Oracle Indexing on Specified Columns

Hi ,
I have read that Oracle Indexing improve performance for Database engines while searching data .
Therotically i know this , but pratically , didn't written any indexes actually .
For example , we have a below index in our Application :
CREATE UNIQUE INDEX M_Index on F_SECTION("FMAT_ID", "SECT_NAME")
PCTFREE 10 INITRANS 2 MAXTRANS 255
STORAGE(INITIAL 16384 NEXT 16384 MINEXTENTS 1 MAXEXTENTS 121
PCTINCREASE 50 FREELISTS 1 FREELIST GROUPS 1 BUFFER_POOL DEFAULT)
TABLESPACE "SYSTEM" ;
I am having query here , This Table F_SECTION is consisting of many columns under it , but anybody please tell me why is it that the Index has been created based on only those columns .
waiting for your ideas , thanks in advance .

Hi ,
I have read that Oracle Indexing improve performance for Database engines while searching data .
Therotically i know this , but pratically , didn't written any indexes actually .
For example , we have a below index in our Application :
CREATE UNIQUE INDEX M_Index on F_SECTION("FMAT_ID", "SECT_NAME")
PCTFREE 10 INITRANS 2 MAXTRANS 255
STORAGE(INITIAL 16384 NEXT 16384 MINEXTENTS 1 MAXEXTENTS 121
PCTINCREASE 50 FREELISTS 1 FREELIST GROUPS 1 BUFFER_POOL DEFAULT)
TABLESPACE "SYSTEM" ;
Hi,
During the database design phase,the database modellers would have made the combination of "FMAT_ID" and "SECT_NAME" as Primary Key which Uniquely identifies the record in your table.
Regards,
Achyut

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Hi,
I need to create an oracle text index on 2 columns.
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DESCRIPTION - CLOB = contains partial HTML data
This is what I created.
begin
ctx_ddl.create_preference ('Title_Description_Pref', 'MULTI_COLUMN_DATASTORE');
ctx_ddl.set_attribute('Title_Description_Pref', 'columns', 'TITLE, DESCRIPTION');
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begin
ctx_ddl.create_preference ('bid_lexer', 'BASIC_LEXER');
ctx_ddl.set_attribute('bid_lexer', 'index_stems', 'ENGLISH');
ctx_ddl.create_section_group('htmgroup', 'HTML_SECTION_GROUP');
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Thanks,
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Hi,
I need to create an oracle text index on 2 columns.
TITLE - varchar(255) = contains plain text data
DESCRIPTION - CLOB = contains partial HTML data
This is what I created.
begin
ctx_ddl.create_preference ('Title_Description_Pref', 'MULTI_COLUMN_DATASTORE');
ctx_ddl.set_attribute('Title_Description_Pref', 'columns', 'TITLE, DESCRIPTION');
end;
begin
ctx_ddl.create_preference ('bid_lexer', 'BASIC_LEXER');
ctx_ddl.set_attribute('bid_lexer', 'index_stems', 'ENGLISH');
ctx_ddl.create_section_group('htmgroup', 'HTML_SECTION_GROUP');
end;
create index Bid_Title_Index on Bid(title) indextype is ctxsys.context parameters ('LEXER bid_lexer sync (every "sysdate+(1/24)")');
create index Bid_Title_Desc_Index on Bid(description) indextype is ctxsys.context parameters ('LEXER bid_lexer DATASTORE Title_Description_Pref sync (every "sysdate+(1/24)") filter ctxsys.null_filter section group htmgroup');
The problem is when I do a CONTAINS(description, '$(auction)')>0. I get results where the descriptions have the "auction" word (which is correct). But, the results also returned rows where the search word is inside an IMG tag. e.g. <img src="http://auction.de/120483" alt="Auction Logo"/>.
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Index on multiple columns issue Oracle 9i

Hi,
I have a couple of issues and would appreciate it if anyone can help:
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Index 2 on FICE_CD, Org_Id and Effdt etc.
I have 9 such indexes and all of them hav Effdt in it.
My question is if I query the table and always use a subquery to get the max Effdt rows form the table, will the above indexes help in my query or will I have to create another index just on Effdt so that my Query runs faster.
b). I have a target table with more than 20 million rows in it. This table has an Effdt too and I would like to find the max effdted row in this table as well so that I can then use that date-time stamp in my ETL tool to do an incremental update from my source table each night. But since the amount of rows is huge, my query runs forever. I have a normal non-unique index on Effdt. Is there another way I can optimize this table? Currenlty I have resorted to getting all rows from source that are >= (sysdate -1), but I would prefer to get the max date-time stamp from the target table itself.
Thanks,
CJ

