Rewriting a select statement containing a correlated subquery

Hi,
I would like to rewrite the statement below to improve it's performance. Is it possible?
*SELECT DISTINCT A.FIELD1
 ,A.FIELD2
 ,A.FIELD3
 ,A.FIELD4
 ,A.DATE_FIELD1
 ,(SELECT SUM(B.NUMBER_FIELD1)
 FROM TABLE1 B
 where B.FIELD1 = A.FIELD1
 and B.FIELD2 = A.FIELD
 and B.FIELD3 = A.FIELD
 and B.FIELD4 = A.FIELD
 and B.DATE_FIELD1 <= A.DATE_FIELD1
 ) as Total
 FROM TABLE1 A*
The results should be a running total for a given "A.FIELD4" based on the date field "DATE_FIELD".
Many Thanks

Shouldn't the total for 13/JUL/09 be 0 instead of 3100 or am I missing something?
SQL> create table t as
2 select 'CP001' field1, '0004' field2, 'O' field3, '000000000000003' field4, to_date('01/JUL/09', 'dd/mon/yy') date_field1, 1550 number_field1 from dual union all
3 select 'CP001', '0004', 'O', '000000000000003', to_date('01/JUL/09', 'dd/mon/yy'), 1550 from dual union all
4 select 'CP001', '0004', 'O', '000000000000001', to_date('27/FEB/09', 'dd/mon/yy'), 1550 from dual union all
5 select 'CP001', '0004', 'O', '000000000000002', to_date('11/JUN/09', 'dd/mon/yy'), -1550 from dual union all
6 select 'CP001', '0004', 'O', '000000000000003', to_date('13/JUL/09', 'dd/mon/yy'), -1550 from dual union all
7 select 'CP001', '0004', 'O', '000000000000003', to_date('13/JUL/09', 'dd/mon/yy'), 1550 from dual union all
8 select 'CP001', '0004', 'O', '000000000000004', to_date('23/OCT/09', 'dd/mon/yy'), -3100 from dual union all
9 select 'CP001', '0004', 'O', '000000000000005', to_date('26/FEB/10', 'dd/mon/yy'), 1750 from dual union all
10 select 'CP001', '0004', 'O', '000000000000005', to_date('26/FEB/10', 'dd/mon/yy'), 1750 from dual;
Table created.
SQL> select * from t;
FIELD FIEL F FIELD4 DATE_FIELD1 NUMBER_FIELD1
CP001 0004 O 000000000000003 01-07-2009 00:00:00 1550
CP001 0004 O 000000000000003 01-07-2009 00:00:00 1550
CP001 0004 O 000000000000001 27-02-2009 00:00:00 1550
CP001 0004 O 000000000000002 11-06-2009 00:00:00 -1550
CP001 0004 O 000000000000003 13-07-2009 00:00:00 -1550
CP001 0004 O 000000000000003 13-07-2009 00:00:00 1550
CP001 0004 O 000000000000004 23-10-2009 00:00:00 -3100
CP001 0004 O 000000000000005 26-02-2010 00:00:00 1750
CP001 0004 O 000000000000005 26-02-2010 00:00:00 1750
9 rows selected.
SQL> -- your query (added only an extra order by):
SQL> select distinct
2 a.field1
3 , a.field2
4 , a.field3
5 , a.field4
6 , a.date_field1
7 , ( select sum(b.number_field1)
8 from t b
9 where b.field1 = a.field1
10 and b.field2 = a.field2
11 and b.field3 = a.field3
12 and b.field4 = a.field4
13 and b.date_field1 <= a.date_field1
14 ) as total
15 from t a
16 order by a.date_field1;
FIELD FIEL F FIELD4 DATE_FIELD1 TOTAL
CP001 0004 O 000000000000001 27-02-2009 00:00:00 1550
CP001 0004 O 000000000000002 11-06-2009 00:00:00 -1550
CP001 0004 O 000000000000003 01-07-2009 00:00:00 3100
CP001 0004 O 000000000000003 13-07-2009 00:00:00 3100
CP001 0004 O 000000000000004 23-10-2009 00:00:00 -3100
CP001 0004 O 000000000000005 26-02-2010 00:00:00 3500
6 rows selected.
SQL> -- an alternative, without analytics:
SQL> select a.field1
2 , a.field2
3 , a.field3
4 , a.field4
5 , a.date_field1
6 , sum(a.number_field1) total
7 from t a
8 group by a.field1
9 , a.field2
10 , a.field3
11 , a.field4
12 , a.date_field1
13 order by a.date_field1;
FIELD FIEL F FIELD4 DATE_FIELD1 TOTAL
CP001 0004 O 000000000000001 27-02-2009 00:00:00 1550
CP001 0004 O 000000000000002 11-06-2009 00:00:00 -1550
CP001 0004 O 000000000000003 01-07-2009 00:00:00 3100
CP001 0004 O 000000000000003 13-07-2009 00:00:00 0
CP001 0004 O 000000000000004 23-10-2009 00:00:00 -3100
CP001 0004 O 000000000000005 26-02-2010 00:00:00 3500
6 rows selected.

