time, in a sorted order. The analysis uses single e/s rather than I/O diluvium.

    Which is about as the last example is not?

    How to index Fast Full Scans work

    The database uses diluvium I/O to read the root block and all the blocks of leaf and branch. Databases don't know branch blocks and the root and reads the index on blocks of leaves entries.

    Seems not much better than the last one for your use case.

    Skip index scans

    An index skip scan occurs when the first column of a composite index is "skipped" or not specified in the query.

    . . .

    How Index Skip scan work

    An index skip scan logically divides a composite index in smaller subindex. The number of distinct values in the main columns of the index determines the number of logical subindex. The more the number, the less logical subindex, the optimizer should create, and becomes the most effective analysis. The scan reads each logical index separately and "jumps" index blocks that do not meet the condition of filter on the column no leader.

    Which does not apply to your use cases; you do not have a composite index, and there is nothing to jump. If Oracle were to 'jump' between the values of the list in it would be still reads these blocks 'inbetween' and them to jump.

    Which brings back us to the using a single scan, one at a time, for each of the values in the list in. The root index block will be in the cache after the first value lies, so it only needs to be read once. After that just Oracle detects that the entry of only ONE necessary index. Sounds better than any other variants for me if you are only dealing with a small number of values in the IN clause.

  • 2015 RoboHelp. Main project generated does not recognize subcategories in the keywords in the index.

    I have a master project containing external links to many projects (more than 70) and all the index entries are combined to create a master index for the help system. After I upgraded to RH2015 and I generated the subproject both main project, keyword/subkeyword relationships disappeared. Entry index keywords are listed without any subcatgories although the project has them. Like this:

    So now I have a giant list of keywords without the indentations to delimit groups of keywords. I did a large part of the index by hand using the properties of the section and the format "keyword\subkeyword". This delimiter has changed? Anyone know or have the same problem? Am I missing a value somewhere?

    I was by the who is new and Forums here, but don't see anything.

    Thanks in advance.

    Hello

    I tried it with the latest patch applied RoboHelp and it works very well at my end.

    Index the thin air in the WebHelp output.

    We have fixed this bug in the latest version of patch. Please make sure that you have updated the HR. Latest version after you apply the hotfix would be 12.0.1.338

    For the application of the hotfix, see help > updates and apply the available update.

    If after application of the patch also, you face this issue please post here.

    Thank you
    Manu of FIFA

  • Display performance of resources by using the index of area XDBHI_IDX

    Hi all

    We have an application XMLDB home grown to make the validation of diagram against incoming messages. Enforcement issues several queries like below. I know, it analyzes the hard, which is very bad, but it's not where the real problem is at the moment. The problem is with the index of XDBHI_IDX field against xdb resource table $. We use a very specific way of results in the rows returned 0 or 1, but as you can see that the domain index has an intermediate result of 48041 lines, so the index is not effective here. Statistics are up to date, the index has been rebuild. Does anyone know what we can do with the index of the field to do what he must do: identify an xml document in this way?
    SELECT 0 
    FROM
     resource_view WHERE any_path=
      '/home/app/incoming/ARCH_IN/2012/01/592174'
    
    
    call     count       cpu    elapsed       disk      query    current        rows
    ------- ------  -------- ---------- ---------- ---------- ----------  ----------
    Parse        2      0.02       0.02          0       1041          0           0
    Execute      2      0.00       0.00          0          0          0           0
    Fetch        2     81.26      85.43          0     202556     576158           0
    ------- ------  -------- ---------- ---------- ---------- ----------  ----------
    total        6     81.28      85.45          0     203597     576158           0
    
    Misses in library cache during parse: 1
    Optimizer mode: ALL_ROWS
    Parsing user id: 67  (app)   (recursive depth: 3)
    
    Rows     Row Source Operation
    -------  ---------------------------------------------------
          0  TABLE ACCESS BY INDEX ROWID XDB$RESOURCE (cr=341531 pr=0 pw=0 time=60883725 us)
      48041   DOMAIN INDEX  XDBHI_IDX (cr=311030 pr=0 pw=0 time=1548774 us)
    Kind regards
    Rob.

    PS: The database version is 10.2.0.3.0

    Hi Rob,

    See EQUALS_PATH (and UNDER_PATH) conditions: http://docs.oracle.com/cd/B19306_01/server.102/b14200/conditions010.htm#i1051094

    SQL> select *
      2  from resource_view v
      3  where equals_path(v.res, '/office/excel/docs') = 1
      4  ;
    
    Execution Plan
    ----------------------------------------------------------
    Plan hash value: 3007404872
    
    --------------------------------------------------------------------------------------------
    | Id  | Operation                   | Name         | Rows  | Bytes | Cost (%CPU)| Time     |
    --------------------------------------------------------------------------------------------
    |   0 | SELECT STATEMENT            |              |    81 | 17172 |    32   (0)| 00:00:01 |
    |   1 |  TABLE ACCESS BY INDEX ROWID| XDB$RESOURCE |    81 | 17172 |    32   (0)| 00:00:01 |
    |*  2 |   DOMAIN INDEX              | XDBHI_IDX    |       |       |            |          |
    --------------------------------------------------------------------------------------------
    
    Predicate Information (identified by operation id):
    ---------------------------------------------------
    
       2 - access("XDB"."EQUALS_PATH"(SYS_MAKEXML('8758D485E6004793E034080020B242C6',734
                  ,"XMLEXTRA","XMLDATA"),'/office/excel/docs',8888)=1)
    
