Associative Arrays, Indexes vs. Full Table Scans

Hello,
I just started using ODP.Net to connect my .Net Web Service to our Oracle Database. The reason why I switched to ODP.Net is support for arrays. If I wanted to pass in arrays to the procedure I had to pass it in through a varchar2 in a CSV formatted string.
ex. "123,456,789"
So now I'm using ODP.net, passing in PL/SQL Associative Arrays then converting those arrays to nested tables to use within queries.
ex.
OPEN OUT_CURSOR FOR
SELECT COLUMN1, COLUMN2
WHERE COLUMN_ID IN (SELECT ID FROM TABLE(CAST(ASSOC_ARR_TO_NESTED(IN_ASSOC_ARR) AS NESTED_TBL_TYPE)))
It uses the array successfully however what it doesn't do is use the index on the table. Running the same query without arrays uses the index.
My colleague who works more on the Oracle side has posted this issue in the database general section (link below). I'm posting here because it does seem that it is tied to ODP.Net.
performance - index not used when call from service
Has anyone ever experienced this before?

You have to use a cardinality hint to force Oracle to use the index:
/*+ cardinality(tab 10) */See How to use OracleParameter whith the IN Operator of select statement

Similar Messages

Why does not a query go by index but FULL TABLE SCAN

I have two tables;
table 1 has 1400 rwos and more than 30 columns , one of them is named as 'site_code' , a index was created on this column;
table 2 has more 150 rows than 20 column , this primary key is 'site_code' also.
the two tables were analysed by dbms_stats.gather_table()...
when I run the explain for the 2 sqls below:
select * from table1 where site_code='XXXXXXXXXX';
select * from table1 where site_code='XXXXXXXXXX';
certainly the oracle explain report show that 'Index scan'
but the problem raised that
I try to explain the sql
select *
from table1,table2
where 1.'site_code'=2.'site_code'
the explain report that :
select .....
FULL Table1 Scan
FULL Table2 Scan
why......

Nikolay Ivankin wrote:
BluShadow wrote:
Nikolay Ivankin wrote:
Try to use hint, but I really doubt it will be faster.No, using hints should only be advised when investigating an issue, not recommended for production code, as it assumes that, as a developer, you know better than the Oracle Optimizer how the data is distributed in the data files, and how the data is going to grow and change over time, and how best to access that data for performance etc.Yes, you are absolutly right. But aren't we performing such an investigation, are we? ;-)The way you wrote it, made it sound that a hint would be the solution, not just something for investigation.
select * from .. always performs full scan, so limit your query.No, select * will not always perform a full scan, that's just selecting all the columns.
A select without a where clause or that has a where clause that has low selectivity will result in full table scans.But this is what I have ment.But not what you said.

Function based indexes doing full table scan

Guys,
I am testing function based indexes and whatever I do
it is doing a full table scan.
1)I have set the following init parameters as
QUERY_REWRITE_ENABLED=TRUE
QUERY_REWRITE_INTEGRITY=TRUSTED
2)CREATE INDEX i3 ON emp(UPPER(ename));
3) ANALYZE TABLE emp COMPUTE STATISTICS
ANALYZE INDEX I3 COMPUTE STATISTICS
4) DELETE plan_table;
5) EXPLAIN PLAN SET statement_id='Test1' FOR
SELECT ename FROM emp WHERE UPPER(ename) = 'KING';
6) SELECT LPAD(' ',2*level-2)||operation||' '||options||' '||object_name
query_plan
FROM plan_table
WHERE statement_id='Test1'
CONNECT BY prior id = parent_id
START WITH id = 0 order by id
7) And the query plan shows as
SELECT STATEMENT
TABLE ACCESS FULL EMP
I am using 9.0.1.4 !!!
Any help is appreciated !!!
Regards,
A.Kishore

