Select Statement Blocking Delete Operation

Hi Experts,
In a Single table am trying to do delete operation but it has been blocked by simple select query.
Database setting : Read Committed Snapshot already set to ON for that database.
Any Idea why SELECT blocking DELETE.
FYI : Before Select statement I could noticed the following setting "set transaction isolation level read committed".
Kindly Advise
Regards,
Nandhu

FYI : Before Select statement I could noticed the following setting "set transaction isolation level read committed".
Hi NandhuJana,
1. Did you read
Uri Dimant's response?
Please try to remove this statement and check again
2. When we ask you for DDL+DML , the idea is to let us the option to (1) reproduce the issue in some cases, (2) get the best information which is the real database structure, queries, etc'. In this case for example I do not see the isolation level statement
in your code and we need it to understand what is happening :-) The order and structure (nested transactions for example) of statements is what important here.
3. you can check your isolet level using one of those options to make sure what is going in your script:
SELECT TRANSACTION_ISOLATION_LEVEL = CASE transaction_isolation_level
WHEN 0 THEN 'Unspecified'
WHEN 1 THEN 'ReadUncommitted'
WHEN 2 THEN 'ReadCommitted'
WHEN 3 THEN 'Repeatable'
WHEN 4 THEN 'Serializable'
WHEN 5 THEN 'Snapshot'
END
FROM sys.dm_exec_sessions
where session_id = @@SPID
GO
DBCC USEROPTIONS WITH NO_INFOMSGS
GO
I hope this is helpful :-)
Ronen Ariely
[Personal Site] [Blog] [Facebook]

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How can write select statement inside case operator

Hi all,
I like to write a query which get result from other table in case operator.
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sorry, but thats funny.
You ask for case with subquery and choosed a solution with decode as correct.
Furthermore, the solution proposed might not be so useful.
First of all many people prefer case over decode, because of understandability and readability of the code (toad has this as a coding rule built in too)
Secondly in this case the decode does nothing. Take a closer look:
select a,b,c from tableA a
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Edited by: chris227 on 12.05.2012 02:12

Bind Variable in SELECT statement and get the value in PL/SQL block

Hi All,
I would like pass bind variable in SELECT statement and get the value of the column in Dynamic SQL
Please seee below
I want to get the below value
Expected result:
select distinct empno ,pr.dept   from emp pr, dept ps where   ps.dept like '%IT' and pr.empno =100
100, HR
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select distinct loc ,pr.dept   from emp pr, dept ps where   ps.dept like '%IT' and pr.empno =100
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----- TABLE LIST
CREATE TABLE EMP(
EMPNO NUMBER,
ENAME VARCHAR2(255),
DEPT VARCHAR2(255),
LOC    VARCHAR2(255)
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INSERT INTO EMP (EMPNO,ENAME,DEPT,LOC) VALUES (200,'TEST1','IT','NYC');
INSERT INTO EMP (EMPNO,ENAME,DEPT,LOC) VALUES (300,'TEST2','MR','NYC');
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COMMIT;
CREATE TABLE COLUMNAMES(
COLUMNAME VARCHAR2(255)
INSERT INTO COLUMNAMES(COLUMNAME) VALUES ('EMPNO');
INSERT INTO COLUMNAMES(COLUMNAME) VALUES ('ENAME');
INSERT INTO COLUMNAMES(COLUMNAME) VALUES ('DEPT');
INSERT INTO COLUMNAMES(COLUMNAME) VALUES ('LOC');
COMMIT;
CREATE TABLE DEPT(
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INSERT INTO DEPT(DEPT,DNAME) VALUES ('HR','HUMAN RESOURCE');
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COMMIT;
PL/SQL BLOCK
DECLARE
TYPE EMPCurTyp IS REF CURSOR;
v_EMP_cursor    EMPCurTyp;
l_col_val           EMP.ENAME%type;
l_ENAME_val       EMP.ENAME%type;
l_col_ddl varchar2(4000);
l_col_name varchar2(60);
l_tab_name varchar2(60);
l_empno number ;
b_l_col_name VARCHAR2(255);
b_l_empno NUMBER;
begin
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select EMPNO aa from EMP
loop
l_empno := rec00.aa;
for rec in (select COLUMNAME as column_name from columnames
loop
l_col_name := rec.column_name;
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l_col_val :=null;
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CLOSE v_EMP_cursor;
END;
END LOOP;
END LOOP;
END;

