Select count(*) on sql statement returning zero when a matching row exists.

Our account has an ANSI C application that checks for the existence a row on an Oracle table(s) by using the following SQL:
int iCount = 0;
EXEC SQL
SELECT count(rownum) INTO :iCount
FROM sys.all_tab_columns
WHERE table_name IN
(SELECT table_name FROM
sys.all_synonyms
WHERE upper(synonym_name) = upper(:szDestTable))
AND upper(column_name) = upper(:szColumnName)
AND owner = 'DBAUSER';
The bind variables szDestTable and szColumnName are populated with values parsed from columns on another database table. This application is executed through out the day. Occasionally, the application will report a zero in the iCount when there should be a match. I have verified the szDestTable and szColumnName are populated with the correct values which would find a match and they are correct. To make matters even stranger, the application will parse the same input values and find a match (as it should). At some point during the day, and it can be at any time, the application will NOT find a match on the same file, same values. Every subsequent execution of this application will not find a match on the same values. Once the database is brought down and started up in the evening for its normal backups, the application will find a match again on the same values. This problem does not occur every day. I could be a week or a week and a half between incidents.
I printed the contents of the sqlca.sqqlerrm.sqlerrmc field to a log file. The sqlca.sqlerrm.sqlerrmc field reported an ORA-1405 bind variable was null when the iCount was reporting a zero. When I compiled this application, I set the Proc*C flag to UNSAFE_NULLS=yes since there are other bind variable in the application that can be NULL and that is ok.
The above SQL is compiled into the C application using the Proc*C compiler. It is compiled using the Oracle 11.2.0.2 libraries. The application is executed against an Oracle 11.2.0.2 database. The database and application are executed on an HP/Unix 11.31 platform.
This problem did not start occurring until our account went from Oracle 10.2 to Oracle 11.2. Recently, I have changed the SQL to perform a “SELECT COUNT(rownum)” instead of the “SELECT COUNT(*)”. I compiled the application and executed the new application with the SELECT COUNT(rownum) against the same database where the same application with the SELECT COUNT(*) was failing to find a row that actually existed. The application with the SELECT COUNT(rownum) found the matching row as it should have. The new application has been executing in production for about 10 days now without any problems against ten various Oracle 11.2 databases.
Why would SELECT COUNT(*) and SELECT COUNT(rownum) be any different?

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Select Count(*) from... returns zero, select * from... returns 4000 recs?

Hi,
I have an odd situation where "select count(*) from my_view where some_clause" returns 0, but the exact same query fetching the data (ie "select * from my_view where some_clause") works fine and fetches, correctly, 4000+ records.
I have tried dropping and recreating the view, and collecting DB stats again, but the problem persists.
I had a look at the explain plans and they are very different, but both the SQL statements work fine on a copy of the database taken with impdp.
Does anyone have any suggestions on what might be going on here ?
Any help would be appreciated, I've run out of ideas !
Dave
Edited by: user10281551 on 18-Sep-2008 00:43
Edited by: user10281551 on 18-Sep-2008 00:44

Maybe it's the bug that a function based index is present and gets incorrectly used in the select count(*) statement?
If that's not the case, then please show us more details, like the statement and both execution plans.
Regards,
Rob.

SQL statement returning boolean?

Following a guide for querying Oracle databases in java and it suggests using this code to connect and get some select results:
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Looking at the API
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Hi,
I'm trying to create a very simple stored procedure, but having never worked with them before I'm not quite sure what I'm doing wrong.
Here's my code:
create or replace
procedure contact_return(
    v_contact_id IN varchar2,
    p_cursor OUT SYS_REFCURSOR)
AS
begin
set sql_statement varchar2(4000) := '
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if v_contact_id is not null then
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end if;
open p_cursor for sql_statement;
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It's actually returning 2 errors:
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Thanks