Hi ,
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E.CLASS_RANK, E.CLASS_SIZE, E.PERCENTILE, E.UM_GPA_EXCLUDE, E.UM_EXT_ORG_GPA, E.CONVERT_GPA,
E.UM_EXT_ORG_CNV_CR, E.UM_EXT_ORG_CNV_GPA, E.UM_EXT_ORG_CNV_QP, E.UM_GPA_OVERRIDE, E.EXT_ACAD_LEVEL,
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H.EFF_STATUS, H.SCHOOL_CODE, H.LS_SCHOOL_TYPE, H.ATP_CD, H.CITY, H.STATE, H.COUNTRY,
H.DESCR "SCHOOL DESCR", H.PROPRIETORSHIP
FROM PS_EXT_ACAD_SUM E, PS_EXT_ACAD_DATA F, PS_EXT_DEGREE G, PS_EXT_ORG_TBL H
WHERE E.EXT_ORG_ID = F.EXT_ORG_ID AND E.EMPLID = F.EMPLID
AND E.EXT_ORG_ID = G.EXT_ORG_ID AND E.EMPLID = G.EMPLID
AND E.EXT_ORG_ID = H.EXT_ORG_ID
AND H.EFFDT=(SELECT MAX(EFFDT) FROM PS_EXT_ORG_TBL H1
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                    AND H.EFF_STATUS=H1.EFF_STATUS
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                    AND H.LS_SCHOOL_TYPE=H1.LS_SCHOOL_TYPE
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                    AND H.CITY=H1.CITY
                    AND H.STATE=H1.STATE )
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Do ORACLE support indexing on the columns with Hebrew Data

Hello Forum,
I was working on an assignment with schemas containing Hebrew Data.
Can i create indexes on the columns containing Hebrew Language data?
Thanks
Priyank Jain

Varchar2; is something difficult for me. Reason why is I need to make change in my application throughout to accept this design change.
My need of Index on Hebrew Data:
Basically I am going to implement a Full-Text Search environment. For full-text searching; I am having a plugin which implements Lucene Algorithm of Indexing.
The Index writing will not be useful until the table is indexed and well-functional.
"But note that standard indexes will be sorted according to binary order of Hebrew letters in Unicode."
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Thanks
Priyank Jain

How to create a domain index on NCLOB Column

hi all,
My database version is 10.2.0.1.
Any body know how to create a domain index on nclob column.
SQL> alter table test add (nclob1 nclob);
Table altered.
SQL> CREATE INDEX test_nclob ON test (nclob1) indextype is ctxsys.context
2 /
CREATE INDEX test_nclob ON test (nclob1) indextype is ctxsys.context
ERROR at line 1:
ORA-29855: error occurred in the execution of ODCIINDEXCREATE routine
ORA-20000: Oracle Text error:
DRG-10509: invalid text column: NCLOB1
ORA-06512: at "CTXSYS.DRUE", line 160
ORA-06512: at "CTXSYS.TEXTINDEXMETHODS", line 364Regards
Singh

Any body know how to create a domain index on nclob columnNot possible per design/documentation:
The column that you specify must be one of the following types: CHAR, VARCHAR, VARCHAR2, BLOB, CLOB, BFILE, XMLType, or URIType.
«

More than one index for a column.

Hi,
I am trying to create more than one index for a particular column of the table.But oracle does not allow more than one index for a column.
I just want to make sure whether we can add more than one index for a column
and if yes what are the scenarios.
Because as far as i know some database allows more than one index for a single column.

You cannot create more than one index for the same column(s).This is not so true Nicolas. Look at following example:
SQL> create index idx_mytest_id on mytest(id);
Index created.
SQL> create index idx_mytest_id_desc on mytest(id desc);
Index created.
SQL> create index idx_fbi_mytest_id_upper on mytest(upper(id));
Index created.
SQL> create index idx_fbi_mytest_id_upper_desc on mytest(upper(id) desc);
Index created.
SQL> create index idx_fbi_mytest_id_lower_id on mytest(lower(id));
Index created.
SQL> create index idx_fbi_mytest_id_lower_id_dsc on mytest(lower(id) desc);
Index created.
SQL> create index idx_fbi_mytest_id_tr_up on mytest(trunc(upper(id)));
Index created.
-- I can still continue but for this example this will be enough
SQL> select index_name from dba_indexes where table_name = 'MYTEST';
INDEX_NAME
IDX_MYTEST_ID
IDX_FBI_MYTEST_ID_UPPER
IDX_MYTEST_ID_DESC
IDX_FBI_MYTEST_ID_UPPER_DESC
IDX_FBI_MYTEST_ID_LOWER_ID
IDX_FBI_MYTEST_ID_LOWER_ID_DSC
IDX_FBI_MYTEST_ID_TR_UP
7 rows selected.You can see 7 indexes for one column (ID) and I could still continue...
So according this test we can say you can't create more than one index for one column (or the same group of columns in case of composite index) with same condition(s).
Message was edited by:
Ivan Kartik
Or simplified: you can't create the same index for same column(s) twice :-)

How to compare index names and columns from different user?