user1758353 wrote:
Thanks Billy, Would you be able to suggest any other faster method to load the data into table. Thanks,
As Mark responded - it all depends on the actual data to load, structure and source/origin. On my busiest database, I am loading on average 30,000 rows every second from data in external files.
However, the data structures are just that - structured. Logical.
Having a data structure with 100's of fields (columns in a SQL table), raise all kinds of questions about how sane that structure is, and what impact it will have on a physical data model implementation.
There is a gross misunderstanding by many when it comes to performance and scalability. The prime factor that determines performance is not how well you code, what tools/language you use, the h/w your c ode runs on, or anything like that. The prime factor that determines perform is the design of the data model - as it determines the complexity/ease to use the data model, and the amount of I/O (the slowest of all db operations) needed to effectively use the data model.

Delete operation is not working to delete selected row from ADF table

Hi All,
We are working on jdev 11.1.1.5.3. We have one ADF table as shown below. My requirement is to delete a selected row from table, but it is deleting the first row only.
<af:table value="#{bindings.EventCalendarVO.collectionModel}" var="row"
rows="#{bindings.EventCalendarVO.rangeSize}"
emptyText="#{bindings.EventCalendarVO.viewable ? applcoreBundle.TABLE_EMPTY_TEXT_NO_ROWS_YET : applcoreBundle.TABLE_EMPTY_TEXT_ACCESS_DENIED}"
fetchSize="#{bindings.EventCalendarVO.rangeSize}"
rowBandingInterval="0"
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selectionListener="#{bindings.EventCalendarVO.collectionModel.makeCurrent}"
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>
To perform delete operation i have one delete button.
<af:commandToolbarButton
text="Delete"
disabled="#{!bindings.Delete.enabled}"
id="ctb3" accessKey="d"
actionListener="#{AddNewEventBean. *deleteCurrentRow* }"/>
As normal delete operation is not working i am using programatic approach from bean method. This approach works with jdev 11.1.1.5.0 but fails on ver 11.1.1.5.3
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(DCBindingContainer)BindingContext.getCurrent().getCurrentBindingsEntry();
DCIteratorBinding dcItteratorBindings =
bindings.findIteratorBinding("EventCalendarVOIterator");
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ViewObject eventCalVO = dcItteratorBindings.getViewObject();
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eventCalVO.removeCurrentRow();
it is removing first row from table still. Main problem is not giving the selected row as current row. Any one point out where is the mistake?
We have tried the below code as well in deleteCurrentRow() method
RowKeySet rowKeySet = (RowKeySet)this.getT1().getSelectedRowKeys();
CollectionModel cm = (CollectionModel)this.getT1().ggetValue();
for (Object facesTreeRowKey : rowKeySet) {
cm.setRowKey(facesTreeRowKey);
JUCtrlHierNodeBinding rowData = (JUCtrlHierNodeBinding)cm.getRowData();
rowData.getRow().remove();
The same behavior still.
Thanks in advance.
Rechin
Edited by: 900997 on Mar 7, 2012 3:56 AM
Edited by: 900997 on Mar 7, 2012 4:01 AM
Edited by: 900997 on Mar 7, 2012 4:03 AM

JDev 11.1.1.5.3 sounds like you are using oracle apps as this not a normal jdev version.
as it works in 11.1.1.5.0 you probably hit a bug which you should file with support.oracle.com...
Somehow you get the first row instead of the current row (i guess). You should debug your code and make sure you get the current selected row in your bean code and not the first row.
This might be a problem with the bean scope too. Do you have the button (or table) inside a region? Wich scope does the bean have?
Anyway you can try to remove the iterator row you get
public void deleteCurrentRow (ActionEvent actionEvent) { DCBindingContainer bindings =
(DCBindingContainer)BindingContext.getCurrent().getCurrentBindingsEntry();
DCIteratorBinding dcItteratorBindings =
bindings.findIteratorBinding("EventCalendarVOIterator");
dcItteratorBindings.removeCurrentRow();Timo

