Index on LFA1 for STCD1..URGENT..!!!!

HI All,
IN transaction FBL1N, F4 help for vendor based on Tax code 1 is taking lot of time. After analysing SQL trace on this i understand that Index needs to be created on LFA1 table for STCD1.
Can anyone please help me out as to what all fields i need to include in the index. Is it that i have to include only STCD1 in the index?
Any pointers on this would be appriciated.
Thanks in advance.
-Sanjay

hai
kulkarni,
if u want to retrieve the data based on stdc1 only , then u should create a secondary index based on that field. if u want to use any other combination of fields other than primary key with stdc1, then it is better to create an index on those combination of fields rather than stdc1 only.
Reward points if useful,
thank you
G.V.K.Prasad
Edited by: PRASAD GVK on Apr 17, 2008 7:50 AM

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Need to generate a Index xml file for corresponding Report PDF file.

Need to generate a Index xml file for corresponding Report PDF file.
Currently in fusion we are generating a pdf file using given Rtf template and dataModal source through Ess BIPJobType.xml .
This is generating pdf successfully.
As per requirement from Oracle GSI team, they need index xml file of corresponding generated pdf file for their own business scenario.
Please see the following attached sample file .
PDf file : https://kix.oraclecorp.com/KIX/uploads1/Jan-2013/354962/docs/BPA_Print_Trx-_output.pdf
Index file : https://kix.oraclecorp.com/KIX/uploads1/Jan-2013/354962/docs/o39861053.out.idx.txt
In R12 ,
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     PrintInvoiceThread :
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               out.println(" <totaldocuments>${VAR_TOTAL_DOCS}</totaldocuments>");
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out.println("<xapi:customcontents>");
XMLDocument idxDoc = new XMLDocument();
idxDoc.setEncoding("UTF-8");
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idxDoc = null;
out.println("</xapi:customcontents>");
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Is there any similar java library which do the same thing in fusion .
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You can find the steps here.
http://weblogic-wonders.com/weblogic/2009/11/29/plan-xml-usage-for-message-driven-bean/
http://weblogic-wonders.com/weblogic/2009/12/16/invalidation-interval-secs/

For one Urgent Change during performing the Approval(chnging the status to 'To be Tested') system does not recognize any changes using the CTS WBS BOM in the development system. The transaction is therefore incorrect or the status was reset by the system.

For one Urgent Change while performing the one of the Approval before changing the status to 'To Be Tested'
We are getting below error.
The system does not recognize any changes using the CTS WBS BOM in the development system. The transaction is therefore incorrect or the status was reset by the system.
COuld anyone please help us to know, How it can be resolved?
We also have this below error.
System Response
If the PPF action is a condition check, the condition is initially considered as not met, and leads to another warning, an error message, or status reset, depending on the configuration.
If the PPF action is the execution of a task in the task list, and the exception is critical, there is another error message in the document.
Procedure
The condition cannot be met until the cause is removed. Analyze all messages in the transaction application log.
Procedure for System Administration
Analyze any other messages in the task list application log, and the entries for the object /TMWFLOW/CMSCV
Additional Information:
System cancel RFC destination SM_UK4CLNT005_TRUSTED, Call TR_READ_COMM:
No authorization to log on as a trusted system (Tr usted RC=0).
/TMWFLOW/TU_GET_REQUEST_REMOTE:E:/TMWFLOW/TRACK_N:107
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If you are in Test System, you can use function module AA_AFABER_DELETE to totally delete the depreciation area (tcode SE37, specify chart of depreciation and depreciation area), After that recreate your depreciation area and run AFBN. But before you do that, have you created a retirement transaction type that limits the posting on your new depreciation area? If not create one.
Hope this helps.
Thanks!
Jhero