I am using below query to compare two indexes from 2 different users but even though index name and columns are same... result shows me they are different.. what I am doing wrong? Thanks
WITH t AS
        (SELECT COUNT (DISTINCT index_owner || index_name || indexed_cols)
                   cnt
           FROM ( SELECT index_owner,
                          index_name,
                          listagg (column_name, ',')
                             WITHIN GROUP (ORDER BY column_position)
                             indexed_cols
                     FROM dba_ind_columns
                    WHERE index_name='XPKTBL_A'
                 GROUP BY index_owner, index_name))
SELECT CASE
          WHEN cnt > 1 THEN 'Indexes are different'
          WHEN cnt = 0 THEN 'Indexes dont exist'
          WHEN cnt > 1 THEN 'Indexes are identical'
       END
          commnt
FROM t
Result:
Indexes are different
but Actually if you check below they are same After when I run this query:
SELECT index_owner,
         index_name,
         listagg (column_name, ',') WITHIN GROUP (ORDER BY column_position)
            indexed_cols
    FROM dba_ind_columns
   WHERE index_name='XPKTBL_A'
GROUP BY index_owner, index_name;
Result:
Index_owner
Index_name
Index_cols
USER1
XPKTBL_A
FIELD_A1
USER2
XPKTBL_A
FIELD_A1

Hi,
Erhan_toronto wrote:
I am using below query to compare two indexes from 2 different users but even though index name and columns are same... result shows me they are different.. what I am doing wrong? Thanks
WITH t AS
        (SELECT COUNT (DISTINCT index_owner || index_name || indexed_cols)
So index_owner is 'USER1' in one case, and 'USER2' in the other; right?
A string that starts with 'USER1' will be distinct from a string that starts with 'USER2', no matter what the rest of the string contains. Maybe you don't want to compare the owners, or maybe you meant to use some other column (such as table_name) instead of index_owner).
I hope this answers your question.
If not, post a little sample data (CREATE TABLE, CREATE INDEX and CONNECT statements), and also post the results you want from that data.
Explain, using specific examples, how you get those results from that data.
Always say which version of Oracle you're using (e.g., 11.2.0.2.0).
See the forum FAQ: https://forums.oracle.com/message/9362002

Oracle 11g function based columns - deterministic function or not?

Hi all, here is my situation:
I added function based column in my table and created index on this column.
I need this since in my ADF application, I need to be able to sort by this column.
The function (that this column is based on) I had to make it DETERMINISTIC (otherwise it can not be done).
So far so good.
My function is accepting 3 parameters (all NUMBERs) which are practically 3 primary keys from 3 different tables. Based on which key is present, my function is returning "Code" - column (VARCHAR2) from any of those 3 tables. And for sure "Code" can change in any of those table.
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-Should I update the function and make it nondeterministic? Will it still work? Will the index be valid if the function is nondeterministic?
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-If I leave i as deterministic - somehow the result is cached. Will my function always going to be re-executed for each row (having on mind it is not really deterministic)?
-Is there better solution than (function based column and index on it) in my case?
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OK, Damorgan, here are some more details:
Versin Numbers:
Oracle Database 11g Enterprise Edition Release 11.1.0.7.0 - 64bit Production
PL/SQL Release 11.1.0.7.0 - Production
TABLE:
alter table MY_VIRTUAL_COLUMN add dispatch_customer_name GENERATED ALWAYS AS (get_dispatch_customer_name(disloc_id, cus_id, cusloc_id)) VIRTUAL;
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CREATE OR REPLACE FUNCTION get_dispatch_customer_name(p_disloc_id NUMBER,
                                                      p_cus_id    NUMBER,
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   RETURN VARCHAR2 DETERMINISTIC IS
   v_result VARCHAR2(1000) := NULL;
BEGIN
   IF p_cus_id IS NULL THEN
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      ELSE
         SELECT l.name || ' (' || l.code || ')'
           INTO v_result
           FROM customer_locations l
          WHERE l.cusloc_id = p_cusloc_id;
      END IF;
   ELSE
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        INTO v_result
        FROM customers s
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   END IF;
   RETURN v_result;
EXCEPTION
   WHEN OTHERS THEN
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Thanks, Vesna

How to create a index on a column with type clob

how to create a index on a column with type clob

You should have a look to Oracle Text to check if Oracle Text indexing features can meet your needs:
http://download.oracle.com/docs/cd/E11882_01/server.112/e16508/cncptdev.htm#CNCPT1537

Multipal indexes on one column

Hi,
I have one table and in that table there are 5 columns. One column has 3 indexes and another column has 2 indexes.
I want to know that if i create more indexes on one column, will performance of that database increase?
Or if i remove the indexes means that if i keep one index on one column, will performance of that database decrease?
Please suggest me what should i do for these indexes?
Thanks in advance.
Anand