Operation in Select Statement

Hi,
In an ABAP select statement, how to do operations on two columns of a dictionary transparent table(say division or multiplication on two column values) ?
Reward points will be awarded .
TIA
Regards,
Anindita

hi,
see the below link
i hope it will useful for u .
http://help.sap.com/saphelp_nw04/helpdata/en/62/10a423384746e8bf5f15ccdd36e8b1/content.htm
SELECT AVG(salary) FROM employees
SELECT COUNT(*) FROM employees
SELECT COUNT(DISTINCT employee_name) FROM employees
SELECT employee_name, salary + benefit
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               WHERE salary < 0.8 *
                  ( SELECT MAX( salary ) FROM employees )
Arithmetic Expressions. For all employees that have a salary not exceeding 80% of the salary of the maximum salary of all employees, this query returns the name of the employee and the sum of its salary and its benefit.
reward if its useful
Edited by: p541399 on Feb 28, 2008 5:49 PM

Delete adjacent duplicates how to use in the below select statement

hi i have a problem
i am suing the below select statement
SELECT    a~extno
          a~guid_lclic       " for next select
          e~ctsim
          e~ctsex
*revised spec 3rd
          f~guid_pobj
          f~amnt_flt
          f~amcur
          f~guid_mobj
          e~srvll     "pk
          e~ctsty     "PK
          e~lgreg "PK
INTO TABLE gt_sagmeld
FROM /SAPSLL/LCLIC as a
INNER JOIN /sapsll/tlegsv as e on elgreg = algreg
inner join /sapsll/legcon as f on fguid_lclic = aguid_lclic   " for ccngn1 selection
inner join /sapsll/corcts as g on gguid_pobj = fguid_pobj
                           where   a~extno in s_extno.
sort gt_sagmeld by guid_lclic lgreg ctsty srvll GUID_POBJ GUID_MOBJ.
delete adjacent duplicates from gt_sagmeld comparing guid_lclic lgreg ctsty srvll GUID_POBJ GUID_MOBJ .
now i am confused how to use delete adjacent dupliacate and on which fields
as first table /sal../lclic primary key is guid_lclic
and it is joined to table
legcon by guid_lclci ( not a primary key here)
legcon primary key is guid_legcon
and table 3 legsv by lgreg (pk here)
table 3 has tow more primary key srvll and ctsty also
NOW MY QUESTIO IS TAHT IS I USE ABOVE DELETE ADJACENT STATMENT IT FETCHES 20 LAKH RECORDS
I WANT TO REDUCE IS LET ME KNOW ON WHAT fields i need to use delete adjacen duplicates
or use comparing all fields?
regards
Arora

hi sudha
if u see my select statement is contains four Primary keys
srvll
lgreg
ctsty
guid_lclic
but the next table connected to this table legcon is by guid_pobj and anothe table by guid_mobj
and if i take this gt_sagmeld to another temp table and i find abt 10 lakh uniques guid_pobj
similary 6 lakh guid_mobj so the next slect is hanpering because of this
not COMING TO OUR POINT IF I SORT ONLY BY OUR PRIMARY KEYS NOT TAKING INTO ACCOUNT TEH GUID_POBJ AND GUID_MOBJ
THE ENTRIES ARE VERY LESS BUT IF I TAKE INOT ACCCOUNT IN GT_SAGMELD THE ENTRIES ARE ABT 20 LAKH
SO I AM NOT SURE WHETHER TO TAKNE GUID_POBJ AND GUID_MOBJ INOT ACCOUNT FOR DELECTING ADJACENT DUPLICATES?
HENCE THE QUESTION OF ON WHICH FIRLD DELETE OR COMPARING ALL FIELDS I USE?

FETCHING VALUES IN MULTI RECORD BLOCK FROM ANOTHER TABLE USING SELECT STATEMENT.

Hi,
I have one multi record block in which i want to fetch values
(more then one record) from another table using select statement
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ORA-01422: exact fetch returns more than requested number of rows
Thanks in advance.

In your case I see no reason to use non-database block and to try to populate it from a trigger with a query, instead of using the default forms functionality where you can associate the block and the fields with table, create where clause using bind variables and simply use execute_query() build-in to populate the block. The power of the forms is to use their build-in functionality to interact with the database.
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first_record();
FOR v_tab IN (SELECT *
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:non_db_block_name.field1 := v_tab.col1;
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Hi i am getting error when i write the below select statement, could any one please let me know, how to use CP operator in select statement
my code was
SELECT lifnr name1 FROM lfa1 INTO CORRESPONDING
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Thanks
Srini
Message was edited by: Manish Kumar <spoonfeeding, thread locked by moderator>
Message was edited by: Manish Kumar