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Always say which version of Oracle you're using.
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Subquery in IN clause of an select statement

Hi friends,
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Edited by: infant_raj on May 28, 2009 12:09 AM

infant_raj wrote:
Hi friends,
The Subquery in IN clause of an select statement take long time , is there any alternate ??
select * from oudata.SURVEY_USER_ANSWERS
where user_id in (select user_id from oudata.SURVEY_USERS where trunc(course_start_date) <'01-Jun-2007');
No database version specified?
No table structures/indexes given?
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Have you got a function based index for "trunc(course_start_date)"?
Why are you not specifying your comparison date as a DATE datatype rather than relying on implicit conversion? i.e. it should be "to_date('01-Jun-2007','DD-MON-YYYY')"
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[How to post a SQL statement tuning request|http://forums.oracle.com/forums/thread.jspa?threadID=863295&tstart=0]
[When your query takes too long...|http://forums.oracle.com/forums/thread.jspa?messageID=1812597#1812597]

Performance of using a Select For Update vs a correlated subquery

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NAME - INACTIVE
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SELECT FIELD FROM ACTIVE_FIELDS WHERE STATUS=ACTIVE
It gives me : Code and Description.
I have then a second table MATERIAL with 3 columns CODE, DESCRIPTION and NAME.
I am looking at doing a query against MATERIAL table as follows
SELECT (SELECT FIELD FROM ACTIVE_FIELDS WHERE STATUS=ACTIVE) from MATERIAL and I expect to only get columns CODE and DESCRIPTION in the result.
If I want to add the NAME field in the result of my query, I just have to change status of NAME field in the eh ACTIVE_FIELDS table..
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that data model looks suspiciously like an attribute-value generic model, thus the need for that funky sql.
read this thread.
Re: SIMPLE Database Design Problem !

Plsql procedure containing select statement to fill page items

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I think I got it:
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;Edited by: wucis on Oct 24, 2011 4:09 PM

SELECT statement comparing 2 fields in a table.

Hi,
Can someone help me out in making a efficient SELECT statement for the follwing requirement.
Say, I want to select all the records from a database table where the field, PLANT is equal to field SALESORG in the table (i.e., when both fields are equal select that record).
Thanks & regards,
Sree