Auto-indexing is slow for arrays with 1 dimensions

Hi,
I was looking at the performance of operations on all individual elements in 3D arrays, especially the difference between auto-indexing (left image) and manual-indexing (right image, calling "Index array" and "Replace array subset" in the innermost loop). I'm a bit puzzled by the results and post it here for discussion and hopefully somebody's benefit in the future.
Left: auto-indexing; right: manual-indexing
In the tests I added a different random number to all individual elements in a 3D array. I found that auto-indexing is 1.2 to 1.5 times slower than manual-indexing. I also found that the performance of auto-indexing is much more dependent on the size the dimensions: an array with 1000x200x40 elements is 20% slower than an array with 1000x40x200 elements. For manual-indexing there is hardly any difference. The detailed results can be found at the end of this post.
I was under the impression that auto-indexing was the preferred method for this kind of operation: it achieves exactly the same result and it is much clearer in the block diagram. I also expected that auto-indexing would have been optimized in LabView, but the the tests show this is clearly not the case.
What is auto-indexing doing?
With two tests I looked at how auto-index works.
First, I looked if auto-indexing reorganizes the data in an inefficient way. To do this I made a method "fake-auto-indexing" which calls "Array subset" and "Reshape array" (or "Index array" for a 1D-array) when it enters _every_ loop and calls "Replace array subset" when exiting _every_ loop (as opposed to manual-indexing, where I do this only in the inner loop). I replicated this in a test (calling it fake-auto-indexing) and found that the performance is very similar to auto-indexing, especially looking at the trend for the different array lengths.
Fake-auto-indexing
Second, I looked if Locality of reference (how the 3D array is stored in memory and how efficiently you can iterate over that) may be an issue. Auto-indexing loops over pages-rows-columns (i.e. pages in the outer for-loop, rows in the middle for-loop, columns in the inner for-loop). This can't be changed for auto-indexing, but I did change it for manual and fake-indexing. The performance of manual-indexing is now similar to auto-indexing, except for two cases that I can't explain. Fake-auto-indexing performs way worse in all cases.
It seems that the performance problem with auto-indexing is due to inefficient data organization.
Other tests
I did the same tests for 1D and 2D arrays. For 1D arrays the three methods perform identical. For 2D arrays auto-indexing is 15% slower than manual-indexing, while fake-auto-indexing is 8% slower than manual-indexing. I find it interesting that auto-indexing is the slowest of the three methods.
Finally, I tested the performance of operating on entire columns (instead of every single element) of a 3D array. In all cases it is a lot faster than iterating over individual elements. Auto-indexing is more than 1.8 to 3.4 times slower than manual-indexing, while fake-auto-indexing is about 1.5 to 2.7 times slower. Because of the number of iterations that has to be done, the effect of the size of the column is important: an array with 1000x200x40 elements is in all cases much slower than an array with 1000x40x200 elements.
Discussion & conclusions
In all the cases I tested, auto-indexing is significantly slower than manual-indexing. Because auto-indexing is the standard way of indexing arrays in LabView I expected the method to be highly optimized. Judging by the tests I did, that is not the case. I find this puzzling.
Does anybody know any best practices when it comes to working with >1D arrays? It seems there is a lack of documentation about the performance, surprising given the significant differences I found.
It is of course possible that I made mistakes. I tried to keep the code as straightforward as possible to minimize that risk. Still, I hope somebody can double-check the work I did.
Results
I ran the tests on a computer with a i5-4570 @ 3.20 GHz processor (4 cores, but only 1 is used), 8 GB RAM running Windows 7 64-bit and LabView 2013 32-bit. The tests were averaged 10 times. The results are in milliseconds.
3D-arrays, iterate pages-rows-columns
pages x rows x cols : auto    manual fake
   40 x 200 x 1000 : 268.9   202.0   268.8
   40 x 1000 x 200 : 276.9   204.1   263.8
200 x   40 x 1000 : 264.6   202.8   260.6
200 x 1000 x   40 : 306.9   205.0   300.0
1000 x   40 x 200 : 253.7   203.1   259.3
1000 x 200 x   40 : 307.2   206.2   288.5
100 x 100 x 100 : 36.2    25.7    33.9
3D-arrays, iterate columns-rows-pages
pages x rows x cols : manual fake
   40 x 200 x 1000 : 277.6   457
   40 x 1000 x 200 : 291.6   461.5
200 x   40 x 1000 : 277.4   431.9
200 x 1000 x   40 : 452.5   572.1
1000 x   40 x 200 : 298.1   460.4
1000 x 200 x   40 : 460.5   583.8
100 x 100 x 100 : 31.7    51.9
2D-arrays, iterate rows-columns
rows x cols : auto     manual   fake
200 x 20000 : 123.5    106.1    113.2
20000 x   200 : 119.5    106.1    115.0
10000 x 10000 : 3080.25 2659.65 2835.1
1D-arrays, iterate over columns
cols   : auto manual fake
500000 : 11.5 11.8    11.6
3D-arrays, iterate pages-rows, operate on columns
pages x rows x cols : auto    manual fake
   40 x 200 x 1000 : 83.9   23.3     62.9
   40 x 1000 x 200 : 89.6   31.9     69.0
200 x   40 x 1000 : 74.3   27.6     62.2
200 x 1000 x   40 : 135.6   76.2    107.1
1000 x   40 x 200 : 75.3   31.2     68.6
1000 x 200 x   40 : 133.6   71.7    108.7
100 x 100 x 100 : 13.0    5.4      9.9
VI's
I attached the VI's I used for testing. "ND_add_random_number.vi" (where N is 1, 2 or 3) is where all the action happens, taking a selector with a method and an array with the N dimensions as input. It returns the result and time in milliseconds. Using "ND_add_random_number_automated_test.vi" I run this for a few different situations (auto/manual/fake-indexing, interchanging the dimensions). The VI's starting with "3D_locality_" are used for the locality tests. The VI's starting with "3D_norows_" are used for the iterations over pages and columns only.
Attachments:
3D_arrays_2.zip ‏222 KB