either you have select-options with lifnr and name and use them in the below query as
SELECT lifnr name1 FROM lfa1 INTO CORRESPONDING
        FIELDS OF TABLE lt_lfa1
        WHERE lifnr in s_lifnr AND
              name1 in s_name1.
else you need to declare internal tables with structure as below..
DATA: begin of ls_user1,
    sign type c,
    option(2) type c,
    low(90) type c,
    high(90) type c,
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data: lt_lifnr like ls_user1 occurs 0,
         lt_name1 like ls_user1 occurs 0.
and then populate these as
ls_user1-sign = 'I'.
ls_user1-option = 'CP'.
ls_user1-low = '*'. populate with whatever pattern you want
APPEND ls_user1 TO lt_lifnr
similarly do it for NAME1 and use them in the query.

Select statement from a join file deletes the primary records with MS Expl.

Hello,
is reality,
Select statement from a join file deletes the primary records with MS Explorer 6, Firefox not, this with a normal data provider or with a normal "select..." statement.
This is very strange, I should have a.a.s.p. a solution or workaround
Thanks, Franco.
Message was edited by:
fbiaggi

Please see the following excerpt from the online documentation.
http://docs.oracle.com/cd/E11882_01/server.112/e22490/ldr_modes.htm#SUTIL1332
Enabled Constraints
During a direct path load, the constraints that remain enabled are as follows:
NOT NULL
UNIQUE
PRIMARY KEY (unique-constraints on not-null columns)
NOT NULL constraints are checked at column array build time. Any row that violates the NOT NULL constraint is rejected.
Even though UNIQUE constraints remain enabled during direct path loads, any rows that violate those constraints are loaded anyway (this is different than in conventional path in which such rows would be rejected). When indexes are rebuilt at the end of the direct path load, UNIQUE constraints are verified and if a violation is detected, then the index will be left in an Index Unusable state. See "Indexes Left in an Unusable State".

Help in Delete operation

I have a problem when deleting rows from a table. When I created the database the following delete statement worked fine, but now it takes a lot to complete. To delete 600 rows it takes more than 10 minutes. Maybe the transaction log is full, but i don't know how to check the space assigned to it or where is it.
The delete operation is the following one.
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(SELECT event.event_id FROM event WHERE event_TTT.event_id=event.event_id and event.MM_id=1328)

Thank you for your information about statistics. After reading some papers and after checking that automatic statistics are being gathered in my system, I think that my tables do not fulfill the requirements to gather statistics manually ("statistics on tables which are significantly modified during the day"). Maybe I'm wrong. I'll continue reading about this.
Anyway, I've new data about my delete operation. I think it is very slow, but I'll give you the details:
DELETE FROM event_track e
WHERE EXISTS
SELECT
NULL
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WHERE e1.event_id = e.event_id
AND e1.pdep_mission_id = 1328
AND ROWNUM = 1
The is an index on e1.pdep_mission_id.
e1.event_id and e.event_id are primary keys.
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Number of rows on e1 = 120000
Number or rows to delete = 3500
This is the execution plan (with autotrace):
Plan hash value: 660928614
| Id | Operation | Name | Rows | Bytes | Cost (%CPU)| Time |
| 0 | DELETE STATEMENT | | 1 | 254 | 217K (1)| 00:31:20 |
| 1 | DELETE | EVENT_TRACK | | | | |
|* 2 | FILTER | | | | | |
| 3 | TABLE ACCESS FULL | EVENT_TRACK | 119K| 28M| 667 (3)| 00:00:06 |
|* 4 | COUNT STOPKEY | | | | | |
|* 5 | TABLE ACCESS BY INDEX ROWID| EVENT | 1 | 9 | 2 (0)| 00:00:01 |
|* 6 | INDEX UNIQUE SCAN | PK_EVENT271 | 1 | | 1 (0)| 00:00:01 |
Predicate Information (identified by operation id):
2 - filter( EXISTS (SELECT 0 FROM "PDEP"."EVENT" "E1" WHERE ROWNUM=1 AND
"E1"."EVENT_ID"=:B1 AND "E1"."PDEP_MISSION_ID"=1305))
4 - filter(ROWNUM=1)
5 - filter("E1"."PDEP_MISSION_ID"=1305)
6 - access("E1"."EVENT_ID"=:B1)
Estadísticas
11207 recursive calls
26273 db block gets
24517966 consistent gets
23721872 physical reads
4316076 redo size
932 bytes sent via SQL*Net to client
1105 bytes received via SQL*Net from client
6 SQL*Net roundtrips to/from client
12 sorts (memory)
0 sorts (disk)
3518 rows processed
This operation took 2 hours and 5 minutes to complete the deletion of 3500 rows. Do I have to assume that this is correct or maybe I'm doing something wrong ??
Thank you in advance.