Hello,
I think this is the answer to your question... if you explain a bit more we can formulate a query.
Subquery
Variants:
1. ( select )
2. ALL ( select )
3. ANY ( select )
4. SOME ( select )
Effect
A subquery is a SELECT statement select that occurs within a
SELECT,
OPEN CURSOR,
UPDATE, or
DELETE statement
in the WHERE clause or HAVING clause, to check whether data from database tables or views meets certain criteria.
Subqueries have a restricted syntax in comparison to the normal SELECT statement:
SELECT result FROM source [WHERE where] [GROUP BY fields] [HAVING having].
Variant 1
( select )
If the subquery returns a single value, you can use any relational operator except LIKE and BETWEEN.
Example
Selecting the flights with the most passengers:
DATA: WA TYPE SFLIGHT.
SELECT * FROM SFLIGHT
 INTO WA
 WHERE SEATSOCC = ( SELECT MAX( SEATSOCC ) FROM SFLIGHT ).
WRITE: / WA-CARRID, WA-CONNID, WA-FLDATE.
ENDSELECT.
Note
If you use a subquery with a relational operator instead of EXISTS, you may only specify one column in the SELECT clause. This can be either a field from the database table or an aggregate expression. Subqueries of this kind are referred to as scalar subqueries.
Variant 2
ALL ( select )
If the subquery returns several lines, each containing one value, you specify that the comparison should apply for all of the values it returns.
Example
This example shows how to use ALL. It displays a list of the customer IDs of the customer (or customers) who have made the most bookings:
DATA: ID TYPE SBOOK-CUSTOMID, CNT TYPE I.
SELECT CUSTOMID COUNT( * ) AS C FROM SBOOK
 INTO (ID, CNT)
 GROUP BY CUSTOMID
 HAVING COUNT( * ) >=
 ALL ( SELECT COUNT( * ) FROM SBOOK GROUP BY CUSTOMID ).
WRITE: / ID, CNT.
ENDSELECT.
Variant 3
ANY ( select )
Variant 4
SOME ( select )
If the subquery returns several lines each containing one value, this variant specifies that the comparison should apply to at least one of the values returned. The IN operator is the same as the combination = ANY.
&ABAP_HINT
If you use a subquery with the EXISTS operator, the expression is true if the subquery selects at least one line. You can useuse * in the SELECT clause of subqueries that use EXISTS.
Example
Selecting all flights from Frankfurt to New York between 1.1.1999 and 31.3.1999 that are not yet full:
DATA: WA_SFLIGHT TYPE SFLIGHT.
SELECT * FROM SFLIGHT AS F INTO WA_SFLIGHT
 WHERE SEATSOCC < F~SEATSMAX
 AND EXISTS ( SELECT * FROM SPFLI
 WHERE CARRID = F~CARRID
 AND CONNID = F~CONNID
 AND CITYFROM = 'FRANKFURT'
 AND CITYTO = 'NEW YORK' )
 AND FLDATE BETWEEN '19990101' AND '19990331'.
WRITE: / WA_SFLIGHT-CARRID, WA_SFLIGHT-CONNID,
 WA_SFLIGHT-FLDATE.
ENDSELECT.
Subqueries such as the one in this example, in which the WHERE clause uses fields from the main query, are known as correlated subqueries. Subqueries can be nested, and a given subquery may contain any fields from other, hierarchically-superior subqueries.
In a correlated subquery, the subquery is executed for each line r returned by the main query. In the above example, the main query finds all flights in table SFLIGHT that are not full and that have a date that meets the selection criterion. The statement then performs the subquery for each of the records returned by the main query, using the corresponding values of CARRID and CONNID, to check whether the relevant flight operates between Frankfurt and New York.
Additional help
Subqueries

JDOQL Correlated Subquery - Bad SQL

Hi,
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For the record, this is in part due to a bug in Kodo's SQL92 joining.
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Paul Mogren wrote:
Certainly... Here's a simple example using Microsoft's JDBC Driver for SQL
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pm.newQuery(Container.class,
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[params=(int) 1]} [code=156, state=HY000]
Patrick Linskey wrote:
Hi Paul,
Kodo's correlated subquery support does have some known limitations. Can
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-Patrick
Paul Mogren wrote:
Hi,
When I execute a JDOQL correlated subquery, the generated SQL is either
invalid or incorrect. Exactly what happens depends on the exact query, and
on the target database type, but I believe it all stems from the same
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If you need further details to reproduce this, please let me know. I'll be
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am depending on this functionality. I have a test application to
demonstrate the problem.
I'm using Kodo 3.3.3 and application identity.
Paul Mogren
CommerceHub

Top n Analysis using correlated subquery

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Select distinct a.sal
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Thanks in advance

Try breaking the query down and rewriting it in order to follow the logic;
SQL> --
SQL> -- Start by getting each salary from emp along with a count of all salaries in emp
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 3000 12
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 2850 12
 2450 12
 1600 12
 1500 12
 1300 12
 1250 12
 1250 12
 1100 12
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 800 12
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SQL> --Add a condition to the count for only salaries below or equal to the current salarySQL> --
SQL> select a.sal,
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SQL> -- Add a condition to only pick the nth highest salary
SQL> --
SQL> select a.sal,
 (select count (distinct b.sal) from scott.emp b where a.sal <=b.sal) rank_sal
from scott.emp a
where (select count (distinct b.sal) from scott.emp b where a.sal <=b.sal) = 4
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 2850 4
1 row selected.Hope this helps.