Robert,
the copy-thing is not specific for auto-indexing. It is common for all tunnels. A tunnel is first of all a unique data space.
This sounds hard, but there is an optimization in the compiler trying to reduce the number of copies the VI will create. This optimization is called "in-placeness".
The in-placeness algorithm checks, if the wire passing data to the is connected to anything else ("branch"). If there is no other connection then the tunnel, chance is high that the tunnel won't create an additional copy.
Speaking of loops, tunnels always copies. The in-placeness algorithm cannot opt that out.
You can do a small test to elaborate on this: Simply wire "0" (or anything less than the array sizy of the input array) to the 'N' terminal.......
Norbert
PS: Auto-indexing is perfect for a "by element" operation of analysis without modification of the element in the array. If you want to modify values, use shift registers and Replace Array Subset.
CEO: What exactly is stopping us from doing this?
Expert: Geometry
Marketing Manager: Just ignore it.

What index is suitable for a table with no unique columns and no primary key

alpha
beta
gamma
col1
col2
col3
100
1
-1
a
b
c
100
1
-2
d
e
f
101
1
-2
t
t
y
102
2
1
j
k
l
Sample data above and below is the dataype for each one of them
alpha datatype- string
beta datatype-integer
gamma datatype-integer
col1,col2,col3 are all string datatypes.
Note:columns are not unique and we would be using alpha,beta,gamma to uniquely identify a record .Now as you see my sample data this is in a table which doesnt have index .I would like to have a index created covering these columns (alpha,beta,gamma) .I
beleive that creating clustered index having covering columns will be better.
What would you recommend the index type should be here in this case.Say data volume is 1 milion records and we always use the alpha,beta,gamma columns when we filiter or query records
what index is suitable for a table with no unique columns and primary key?
col1
col2
col3
Mudassar

Many thanks for your explanation .
When I tried querying using the below query on my heap table the sql server suggested to create NON CLUSTERED INDEX INCLUDING columns ,[beta],[gamma] ,[col1]
,[col2] ,[col3]
SELECT [alpha]
,[beta]
,[gamma]
,[col1]
,[col2]
,[col3]
FROM [TEST].[dbo].[Test]
where [alpha]='10100'
My question is why it didn't suggest Clustered INDEX and chose NON clustered index ?
Mudassar

Index is missing for a specific Primary key.