Excessive flashback log generates with select statement

Hi everyone;
We have some extractions taken from a "flashback on" database.
Extractions are just select statements but when they are run, database produces excessive flashback logs.
What may be the reason database produce flashback logs with just select statements?
(It's certain that there are no insert-update-delete operations)
Version: 10.2.0.4.3
Thanks...

Do you do heavy update/delete before you select the statements ?
I am not very sure if delayed block cleanout also have the same effect on flashback logs but the output below is leading me to think that way
HR@ORACOS> select * from v$flashback_database_stat;
BEGIN_TIME        END_TIME          FLASHBACK_DATA    DB_DATA REDO_DATA ESTIMATED_FLASHBACK_SIZE
20100527 15:32:53 20100527 15:50:16      875266048 1207132160 2038729728                        0
20100527 14:32:50 20100527 15:32:53      248160256 127295488 450139648               1.3215E+10
20100527 13:32:48 20100527 14:32:50       10452992   15646720    4400640               1.5549E+10
20100527 12:32:43 20100527 13:32:48      745693184 948461568 1311620608               2.2789E+10
20100527 11:25:56 20100527 12:32:43     1262026752 1984741376 2358546432               2.7212E+10
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HR@ORACOS> update base_table_np set y='INVALID';
commit;
4021808 rows updated.
Statistics
       2512 recursive calls
    8341430 db block gets
    4069140 consistent gets
     120569 physical reads
1908471980 redo size
        848 bytes sent via SQL*Net to client
        793 bytes received via SQL*Net from client
          3 SQL*Net roundtrips to/from client
          1 sorts (memory)
          0 sorts (disk)
    4021808 rows processed
HR@ORACOS> set autotrace off;
HR@ORACOS> select * from v$flashback_database_stat;
HR@ORACOS>
BEGIN_TIME        END_TIME          FLASHBACK_DATA    DB_DATA REDO_DATA ESTIMATED_FLASHBACK_SIZE
20100527 15:32:53 20100527 16:00:36     1236664320 2021974016 4019910656                        0
20100527 14:32:50 20100527 15:32:53      248160256 127295488 450139648               1.3215E+10
20100527 13:32:48 20100527 14:32:50       10452992   15646720    4400640               1.5549E+10
20100527 12:32:43 20100527 13:32:48      745693184 948461568 1311620608               2.2789E+10
20100527 11:25:56 20100527 12:32:43     1262026752 1984741376 2358546432               2.7212E+10
HR@ORACOS> set autotrace traceonly statistics
HR@ORACOS> select * from base_table_np;
4021808 rows selected.
Statistics
        139 recursive calls
          0 db block gets
      53908 consistent gets
       4404 physical reads
    1652384 redo size                                                  ------->delayed block cleanout effect
175008833 bytes sent via SQL*Net to client
      88996 bytes received via SQL*Net from client
       8045 SQL*Net roundtrips to/from client
          4 sorts (memory)
          0 sorts (disk)
    4021808 rows processed
HR@ORACOS> set autotrace off
HR@ORACOS> select * from v$flashback_database_stat;    ----flashback data size increases
HR@ORACOS>
BEGIN_TIME        END_TIME          FLASHBACK_DATA    DB_DATA REDO_DATA ESTIMATED_FLASHBACK_SIZE
20100527 15:32:53 20100527 16:01:11     1305264128 2054594560 4021728256                        0
20100527 14:32:50 20100527 15:32:53      248160256 127295488 450139648               1.3215E+10
20100527 13:32:48 20100527 14:32:50       10452992   15646720    4400640               1.5549E+10
20100527 12:32:43 20100527 13:32:48      745693184 948461568 1311620608               2.2789E+10
20100527 11:25:56 20100527 12:32:43     1262026752 1984741376 2358546432               2.7212E+10Basically what I do is I update a 4 million table big redo generated with flashback logs
When I do select after the update I still see the redo generated because of delayed block cleanout but what I also see is the slight increase in flashback data size (check the first row of flashback_database_stat) which suits what you asking for. Select statement generates flashback log
Tested on 11.2.0.1 with single active session on the db
Coskan Gundogar
Blog: http://coskan.wordpress.com
Twitter: http://www.twitter.com/coskan
Linkedin: http://uk.linkedin.com/in/coskan
---------

Oracle 11g :SELECT query blocked..??