rajendra wrote:
Dear User,
It is not allowed to declare a variable inside the PL/SQL block means after begin ( in your case line no 7 ).
Lot of errors in your code.
Tell me your exact requirement and what you want to do , after that I will be able to solve your problem.
Thanks,
Rajendra
Well, you can declare after the begin, though it'll be as part of an embedded code block e.g.
SQL> ed
Wrote file afiedt.buf
1 create or replace procedure contact_return(empno IN number
2                                            ,c     OUT SYS_REFCURSOR
3                                            ) AS
4 begin
5    declare
6      sql_statement varchar2(4000) := '
7        select *
8        from emp
9        where empno = nvl(:1,empno)';
10    begin
11      open c for sql_statement using contact_return.empno;
12    end;
13* end;
SQL> /
Procedure created.
SQL> var x refcursor
SQL> exec contact_return(7788,:x);
PL/SQL procedure successfully completed.
SQL> print x;
     EMPNO ENAME      JOB              MGR HIREDATE                    SAL       COMM     DEPTNO
      7788 SCOTT      ANALYST         7566 19-APR-1987 00:00:00       3000                    20
so, it is allowed, as long as it's coded correctly.

Sub selects in a SQL statement

Hi, I have a query with an obsene amount of sub selects,
for example :
SELECT p.ID,
(select something from data where id = p.id) data1,
(select somelse from data2 where id = p.id) data2,
(select someelse from data3 where id = p.id) data3,
(select someelse from data4 where id = p.id) data4,
(select someelse from data5 where id = p.id) data5,
FROM property P
WHERE ..........
this query is taking a long time to process. Is there a more efficient way of doing such a statement?
thanks in advance