Hi All,
Index is missing for a specific Primary key but for other PKs index is available (verified in metadata, USER_INDEXES).
Status of problematic PK is enabled. This issue is only in one environment and other envs index is associated with this PK without any issue.
Could you please advice, what could the possible reason?
Regards,
Narasimha.

What other indexes are on your table? You do not need a unique index to enforce a primary key:
> create table bc (col1 number, col2 number);
Table created.
> create index bc_ix on bc (col1, col2);
Index created.
> alter table bc add constraint bc_pk primary key (col1) using index bc_ix;
Table altered.
> create unique index bc_pk on bc (col1);
Index created.
> select index_name, uniqueness from user_indexes where table_name = 'BC';
INDEX_NAME                     UNIQUENES
BC_IX                          NONUNIQUE
BC_PK                          UNIQUE
> select constraint_name, constraint_type from user_constraints where table_name = 'BC';
CONSTRAINT_NAME                C
BC_PK                          P
> drop index bc_pk;
Index dropped.
> select index_name, uniqueness from user_indexes where table_name = 'BC';
INDEX_NAME                     UNIQUENES
BC_IX                          NONUNIQUE
> select constraint_name, constraint_type, index_name from user_constraints where table_name = 'BC';
CONSTRAINT_NAME                C INDEX_NAME
BC_PK                          P BC_IX
>

Auto index entry generation for a range of sentences?

Is there any way to mark a range of sentences and associate it with a particular index entry? For a lengthy book, I don't think one can really expect the text to never change, hence regenerating the index needs to continue to work even if a bit of text was added which pushes one of the range of sentences onto the next page.
The closest thing I found was to mark the beginning of the range of sentences with an index entry for "the next 1 paragraph," but this doesn't seem to work. In my example document, http://goldfinches.org/InDesign/Failed%20Index%20Entry.indd the "Dog" entry spans two pages, but only 1 paragraph, and yet the index that is generated only has the first page in it.

Greg,
There is no way to say, index from here to here. But you can use any of the range designators. From what you're describing, the most likely to be useful is the one that indexes up to the next instance of a particular paragraph style.
Dave

Which Event Classes i should use for finding good indexs and statistics for queries in SP.

Dear all,
I am trying to use pro filer to create a trace,so that it can be used as workload in
"Database Engine Tuning Advisor" for optimization of one stored procedure.
Please tel me about the Event classes which i should use in trace.
The stored proc contains three insert queries which insert data into a table variable,
Finally a select query is used on same table variable with one union of the same table variable, to generate a sequence for records based on certain condition of few columns.
There are three cases where i am using the above structure of the SP, so there are three SPS out of three , i will chose one based on their performance.
1) There is only one table with three inserts which gets into a table variable with a final sequence creation block.
2) There are 15 tables with 45 inserts , which gets into a tabel variable with a final
sequence creation block.
3)
There are 3 tables with 9 inserts , which gets into a table variable with a final
sequence creation block.
In all the above case number of record will be around 5 lacks.
Purpose is optimization of queries in SP
like which Event Classes i should use for finding good indexs and statistics for queries in SP.
yours sincerely