SQL Bug in "Minus" in correlated subquery presence of index (11.2.0.1.0)

SQL Bug in "Minus" in correlated subquery presence of index
(Oracle Database 11g Release 11.2.0.1.0)
Below, there is a small example that shows the bug. Further below,
there are some more comments.
drop table Country;
create table Country
(code VARCHAR2(4) constraint countrykey PRIMARY KEY,
name VARCHAR2(35));
-- if the key constraint is not given, the bug does not occur
drop table City;
create table City
(name VARCHAR2(35),
country VARCHAR2(4),
population number);
drop table Locatedon;
create table Locatedon
(city VARCHAR2(35),
country VARCHAR2(4),
island VARCHAR2(35));
insert into country values('E','Spain');
insert into country values('F','France');
insert into country values('S','Sweden');
insert into country values('GB','Sweden');
insert into city values('Ajaccio','F',53500);
insert into city values('Paris','F',2152423);
insert into city values('Palma','E',322008);
insert into city values('Madrid','E',3041101);
insert into city values('Stockholm','S',711119);
insert into city values('London','GB',6967500);
insert into locatedon values('Ajaccio','F','Corse');
insert into locatedon values('Palma','E','Mallorca');
insert into locatedon values('London','GB','Great Britain');
-- all countries that have a city that is not located on
-- some island: should be E, F, S.
Select c.name
From country c
Where exists
((Select name
From city
Where city.country=c.code)
minus
(Select city
From locatedon
Where locatedon.country=c.code)
-- wrong answer: only Sweden; Spain and France not in the answer!
select distinct country from
((Select name, country
From city)
minus
(Select city, country
From locatedon)
-- correct answer: E, F, S
Comments:
The bug has been found by students in our SQL course.
Using a larger database from that course, the bug can be reproduced
(same queries as above) at
http://www.semwebtech.org/sqlfrontend/
(wrong: 142 answers, correct: 154 answers)
During reducing it to a simple sample, there were some interesting
observations: trying with smaller and simpler tables (without the keys)
and synthetic data, the bug did not occur immediately. When
restating the query after about one day, the bug occurred. Obviously,
Oracle creates some index on its own in course of its internal
optimization that (or more exactly, its usage) exhibits the bug. The
query plan (showed in SQL Developer) was the same before and after.
Wolfgang