Gabe:
Since the original poster said "this query is taking a long time to process", I assumed that there was a one-to-one relationship between properties and each of the dataX tables, otherwise, as you pointed out, he would be complaining about ORA-01427: single-row subquery returns more than one row
In my union, I am returning a single column from each of the data tables (plus the id), and a NULL for each of the other columns in the in-line view. The MAX function just gets the single row for each column that actually has a value.
As a test case, I did:
CREATE TABLE properties AS
SELECT rownum id, object_name
FROM all_objects
WHERE rownum < 11;
CREATE TABLE data1 (id NUMBER, descr VARCHAR2(10));
INSERT INTO data1 VALUES(1, 'ONE');
INSERT INTO data1 VALUES(2, 'TWO');
INSERT INTO data1 VALUES(3, 'THREE');
CREATE TABLE data2 (id NUMBER, descr VARCHAR2(10));
INSERT INTO data2 VALUES(4, 'FOUR');
INSERT INTO data2 VALUES(5, 'FIVE');
INSERT INTO data2 VALUES(6, 'SIX');
CREATE TABLE data3 (id NUMBER, descr VARCHAR2(10));
INSERT INTO data3 VALUES(7, 'SEVEN');
INSERT INTO data3 VALUES(8, 'EIGHT');
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SQL> SELECT p.id, p.object_name,
2         (SELECT descr FROM data1 WHERE id = p.id) data1,
3         (SELECT descr FROM data2 WHERE id = p.id) data2,
4         (SELECT descr FROM data3 WHERE id = p.id) data3
5 FROM properties p
6 ORDER BY p.id;
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         1 TAB$                           ONE
         2 I_IND1                         TWO
         3 I_COBJ#                        THREE
         4 USER$                                     FOUR
         5 I_OBJ1                                    FIVE
         6 I_PROXY_ROLE_DATA$_2                      SIX
         7 BOOTSTRAP$                                           SEVEN
         8 I_ICOL1                                              EIGHT
         9 UNDO$                                                NINE
        10 PROXY_ROLE_DATA$
10 rows selected.
Statistics
          0 recursive calls
          0 db block gets
         93 consistent gets
          0 physical reads
          0 redo size
       1000 bytes sent via SQL*Net to client
        655 bytes received via SQL*Net from client
          2 SQL*Net roundtrips to/from client
          1 sorts (memory)
          0 sorts (disk)
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My query returns:
SQL> SELECT p.id, p.object_name, a.data1, a.data2, a.data3
2 FROM properties p,
3       (SELECT id, MAX(data1) data1, MAX(data2) data2, MAX(data3) data3
4        FROM (SELECT id, descr data1, TO_CHAR(NULL) data2, TO_CHAR(NULL) data3
5              FROM data1
6              UNION ALL
7              SELECT id, TO_CHAR(NULL), descr, TO_CHAR(NULL)
8              FROM data2
9              UNION ALL
10              SELECT id, TO_CHAR(NULL), TO_CHAR(NULL), descr
11              FROM data3)
12        GROUP BY id) a
13 WHERE p.id = a.id(+)
14 ORDER BY p.id;
        ID OBJECT_NAME                    DATA1      DATA2      DATA3
         1 TAB$                           ONE
         2 I_IND1                         TWO
         3 I_COBJ#                        THREE
         4 USER$                                     FOUR
         5 I_OBJ1                                    FIVE
         6 I_PROXY_ROLE_DATA$_2                      SIX
         7 BOOTSTRAP$                                           SEVEN
         8 I_ICOL1                                              EIGHT
         9 UNDO$                                                NINE
        10 PROXY_ROLE_DATA$
10 rows selected.
Statistics
          0 recursive calls
          0 db block gets
         12 consistent gets
          0 physical reads
          0 redo size
       1000 bytes sent via SQL*Net to client
        655 bytes received via SQL*Net from client
          2 SQL*Net roundtrips to/from client
          2 sorts (memory)
          0 sorts (disk)
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SQL> SELECT p.id, p.object_name, d1.descr data1, d2.descr data2, d3.descr data3
2 FROM properties p, data1 d1, data2 d2, data3 d3
3 WHERE p.id = d1.id(+) AND
4        p.id = d2.id(+) AND
5        p.id = d3.id(+)
6 ORDER BY p.id;
        ID OBJECT_NAME                    DATA1      DATA2      DATA3
         1 TAB$                           ONE
         2 I_IND1                         TWO
         3 I_COBJ#                        THREE
         4 USER$                                     FOUR
         5 I_OBJ1                                    FIVE
         6 I_PROXY_ROLE_DATA$_2                      SIX
         7 BOOTSTRAP$                                           SEVEN
         8 I_ICOL1                                              EIGHT
         9 UNDO$                                                NINE
        10 PROXY_ROLE_DATA$
10 rows selected.
Statistics
          0 recursive calls
          0 db block gets
         12 consistent gets
          0 physical reads
          0 redo size
       1000 bytes sent via SQL*Net to client
        655 bytes received via SQL*Net from client
          2 SQL*Net roundtrips to/from client
          1 sorts (memory)
          0 sorts (disk)
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HTH
John

Two count(*) in sql statement

hi viewers,
I need the similar query in oracle for the following Informix query.
select count(*),(select count(*) from table_name where col1=10) from table_name where col1=10;
i have a solution also but the problem is, if that table has no rows then output is not 0,0
select count(*),(select count(*) from table_name where col1=10) from table_name where col1=10 group by col1;
thanks
hari

A little remark: the behavoiur you stick on is a default feature in Oracle:
SQL> select count(*) from emp where deptno = 40;
COUNT(*)
0
SQL> select count(*) from emp where deptno = 40 group by deptno;
no rows selectedThese two queries work differ. It is described in Oracle documentation:
http://download.oracle.com/docs/cd/B19306_01/server.102/b14200/functions001.htm#i89203
Oracle applies the aggregate functions to each group of rows and returns a single result row for each group.
If you omit the GROUP BY clause, then Oracle applies aggregate functions in the select list to all the rows in the queried table or view
As Alex pointed out, you should not include group by clause and should use count(*) instead of a subquery.
Rgds.