"Database Engine Tuning Advisor" for optimization of one stored procedure.
Please tel me about the Event classes which i should use in trace.
You can use the "Tuning" template to capture the workload to a trace file that can be used by the DETA. See
http://technet.microsoft.com/en-us/library/ms190957(v=sql.105).aspx
If you are capturing the workload of a production server, I suggest you not do that directly from Profiler as that can impact server performance. Instead, start/stop the Profiler Tuning template against a test server and then script the trace
definition (File-->Export-->Script Trace Definition). You can then customize the script (e.g. file name) and run the script against the prod server to capture the workload to the specified file. Stop and remove the trace after the workload
is captured with sp_trace_setstatus:
DECLARE @TraceID int = <trace id returned by the trace create script>
EXEC sp_trace_setstatus @TraceID, 0; --stop trace
EXEC sp_trace_setstatus @TraceID, 2; --remove trace definition
Dan Guzman, SQL Server MVP, http://www.dbdelta.com

I am suspicious about my billing. What am I going to do? Awaiting for your urgent reply.

I am suspicious about my billing. What am I going to do? Awaiting for your urgent reply.

These are user-to-user forums, you are not talking to Apple here.
As you don't say what you are supicious about it's difficult to know what problem it is that you think that you have.
You can check the purchase history on your account via the Store > View My Account (Store > View My Apple ID on iTunes 11) drop-down menu option on your computer's iTunes), though I'm not sure if that shows in-app purchases and/or auto-renewing subscriptions . If you haven't purchased anything and you haven't added or changed your credit card details (when you do then a small temporary store holding charge may be applied to check that the details are correct and valid, which should disappear within a few days) then you can contact iTunes support via this page if you have charges that you don't think that you should have : http://www.apple.com/support/itunes/contact/ - click on Contact iTunes Store Support on the right-hand side of the page, then Purchases, Billing & Redemption

Allow indexing service to index this disk for fast file searching

Hello,
I'm using Oracle on Win 2000, I have lately found out that the option "Compress drive to save disk space"
is not supported in Oracle.
When I've opened the drive specifications on the properties dialog, I found also another option called "Allow indexing service to index this disk for fast file searching".
My question are;
1. Should I turn it off?
2. Same question when the indexed directories does not include Oracle files?
3. Same question, when the indexing service is set to off?
Thanks,
Tal Olier ([email protected])

If this is a production machine, I'd definitely turn this off. Hopefully, no one is going to be searching for particular files on a production server-- they'll know where to go. You probably don't want any unnecessary background processes using up CPU or RAM either.
If this is a development machine, the developer may be searching for files with some frequency. If that's the case, it may be worth it to keep this service enabled.
I'm not aware of any Oracle issues when this service is running, but I'm paranoid enough not to trust it on a production box. If you're running on a dev box, you shouldn't have problems, particularly if you're not indexing Oracle files.
Justin

TREX Index creation help for Bex Portfolio folders

Hi
I have created a TREX search index on a folder structure within our BI Bex Portfolio. The problem that I am enountering is that the index will only pick up documents and links created within these folders and it does not seem to index publshed links to queries by users using the broadcasting features of query designer. Does anybody know why this is and how to get it to also pick up these BW objects?
Thanks

Hi Aaron
The TREX should be able to index the titles (cm_displayname) of the links. Do you know if the titles of the links are searchable?
But I dont think the content can be indexed, unless you publish the reports as pdf-files instead of links, because the TREX cannot reproduce the report and index it afterwards. The TREX cannot index (crawl) javascript for instance, because it cannot perform that kind of client-like behaviour.
Kind regards,
Martin Søgaard

Query not choosing right index and running for long

The database version is 10.2.0.3 on AIX6.1
I'm facing a strange issue. The application loads the data first into the database and then switch to query the same tables in the database. These all run as a single process. So, the select queries are unable to choose the right indexes due to CBO. If the query has choosen the wrong index it runs for hours (4 to 5 hours) for just querying a single table with 265,000 records. If I run the statistics just after data load and before the select query starts, the process runs fast and finish soon. Could someone let me know why does it take that much long to run a query with wrong indexes?. The query is not complex and it will access a single table with MAX function in the sub-query. It usally takes 15 to 25 msec to return the records.