  • Name of the PK, unique constraints and to support the index

    I want to have my primary key constraint and index support share of the same name, IE:
    CREATE UNIQUE INDEX MYTABLE_PK ON MYTABLE(...);
    ALTER TABLE MYTABLE ADD CONSTRAINT MYTABLE_PK PRIMARY KEY(...);
    Without definition explicit a unique index using the relational model, the generated DDL added 'X' for the name of the index:
    CREATE UNIQUE INDEX MYTABLE_PKX ON MYTABLE(...);
    ALTER TABLE MYTABLE ADD CONSTRAINT MYTABLE_PK PRIMARY KEY(...);
    I tried to add an index unique explicit to the table, but he changed the name (adds "v1") when I leave the table editor:
    CREATE UNIQUE INDEX MYTABLE_PKv1 ON MYTABLE(...);
    ALTER TABLE MYTABLE ADD CONSTRAINT MYTABLE_PK PRIMARY KEY(...);
    I have the same problem with index & unique constraints.

    Issues related to the:
    Can I generate DDL with name matching? "v1" thing seems unlikely, he doesn't want not myself save the definition as I want.
    Where are the transformations of naming for this location? I found tools, preferences, and Data Modeling/naming Standards/Templates but this nugget does nto seem to be there.

    Thank you.

    Hi Mike,.

    The Production data release model 3.1 has been updated to allow constraints unique and primary and their indexes share the same name.

    David

  • Which switch to index for the index bitmap in Oracle Standard Edition

    Hello

    I have to move from Oracle Enterprise edition to standard edition (oracle11g). As standard edition does not support bitmap indexes. But the current database which is an Enterprise edition a bitmap index a column-based date or varchar2 or column in a table. The tables have approximately 60000000 records. I would like to know what index go for bitmap index.


    Kind regards
    Vaibhav

    Published by: Vaibhav on November 7, 2011 05:35

    The BTree index certainly can and are frequently used when values are not unique (e.g. are duplicated).

    uniqueness isn't the issue. The relative number of distinct values (relative to the total number of lines) is important. An advantage of BitMap index BTree indexes, it's that BTree indexes can be composite - made up of multiple columns.

    You can read the documentation on the index.

    http://download.Oracle.com/docs/CD/E11882_01/server.112/e25789/indexiot.htm#CBBECABB

    http://download.Oracle.com/docs/CD/E11882_01/server.112/e25494/indexes.htm#i1007132

    Hemant K Collette

  • The index of the frame out of range

    I use Lynda SG training and becomes the first 01_01_interface example Frame index out of range. Files in Adobe Bridge are .mov and a rate of 23.976 which is what I put in the reading and editing-> Base frame rate in SG. I can load the files in first and they play normally in the timeline panel.

    Thanks to Robbie Carman for his great support on this issue. The resolution is to remove and reinstall SpeedGrade. I know, big hammer approach, but I didn't want to be down until the developers could watch and hopfully they know what triggers this error in their code and will come with a fix in a future update or release. It would be great to hear from Adobe if there is a more simple solution and a lot less time.

  • INDD 6.0.6 give up when I try to delete the reference in the index

    See also http://forums.Adobe.com/message/4263687 for a discussion of the same problem. Ask here, I'm starting a discussion separate from the same issue affecting someone else (me).

    I am running INDD 6.0.6 on OS X 10.6.8 on a MacBook Pro (2.53 GHz Intel Core 2 Duo). I have a document. INDD that is part of a 50-page book. The document includes an index. The index was imported originally from MS Word (from another user, unknown version). I'm rewriting the index, editing and re-release strongly. I recently discovered that the index is a reference without a target. To be clear, I don't know of a reference in the text of the document. It is an index entry, created by new cross-reference... menu item in the Index pane. There is no target, because when you look at it with forwarding options, there is a first-level topic, but the referenced field (below the Type see also) is empty.

    I can't delete this entry. When I try to delete, INDD crashes. When INDD covers, he warns that the document is may be damaged, and if I try to delete it again, INDD breaks down. If I try to change the referenced field, INDD accepts but does not take into account the change (the closing of the shutter, but the remains of the unchanged index).

    My current solution is to change the theme to ZZZ and add a new index entry (ZZZ: corrupt entry: delete this before shipping), but it is less satisfactory. What can I do to remove the corrupted index cross-reference?

    The biggest problem is that even if you and someone from Adobe to be able to actually understand what that is the problem and that it is, in fact, a bug, there's nothing they can do to help you. There won't be any several bug fixes for CS4. My memory is that he had some bugs in indexing in the first version of CS4 and at least some of them are fixed, then you must install the patch...

Maybe you are looking for

  • How is it my extensions keep endangered?

    I install my extensions. They are always installed because I see some of them below the toolbar. But when I go to tools-> Modules-> Extensions it says I have one installed. Now if I go to the profiles folder and delete all files with the word "extens

  • How to use a PowerMac G4 monitor with another computer or pc?

    Hi, I have an old PowerMac G4 I use ever more because they have to slow down. But I wouldn't throw because he has such a nice monitor. So I was wondering is it possible to use the G4 PowerMac with other calculates such as a PC. I know that this monit

  • HP laptop laptop 15-ac198TU: is my normal hard drive?

    I just bought my laptop and heard this noise of crackling, as similar to the video of my hard drive. Is this normal? Or is my drive defective? https://www.YouTube.com/watch?v=hBcFLZ2S7Fk

  • XOOM FE: Why is not all 16 GB available storage?

    Just to start my FE Xoom. It is supposed to have 16 gig storage, but it shows only about 12 available gig. Why?

  • How to msconfig

    I am running Windows 7 and I can't understand how get you to msconfig.  Any ideas?