Performance is not increased just by adding indexes, it could even degrade if indexes are bad planned.
A candidate column for indexing is the column mentioned on the where clause of a query. Once the candidate columns has been selected, the second filter is how selective it is, if it can be highly selective (ideal case unique values) then it can be indexed, otherwise (uneven distribution or low cardinality) it cannot be indexed by the regular method, on an uneven distribution column statistics have to be gathered; and on the low cardinality a bitmap index is advisable.
There are many other circumstances where an index is not quite advisable, if you query by expression:
where upper(column)
or
where numeric_col = '213'
then you may have surprises finding that index is not being used. There are other tricks like query rewrite or function based index, but instead of going forward an specific statement has to be made on your side specifying concrete circumstances where you want to implement indexes.
~ Madrid.

Multi-column Index vs One index for each column

Hello everyone,
i have one table about 20 000 000 rows, some developers have to generate reports on it and i want to create indexes on this table.
The table has 34 columns, no primary key, no unique keys.
The "where..." clause of the reports usually use 8 columns but some reports uses 8 + some other columns.
can any one help me on what kind of indexes do i have to create?
1. one index for each column used in "where clause"
2. one index for 8 columns and some other indexes for other used columns
3. one index for all columns
or something else etc...
br flag

i have one table about 20 000 000 rows, some developers have to generate reports on it and i want to create indexes on this table.
The table has 34 columns, no primary key, no unique keys.
The "where..." clause of the reports usually use 8 columns but some reports uses 8 + some other columns.
can any one help me on what kind of indexes do i have to create?
1. one index for each column used in "where clause"
2. one index for 8 columns and some other indexes for other used columns
3. one index for all columns
or something else etc...What's the version of your data base? what kind of database you have, DWH or OTLP? The answer might depend on the type of database as far as bitmap indexes might suit or might not depending if you are runing DWH or OLTP kind of database
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1) are all those where clause equalities (where col1 = and col2 =) or there are inequalities?
2) could you evaluate the most repetitive columns?
3) could you know the column that could have the best clustering factor (the column which most follow a certain order in the table)
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2) put the columns that are used in equalitity predicate first
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Best regards
Mohamed Houri
www.hourim.wordpress.com

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Exception              CX_SY_DYNAMIC_OSQL_SEMANTICS
No.   Ty.          Program                             Include                             Line
      Name
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    WHERE LANGU EQ 'E'.
My sap version:
EHP4 FOR SAP ERP 6.0 / NW7.01
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Do you know any note or solution to resolve this problem.
Best regards,
Jacek Witczak

Hi, I came back to working on "Dunning by collection strategy with BRFplus". According to your sugestions, I raised the level of components:
SAP_BASIS Level 09
SAP_ABA level 09
PI_BASIS level 09
SAP_BW level 09
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Shoudl we raise any other components? Maybe you know note, which resolve this problem?

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Hi,
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How can i do that......

As mentioned this is a java forum not a mysql forum, but as I know the answer - you can't create an index directly on a view in mysql.

How to enter a data into the specified column and row in a created table

Hi,
I want to enter some data to specified column and row in a already created table. Please let me know how to do this.
Regards
Shivakumar Singh

A table is just a 2D array of strings. Keep it in a shift register and use "replace array element" to modify the desired entry programmatically.
If you want to modify it manually and directly from the front panel, make it into a control and type directly into the desired element. (In this case your program would need to write to it using a local variable).
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LabVIEW Champion . Do more with less code and in less time .
Attachments:
ChangeTableEntries.vi ‏41 KB

Oracle 11g bug for column ambigously defined error

I have below format query running on Oracle 10g without any issues
select col1
from (select col1
from (select 'A' col1
from dual)
) v1
inner join (select col1 as col2
from (select 'A' col1
from dual)
) v2
on (v1.col1=v2.col2);
When I run the exact same query on Oracle 11g I get column ambiguously defined error. But when I change the query to as below it works fine on 11g
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from (select col1
from (select 'A' col1
from dual)
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inner join (select col1 as col2
from (select 'A' col1
from dual)
) v2
on (v1.col1=v2.col2);
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I'd tend to agree that this seems to be a bug in 11.1.0.7 (at least, that's the version I'm running it in)
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SELECT v1.col1
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(SELECT col1 FROM
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) v1
INNER JOIN
(SELECT col1 AS col2 FROM
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) v2
     ON (col1=col2);works fine. Using the old join syntax also seems to work fine
SELECT col1
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(SELECT col1 FROM
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) v1,
(SELECT col1 AS col2 FROM
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) v2
WHERE (col1=col2);So it appears that something in the SQL 99 parser is broken. Have you logged a bug in Metalink?
Justin

Oracle Indexing on Specified Columns

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