Boochi wrote:
How long does it take to read 1000 blocks?. Does it take 4 or 5 hours?.You mentioned 1,000 blocks, 265,000 rows, and a max() subquery.
Let's pretend that the subquery executes once for every row in the table, and scans the whole table checking every row: that 265,001,000 block visits, comparing 70 billion values. That's allowed to take a bit of CPU.
Four or five hours seems quite high - but not completely insane, especially since we don't know what else is going on at the time, whether or not you're managing to keep all those blocks buffered, how many columns there are in the row, and where in the row the relevant column might be.
An execution plan, or even the output from "set autotrace traceonly" could be quite instructive.
Regards
Jonathan Lewis
http://jonathanlewis.wordpress.com
http://www.jlcomp.demon.co.uk
"Science is more than a body of knowledge; it is a way of thinking"
Carl Sagan
To post code, statspack/AWR report, execution plans or trace files, start and end the section with the tag {noformat}{noformat} (lowercase, curly brackets, no spaces) so that the text appears in fixed format.

Is aggregate DB index is required for query performance

Hi,
Cube mange tab when i check for the aggregate DB index it shows red, here my doubt is, is the DB index is required for query performance
is the check statics should be in green?
Please let me know
Regards,
Kiran

Hi,
Yes it improves the reports performance..
Using the Check Indexes button, you can check whether indexes already exist and whether these existing indexes are of the correct type (bitmap indexes).
Yellow status display: There are indexes of the wrong type
Red status display: No indexes exist, or one or more indexes are faulty
You can also list missing indexes using transaction DB02, pushbutton Missing Indexes. If a lot of indexes are missing, it can be useful to run the ABAP reports SAP_UPDATE_DBDIFF and SAP_INFOCUBE_INDEXES_REPAIR.
See SAP Help
http://help.sap.com/saphelp_nw2004s/helpdata/en/80/1a6473e07211d2acb80000e829fbfe/content.htm
Thanks
Reddy

How many SECONDARY INDEXES are created for CLUSTER TABLES?

how many SECONDARY INDEXES are created for CLUSTER TABLES?
please explain.

There seems to be some kind of misunderstanding here. You cannot create a secondary index on a cluster table. A cluster table does not exist as a separate physical table in the database; it is part of a "physical cluster". In the case of BSEG for instance, the physical cluster is RFBLG. The only fields of the cluster table that also exist as fields of the physical cluster are the leading fields of the primary key. Taking again BSEG as the example, the primary key includes the fields MANDT, BUKRS, BELNR, GJAHR, BUZEI. If you look at the structure of the RFBLG table, you will see that it has primary key fields MANDT, BUKRS, BELNR, GJAHR, PAGENO. The first four fields are those that all cluster tables inside BSEG have in common. The fifth field, PAGENO, is a "technical" field giving the sequence number of the current record in the series of cluster records sharing the same primary key.
All the "functional" fields of the cluster table (for BSEG this is field BUZEI and everything beyond that) exist only inside a raw binary object. The database does not know about these fields, it only sees the raw object (the field VARDATA of the physical cluster). Since the field does not exist in the database, it is impossible to create a secondary index on it. If you try to create a secondary index on a cluster table in transaction SE11, you will therefore rightly get the error "Index maintenance only possible for transparent tables".
Theoretically you could get around this by converting the cluster table to a transparent table. You can do this in the SAP dictionary. However, in practice this is almost never a good solution. The table becomes much larger (clusters are compressed) and you lose the advantage that related records are stored close to each other (the main reason for having cluster tables in the first place). Apart from the performance and disk space hit, converting a big cluster table like BSEG to transparent would take extremely long.
In cases where "indexing" of fields of a cluster table is worthwhile, SAP has constructed "indexing tables" around the cluster. For example, around BSEG there are transparent tables like BSIS, BSAS, etc. Other clusters normally do not have this, but that simply means there is no reason for having it. I have worked with the SAP dictionary for over 12 years and I have never met a single case where it was necessary to convert a cluster to transparent.
If you try to select on specific values of a non-transparent field in a cluster without also specifying selections for the primary key, then the database will have to do a serial read of the whole physical cluster (and the ABAP DB interface will have to decompress every single record to extract the fields). The performance of that is monstrous -- maybe that was the reason of your question. However, the solution then is (in the case of BSEG) to query via one of the index tables (where you are free to create secondary indexes since those tables are transparent).