There's a typo in the test data - GB should presumably not be in Sweden. However....
the bug did not occur immediatelyIt's possible. But what would have almost certainly happened is that the execution plan DID change at some point. There are various reasons why it might not be immediate.
Obviously, Oracle creates some index on its own in course of its internal optimizationFar from obvious, what are you on about?
The query plan was the same before and afterBet you it wasn't.
A clear illustration of the issue and indication that it must be a bug is below.
Simply by hinting a different access method, we can change the result. Therefore, bug.
See [url http://support.oracle.com]Oracle Support and search for "wrong results".
Please raise with Oracle Support to get confirmation of bug.
There have been so many wrong results bugs recently, it's getting ridiculous.
It's a real issue, IMHO.
If you can't trust the DB to get your data right....
Note that the query plan is very much NOT the same and it is the difference in query plan which s that is the root cause of the bug.
SQL> select * from v$version;
BANNER
Oracle Database 11g Enterprise Edition Release 11.2.0.2.0 - 64bit Production
PL/SQL Release 11.2.0.2.0 - Production
CORE    11.2.0.2.0      Production
TNS for Linux: Version 11.2.0.2.0 - Production
NLSRTL Version 11.2.0.2.0 - Production
SQL> SELECT c.name
2 FROM   country1 c
3 WHERE exists ((SELECT name
4                  FROM   city1
5                  WHERE city1.country=c.code)
6                  MINUS
7                 (SELECT city
8                  FROM   locatedon1
9                  WHERE locatedon1.country=c.code));
NAME
Sweden
SQL> SELECT /*+ full(c) */
2         c.name
3 FROM   country1 c
4 WHERE exists ((SELECT name
5                  FROM   city1
6                  WHERE city1.country=c.code)
7                  MINUS
8                 (SELECT city
9                  FROM   locatedon1
10                  WHERE locatedon1.country=c.code));
NAME
Spain
France
Sweden
SQL> explain plan for
2 SELECT c.name
3 FROM   country1 c
4 WHERE exists ((SELECT name
5                  FROM   city1
6                  WHERE city1.country=c.code)
7                  MINUS
8                 (SELECT city
9                  FROM   locatedon1
10                  WHERE locatedon1.country=c.code));
Explained.
SQL> select * from table(dbms_xplan.display);
PLAN_TABLE_OUTPUT
Plan hash value: 156929629
| Id | Operation                    | Name       | Rows | Bytes | Cost (%CPU)| Time     |
|   0 | SELECT STATEMENT             |            |     1 |    27 |    12 (25)| 00:00:01 |
|   1 | NESTED LOOPS                |            |       |       |            |          |
|   2 |   NESTED LOOPS               |            |     1 |    27 |    12 (25)| 00:00:01 |
|   3 |    VIEW                      | VW_SQ_1    |     6 |    24 |    10 (20)| 00:00:01 |
|   4 |     MINUS                    |            |       |       |            |          |
|   5 |      SORT UNIQUE             |            |     6 |   138 |            |          |
|   6 |       TABLE ACCESS FULL      | CITY1      |     6 |   138 |     4   (0)| 00:00:01 |
|   7 |      SORT UNIQUE             |            |     3 |    69 |            |          |
|   8 |       TABLE ACCESS FULL      | LOCATEDON1 |     3 |    69 |     4   (0)| 00:00:01 |
|* 9 |    INDEX UNIQUE SCAN         | COUNTRYKEY |     1 |       |     0   (0)| 00:00:01 |
| 10 |   TABLE ACCESS BY INDEX ROWID| COUNTRY1   |     1 |    23 |     1   (0)| 00:00:01 |
Predicate Information (identified by operation id):
   9 - access("VW_COL_1"="C"."CODE")
Note
   - dynamic sampling used for this statement (level=4)
26 rows selected.
SQL> explain plan for
2 SELECT /*+ full(c) */
3         c.name
4 FROM   country1 c
5 WHERE exists ((SELECT name
6                  FROM   city1
7                  WHERE city1.country=c.code)
8                  MINUS
9                 (SELECT city
10                  FROM   locatedon1
11                  WHERE locatedon1.country=c.code));
Explained.
SQL> select * from table(dbms_xplan.display);
PLAN_TABLE_OUTPUT
Plan hash value: 1378726376
| Id | Operation            | Name       | Rows | Bytes | Cost (%CPU)| Time     |
|   0 | SELECT STATEMENT     |            |     1 |    23 |    14 (15)| 00:00:01 |
|* 1 | FILTER              |            |       |       |            |          |
|   2 |   TABLE ACCESS FULL | COUNTRY1   |     4 |    92 |     4   (0)| 00:00:01 |
|   3 |   MINUS              |            |       |       |            |          |
|   4 |    SORT UNIQUE       |            |     1 |    23 |     5 (20)| 00:00:01 |
|* 5 |     TABLE ACCESS FULL| CITY1      |     1 |    23 |     4   (0)| 00:00:01 |
|   6 |    SORT UNIQUE       |            |     1 |    23 |     5 (20)| 00:00:01 |
|* 7 |     TABLE ACCESS FULL| LOCATEDON1 |     1 |    23 |     4   (0)| 00:00:01 |
Predicate Information (identified by operation id):
   1 - filter( EXISTS ( (SELECT "NAME" FROM "CITY1" "CITY1" WHERE
              "CITY1"."COUNTRY"=:B1)MINUS (SELECT "CITY" FROM "LOCATEDON1" "LOCATEDON1"
              WHERE "LOCATEDON1"."COUNTRY"=:B2)))
   5 - filter("CITY1"."COUNTRY"=:B1)
   7 - filter("LOCATEDON1"."COUNTRY"=:B1)
Note
   - dynamic sampling used for this statement (level=4)
27 rows selected.Just to show that it's related to query transformation:
SQL> SELECT /*+
2             no_query_transformation
3         */
4         c.name
5 FROM   country1 c
6 WHERE exists ((SELECT name
7                  FROM   city1
8                  WHERE city1.country=c.code)
9                  MINUS
10                 (SELECT city
11                  FROM   locatedon1
12                  WHERE locatedon1.country=c.code));
NAME
Spain
France
Sweden
SQL> Edited by: Dom Brooks on Jun 30, 2011 2:50 PM

Rewriting a select statement containing a correlated subquery

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