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select owner, tablename, sysdate
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dba_tables.num_row is not an option because I am not running
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But I am not sure how.
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JOHN EMP 433 12-JAN-01
JOHN EMP 476 12-JAN-01
MARGE LOC 198 13-JAN-01
All help is very much appreciated,
Mike

HI guy's !
Thanx for all the suggestions, I have tried them all out and its
almost there. However your suggestions display the output on the
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but this doesnt seem to work. I am sorry that I do not know
pl/sql. Can anyone assist me in completing the code with an
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Suresh: Your code works, but as mentioned above I would like to
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table. Therefore, I cannot query the history of the number of
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Again; thanx all for your suggestions! Now I just need a final
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Mike

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Why would that be if I can execute the sql statement that is being used in the OLEDB Source, and I get a result, yet the destination gets no rows afterwards. Even executing the Dataflow task by itself, no rows are written.
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I have been using the .NET Framework Data Provider for Oracle and have run into the following limitation.
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1. With ODP.NET, you can batch your SQL statements using anonymous PL/SQL block. For example,
begin
open :1 for select * from emp;
open :2 for select * from dept;
open :3 for select col1 from test;
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How to put the SQL-statement returned value into the field (as a default)

Hi,
I am using Developer/2000 (Forms Designer) under windows 98.
Please tell me how to put the SQL-statement value (as a default value) into the field before enter-query mode. Noted that I have tried the following ways but still some problems:-
1) Place the SQL-statement into PRE_QUERY trigger in the form/block level.
There is a message box which ask 'Do you want to save the changes?'.
2) Place the SQL-statement before execute enter_query. There is still a
message box which ask 'Do you want to save the changes?'.
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solved it!
1) Suppress DEFAULT save message
if form_failure then
raise form_trigger_failure;
end if;
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Ref: Title='Default value in query field in ENTER_QUERY mode' in designer forum by CVZ
form level trigger
============
WHEN-NEW-ITEM-INSTANCE
=======================
if :system.mode = 'ENTER-QUERY' then
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Help Using Count and SQL statements

Hello
This problem has been bugging me incesantly and I would be reaaaaaaally grateful if someone could help here
I want to create query that woud count the number of times a certain unedited word would be matched against different edited words
This query works well in MS ACCess but not in java
query =" SELECT Count(*) AS WordCount, Segmentations.EditedWord FROM [select Segmentations.EditedWord FROM Segmentations where Segmentations.UneditedWord = '"+Word+"']. AS c GROUP BY Segmentations.EditedWord";
I've tried removing the Segmentations. and changing it to
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But still nothing
I think that is due to the fact that you can't call Count(*) and another field at the same time
pleas eif anyone knows a way around this send it ASAP
thanx

Why not use,
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HTH

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select a.segment3, b.descr, b.leader, sum(a.period_activity_a) from payman.snp_op_detail a,
hrman.organisation_t b
where a.segment3 = b.org_member_id and
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a.segment2 between 5400 and 8999 and
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4001     CLOSED: RF-CASSAVA MOSAIC DIS.      S.SHOLOLA     0
4001     CLOSED: RF-CASSAVA MOSAIC DIS.           0
4001               0
4005     Closed: BELG. STRAT MUSA-ESARC      S.SHOLOLA     0
4005     Closed: BELG. STRAT MUSA-ESARC           0
4005               0
4006     Closed: BELG. STRATEG MUSA KUL      S.SHOLOLA     0
4006     Closed: BELG. STRATEG MUSA KUL           0
4006               0
4007     Closed: BELG STRATEG MUSA ONNE     S.SHOLOLA     0
4007     Closed: BELG STRATEG MUSA ONNE          0
4007               0
4009     Closed: EEC-OFAR II REIMB EXPs      S.SHOLOLA     0
4009     Closed: EEC-OFAR II REIMB EXPs           0
4009               0
Edited by: OlaTunde on 19-Jan-2012 04:41