Index (or not) for excluding NULL values in a query

Hello,
I have table that can become very large. The table has a varchar2 column (let's call it TEXT) that can contain NULL values. I want to process only the records that have a value (NOT NULL). Also, the table is continuously expanded with newly inserted records. The inserts should suffer as little performance loss as possible.
My question: should I use an index on the column and if so, what kind of index?
I have done a little test with a function based index (inspired by this Tom Kyte article: http://tkyte.blogspot.com/2006/01/something-about-nothing.html):
create index text_isnull_idx on my_table(text,0);
I notice that if I use the clause WHERE TEXT IS NULL, the index is used. But if I use a clause WHERE TEXT IS NOT NULL (which is the clause I want to use), a full table scan is performed. Is this bad? Can I somehow improve the speed of this selection?
Thanks in advance,
Frans

I build a test case with very simple table with 2 columns and it shows that FTS is better than index access even when above ratio is <= 0.01 (1%):
DROP TABLE T1;
CREATE TABLE T1
           C1 VARCHAR2(100)
          ,C2 NUMBER
INSERT INTO T1 (SELECT TO_CHAR(OBJECT_ID), ROWNUM FROM USER_OBJECTS);
BEGIN
     FOR I IN 1..100 LOOP
          INSERT INTO T1 (SELECT NULL, ROWNUM FROM USER_OBJECTS);
     END LOOP;
END;
CREATE INDEX T1_IDX ON T1(C1);
ANALYZE TABLE T1 COMPUTE STATISTICS
     FOR TABLE
     FOR ALL INDEXES
     FOR ALL INDEXED COLUMNS
SET AUTOTRACE TRACEONLY
SELECT
          C1, C2
     FROM T1 WHERE C1 IS NOT NULL;
3864 rows selected.
real: 1344
Execution Plan
   0      SELECT STATEMENT Optimizer=CHOOSE (Cost=59 Card=3864 Bytes=30912)
   1    0   TABLE ACCESS (FULL) OF 'T1' (Cost=59 Card=3864 Bytes=30912)
Statistics
          0 recursive calls
          0 db block gets
       2527 consistent gets
       3864 rows processed
BUT
SELECT
     --+ FIRST_ROWS
          C1, C2
     FROM T1 WHERE C1 IS NOT NULL;
3864 rows selected.
real: 1296
Execution Plan
   0      SELECT STATEMENT Optimizer=HINT: FIRST_ROWS (Cost=35 Card=3864 Bytes=30912)
   1    0   TABLE ACCESS (BY INDEX ROWID) OF 'T1' (Cost=35 Card=3864 Bytes=30912)
   2    1     INDEX (FULL SCAN) OF 'T1_IDX' (NON-UNIQUE) (Cost=11 Card=3864)
Statistics
          0 recursive calls
          0 db block gets
       5052 consistent gets
       3864 rows processed
and just for comparison:
SELECT * FROM T1 WHERE C1 IS NULL;
386501 rows selected.
real: 117878
Execution Plan
   0      SELECT STATEMENT Optimizer=CHOOSE (Cost=59 Card=386501 Bytes=3092008)
   1    0   TABLE ACCESS (FULL) OF 'T1' (Cost=59 Card=386501 Bytes=3092008)
Statistics
          0 recursive calls
          0 db block gets
     193850 consistent gets
     386501 rows processedHence you have to benchmark you queries with and w/o index[es]

Index on LFA1 for STCD1..URGENT..!!!!

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