Hi Experts,
could you please explain why the below SQL query is blocked?
SELECT 1 FROM DUAL is blocking the SQL statement on GTTAPPUSR@gttccuatcriba04 ( SID=469 ) blocked SQL -> DELETE FROM GTTDB.PURCHASE_ENTRY_ID=:1
SELECT 1 FROM DUAL is blocking the SQL statement on GTTAPPUSR@gttccuatcriba04 ( SID=367 ) blocked SQL -> DELETE FROM GTTDB.PURCHASE_ENTRY_ID=:1
I am scratching my head without any solution when I had a look at the db today. Thanks in advance for your help.
Regards,
Boris
Edited by: user12075620 on Dec 4, 2012 8:58 AM

The SELECT statement is not blocking the UPDATE. As I said in the previous reply, the string that this query produces does not match the logic.
This query is (at least on the surface) correctly identifying that session 1 is blocking session 2. Session 1 holds some lock that session 2 is waiting on. So far, so good. Since session 2 is waiting on the lock, we can easily enough see what session 2 is running (the UPDATE statement). But since session 1 is not blocked, it is potentially off running a ton of other SQL statements (or no SQL statement at all). The query is looking to see what session 1 is running currently. It has no way of determining what session 1 ran at some point in the past to acquire the lock in the first place.
Going back to my KING example,
At noon, session 1 runs
UPDATE emp
SET sal = sal * 2
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SELECT *
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UPDATE emp
SET bonus = 100
WHERE ename = 'KING'Session 2 is blocked. Session 2 is running the UPDATE statement. Session 1 still holds the lock but it is running some completely unrelated SQL statement.
If we run the query you posted, the query will correctly report that session 1 is running the query against the GIANT_VIEW_WITH_LOTS_OF_COMPUTATIONS but incorrectly imply that this SELECT query is the source of the lock. It is not. It simply happens to be the query that the session that does hold the lock happens to be executing at the current moment (why the application seems to be running a lot of queries that select a constant from dual is a separate question).
Justin

Index not being used in Select statement

Friends
I have the following SQL statement:
SELECT
a.acct,
a.date_field,
UPPER(b.feegroup) feegrp,
SUM (a.fee1) fee1,
SUM (a.fee2) fee2,
SUM (a.fee3) fee3
FROM table1 a, table2 b
WHERE 1 = 1
AND a.fee_id = b.fee_id
GROUP BY a.acct, a.date_field, b.feegroup;
Both the tables have index on fee_id column. When I run the explain plan for this statement, I am getting the following output:
Operation | Option | Object Name | Position
SELECT STATEMENT | | | 560299
HASH | GROUP BY| |1
TABLE ACCESS | FULL| table2 | 1
TABLE ACCESS | FULL| table1 | 2
Why Oracle is not using the index?
Edited by: darshilm on Dec 10, 2009 3:56 PM

The proposed plan is the optimal according to your current conditions in the "where clause" where you have only the equality join condition and therefore the CBO can use HASH JOIN. Using any kind of index access would just increase the amount of required work unless you would add some very restrictive conditions which will select rows from relatively small amount of blocks. Here I have to mention that what really counts in the CBO cost calculation is the amount of blocks accessed and not the number of rows. The "currency" for I/O in Oracle is a block and not a row. CBO always uses an assumption that there is nothing in the buffer cache and it will have to perform a physical read for every block.
How many blocks will actually be accessed depends on the data distribution. It can happen that every single row that you have to retrieve resides in a different block and although you access only 1000 rows out of a million row table you would have to visit almost every block of that table. For such a situation a FULL TABLE SCAN is the best access path and Oracle will use multiblock I/O for that. On the other side you can have those 1000 rows only in a few blocks and then the index access would be the most appropriate one. For index access Oracle uses single block I/O. Usually the actual situation is somewhere between this two extreme situations. But you can run some tests by yourself and see when an index access will be replaced by a full table scan while you will make your predicates less selective.
HTH, Joze
Co-author of the forthcoming book "Expert Oracle Practices"
http://www.apress.com/book/view/9781430226680
Oracle related blog: http://joze-senegacnik.blogspot.com/
Blog about flying: http://jsenegacnik.blogspot.com/
Blog about Building Ovens, Baking and Cooking: http://senegacnik.blogspot.com

Select statement works in 8.1.5 but does not work in 8.1.7 why???????