Hi,
OlaTunde wrote:
I want to select columns and total only not subtotal. the only thing I can think about is rollup. but rollup brings rollup for each column. how can I get total without repeating the rows?Sorry, it's unclear what you want. Whenever you have a problem, post a little sample data (CREATE TABLE and INSERT statements) and the results you want from that data. Explain how you get those results from that data.
If you can show your problem using commonly available tables (such as scott.emp) then you don't need to post any sample data; just the results and the explanation.
Always say which version of Oracle you're using.
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Analytic functions can produce the same total as aggregate functions, without changing the number of rows at all.
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It all depends on your data, what you want from that data, and your version. If you're willing to share what you know about those things, other people will share what they know about SQL.

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hi,
got a problem when using 'lag' in a view.
if i set up a select statement using 'lag' and execute it, all the results are correct.
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has anyone experienced this ?
any hints would be good.
thanks
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using Oracle 10g Express
version 10.2.0.1.0
can not download the patch because i can not log into metalink - no CSI
setting to resolved.
Message was edited by:
user614086

Hi again,
I think the problem is more with your expectation of what LAG should be doing than with LAG itself.
LAG must calculate based on the result set, in your stand alone query that means what's left after the WHERE clause is applied.
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insert into test_lag values (1, 'ONE', trunc(sysdate,'DD') - 1);
insert into test_lag values (2, 'TWO' trunc(sysdate,'DD') );
insert into test_lag values (3, 'THREE', trunc(sysdate,'DD') + 1);
insert into test_lag values (4, 'FOUR', trunc(sysdate,'DD') + 2);
commit;
create or replace view test_lag_v
as
select column1, column2, lag(column2, 1) over (order by column1 asc) AS laggery, lag(column1) over (order by column3 desc) as laggery_2
from test_lag;
ME_XE?select *
2 from test_lag_v
3 where column1 <> 3;
           COLUMN1 COLUMN2                        LAGGERY                                 LAGGERY_2
                 4 FOUR                           THREE
                 1 ONE                                                                            3
2 rows selected.
Elapsed: 00:00:00.50
ME_XE?
ME_XE?select *
2 from test_lag_v;
           COLUMN1 COLUMN2                        LAGGERY                                 LAGGERY_2
                 4 FOUR                           THREE
                 3 THREE                          ONE                                             4
                 1 ONE                                                                            3
3 rows selected.
Elapsed: 00:00:00.68

How to always hide the SQL statements for users when they run User Queries?

Hi,
from the IT dept. position, I don't want users to see and be so curious about the SQL commands.
How can I always hide the textbox of Display Query Structure?
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Hi,
Unfortunately system design has short of this function. If users are allowed to run those queries, you can not hide the query structure.
You may post a DRQ here: /community [original link is broken]
Thanks,
Gordon

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I have included the code I am using below and would appreciate any help.
Best Regards,
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import java.sql.*;
import java.math.*;
import oracle.xml.sql.query.*;
import oracle.xml.sql.docgen.*;
import oracle.jdbc.*;
import oracle.jdbc.driver.*;
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// create an OracleXMLDocGen object of their own.
OracleXMLDocGen doc = (OracleXMLDocGen) new OracleXMLDocGenString();
for (int rowCnt = 1; rowCnt < 8000; rowCnt = rowCnt + 1000)
// get the xml
System.out.println("Before skip rowCnt:"+rowCnt);
qry.setSkipRows(rowCnt); // process next batch
System.out.println("Before getXML");
// this is where I get the exception on the second iteration of the loop
qry.getXML(doc);
System.out.println("Displaying document");
// System.out.println(doc.getXMLDocumentString());
System.out.println("Row number:"+rowCnt);
System.out.flush();
System.out.println("End of document");
qry.close();
null

I used qry.getXMLString()
But called it for every row, ie, set
qry.maxRows(1) and qry.skipRows(rowcount-1).
The down side is I had to postprocess the String to remove the processing instruction and doc level tags.

Select count(*) on sql statement returning zero when a matching row exists.

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