I have written a select statement as part of cursor in a
Database Trigger, the following statement works fine in Oracle
8i ver 8.1.5.0 but the same statement returns error PLS-00103
(Parser related error) in Oracle 8i version 8.1.7.0!!!!!!
The error shown is
PLS-00103Encountered the symbol")" when expecting one of the
following:
from
The Sql statement in a Database Trigger is as follows
select opn_stk,iss_qty,rec_qty,ROWID
from mnth_bal
where to_date(lpad(to_char(month),2,'0')||to_char
(year),'mmyyyy') >= SYSDATE AND
REV_NO = :NEW.REV_NO AND
ITEM_STOCK_ITEM_CD = :NEW.ITEM_CD and
unit_cd = :NEW.unit_cd and
store_cd = :new.store_cd
order by to_date(lpad(to_char(month),2,'0')
||to_char(year),'mmyyyy') ;
Can any one please tell me whats the problem ? In 8.1.5.0 the
same statement in the trigger runs absolutely fine &
compiles.Because of this problem the trigger is not compiling in
8.1.7.0
Would be grateful for any solutions given

Relating line numbers in compile errors to source code.
Oracle does not count blank lines in line numbers. Commenting
with "--" blank lines or deleting blank lines will make the line
counter more accurate.
Oracle counts comments delimited with /*...*/ as one line, no
matter how many lines are in the source code. Using only "--"
will make the line counter more accurate.
Oracle does not count lines before the PL/SQL block DECLARE when
compiling triggers. (CREATE ... TRIGGER....FOR EACH...WHEN(...))
parts of the syntax are not counted. The line in the source
code with the DECLARE of the trigger's PL/SQL block will be line
1.
Hint: Avoid uncertainty. Use "SHO ERR TRIGGER <trigger_name>"
when looking at compile problems.
Good Luck....

Delete Operation in JDBC Sender Adapter not works

Hi,
    I have one student table which contains the fields ID,Name,BirthMonth,BirthYear,ReadFlag fields. ReadFlag is a character field or lenght 1 which contains only values either 'Y' or ' '.
     I want to execute delete operation in this table ie to delete the records which contains the readflag = 'Y'. So, I set the below values for the following parameters.
DELETE FROM student WHERE READFLAG = ' Y '
Query SQL Statement : SELECT * FROM student WHERE readflag = 'Y'
Update SQL Statement : DELETE FROM student WHERE READFLAG = 'Y'
Poll Interval : 60 Seconds.
    There are more records in this table which contains readflag = 'Y'. But, the Adapter does not delete those records from the table i.e delete operation is not executed. At the same time, in Comm. Channel monitoring it does not show any error, but the delete operation is not carried out in the table.
     I tried after 'COMMIT' the table also. But it does not work. What could be the reason ? or How to use Delete Operation effectively on the table ?
     Kindly help me friends to solve this problem.
Thanking you.
Kind Regards,
Jeg.

http://help.sap.com/saphelp_nw04/helpdata/en/7e/5df96381ec72468a00815dd80f8b63/content.htm >>>
<i>Adapter Work Method
You must add an indicator that specifies the processing status of each data record in the adapter (data record processed/data record not processed) to the database table.
The UPDATE statement must alter exactly those data records that have been selected by the SELECT statement. You can ensure this is the case by using an identical WHERE clause. (See Processing Parameters, SQL Statement for Query, and SQL Statement for Update below).
<b>Processing can only be performed correctly when the isolation level for transaction is set to repeatable_read or serializable.
Example
SQL statement for query: SELECT * FROM table WHERE processed = 0;
SQL statement for update: UPDATE table SET processed = 1 WHERE processed = 0;
processed is the indicator in the database.</b></i>
try with repeatable_read or serializable !!!
Also go thru this thread - DELETE Querey in JDBC SENDER

Select Statement Blocking Delete Operation

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