One of the many new features in Oracle 8i is the Function-Based Index (we will refrain from using FBI, but only just). This allows the DBA to create indexes on functions or expressions; these functions can be user generated pl/sql functions, standard SQL functions (non-aggregate only) or even a C callout.
A classic problem the DBA faces in SQL Tuning is how to tune those queries that use function calls in the where clause, and result in indexes created on these columns not to be used.
Example
Standard B-Tree index on SURNAME with cost based optimizer
create index non_fbi on sale_contacts (surname);
analyze index non_fbi compute statistics;
analyze table sale_contacts compute statistics;
SELECT count(*) FROM sale_contacts
WHERE UPPER(surname) = 'ELLISON';
Execution Plan
0 SELECT STATEMENT Optimizer=CHOOSE (Cost=3 Card=1 Bytes=17)
1 0 SORT (AGGREGATE)
2 1 TABLE ACCESS (FULL) OF 'SALES_CONTACTS' (Cost=3 Card=16 Bytes=272)
Now we use a function based index
create index fbi on sale_contacts (UPPER(surname));
analyze index fbi compute statistics;
analyze table sale_contacts compute statistics;
SELECT count(*) FROM sale_contacts WHERE UPPER(surname) = 'ELLISON';
Execution Plan
0 SELECT STATEMENT Optimizer=CHOOSE (Cost=2 Card=1 Bytes=17)
1 0 SORT (AGGREGATE)
2 1 INDEX (RANGE SCAN) OF 'FBI' (NON-UNIQUE) (Cost=2 Card=381 Bytes=6477)
The function-based index has forced the optimizer to use index range scans (retuning zero or more rowids) on the surname column rather than doing a full table scan (non-index lookup). Optimal performance does vary depending on table size, uniqueness and selectivity of columns, use of fast full table scans etc. Therefore try both methods to gain optimal performance in your database.
It is important to remember that the function-based B*Tree index does not store the expression results in the index but uses an "expression tree". The optimizer performs expression matching by parsing the expression used in the SQL statement and comparing the results against the expression-tree values in the function-based index. This comparison IS case sensitive (ignores spaces) and therefore your function-based index expressions should match expressions used in the SQL statement where clauses.
Init.ora Parameters
The following parameter must be set in your parameter file: QUERY_REWRITE_INTEGRITY = TRUSTED
QUERY_REWRITE_ENABLED = TRUE
COMPATIBLE = 8.1.0.0.0 (or higher)
Grants
Grants To create function-based indexes the user must be granted CREATE INDEX and QUERY REWRITE, or alternatively be granted CREATE ANY INDEX and GLOBAL QUERY REWRITE. The index owner must have EXECUTE access on the function used for the index. If execute access is revoked then the function-based index will be "disabled" (see dba_indexes).
Disabled Indexes
If your function-based index has a status of "disabled" the DBA can do one of the following:
a) drop and create the index (take note of its current settings)
b) alter index enable, function-based indexes only, also use disable keyword as required
c) alter index unusable.
Queries on a DISABLED index fail if the optimizer chooses to use the index.Here is an example ORA error:
ERROR at line 1: ORA-30554: function-based index MYUSER.FBI is disabled.
All DML operations on a DISABLED index also fail unless the index is also marked UNUSABLE and the initialization parameter SKIP_UNUSABLE_INDEXES is set to true.
Some more Examples
CREATE INDEX expression_ndx
ON mytable ((mycola + mycolc) * mycolb);
SELECT mycolc FROM mytable
WHERE (mycola + mycolc) * mycolb <= 256;
..or a composite index..
CREATE INDEX example_ndx
ON myexample (mycola, UPPER(mycolb), mycolc);
SELECT mycolc FROM myexample
WHERE mycola = 55 AND UPPER(mycolb) = 'JONES';
Restriction & Rule Summary
The following restrictions apply to function based indexes. You may not index:
a) LOB columns
b) REF
c) Nested table column
d) Objects types with any of the above data types.
Function-based indexes must always follow these rules:
a) Cost Based optimizer only, must generate statistics after the index is created
b) Can not store NULL values (function can not return NULL under any circumstance)
c) If a user defined pl/sql routine is used for the function-based index, and is invalidated, the index will become "disabled"
d) Functions must be deterministic (always return the same value for a known input)
e) The index owner must have "execute" access on function used in the function-based index. Revocation of the privilege will render the index "disabled"
f) May have a B-Tree and Bitmap index type only
g) Can not use expressions that are based on aggregate functions, ie. SUM, AVG etc.
h) To alter a function-based index as enabled, the function used must be valid, deterministic and the signature of the function matches the signature of the function when it was created.
Joel P�rez

Full table scans : sql or server?

Thanks for taking my question!
We have 3 oracle servers (10.2.0.3). Each server has the same tables, data, and indexes but each can start acting different for no apparent reason. Sql that has runs for months goes bad on our production and test server while the production's backup server works fine.
In this case, I can fix the problem (as described below) but don’t understand what went wrong or why my change fixed the problem. Each server collects stats nightly so indexes and tables are not stale.
Anyone have any ideas why sql is breaks?
Thank You!
Kathie
BACKGOUND:
Sql works fine on 1 server and not on the other 2 servers (as I said before - same data and indexes on each server and sql has not changed on any of the servers).
TO FIX FULL TABLE SCAN:
MOVED: JOIN name_record n ON s.sr_key = n.nr_key AND n.nr_inactive_flag = 0
ADDED INDEX: (nr_key, nr_inactive_flag)
Already had an index with nr_key (which is unique) so it doesn't make since to add the new index but if I remove it the index the full table scan comes back.
*THIS IS THE ORIGINAL STATEMENT
SELECT ...sch.sch_name, sch.sch_state, v1.val_9pos AS sr_class_9,
v2.val_25pos AS sr_hsg_status_25, v3.val_25pos AS sr_hsg_list_25,
v4.val_9pos AS sr_selective_svc_9,
v5.val_madison AS sr_direct_deposit_10,
v6.val_3pos AS sr_for_lang_comp_3,
vtm1.vtm_13_display AS sr_matriculation_13,
vtm2.vtm_13_display AS last_ug_term,
vtm3.vtm_13_display AS last_g_term
FROM student_record s
JOIN user_names usr ON s.sr_public_w_check = usr.usr_key AND usr.usr_user_name = 'StudentUserID'
JOIN name_record n ON s.sr_key = n.nr_key AND n.nr_inactive_flag = 0JOIN value_terms vtm1 on s.sr_matriculation = vtm1.vtm_term
JOIN value_terms vtm2 ON s.sr_last_ug_term = vtm2.vtm_term
JOIN value_terms vtm3 ON s.sr_last_g_term = vtm3.vtm_term
JOIN value_master v1
ON v1.val_field = 205003 AND s.sr_class = v1.val_value_number
JOIN value_master v2
ON v2.val_field = 201204 AND s.sr_hsg_status = v2.val_value_number
JOIN value_master v3
ON v3.val_field = 201202 AND s.sr_hsg_list = v3.val_value_number
JOIN value_master v4
ON v4.val_field = 201173 AND s.sr_selective_svc = v4.val_value_number
JOIN value_master v5
ON v5.val_field = 201407 AND s.sr_direct_deposit = v5.val_value_number
JOIN value_master v6
ON v6.val_field = 201154 AND s.sr_for_lang_comp = v6.val_value_number
to here <<<<LEFT JOIN school_records sch ON s.sr_high_school =sch.SCH_TYPE_AND_CODE

Schizophrenic sql or server?.
C.

Slow queries and full table scans in spite of context index

I have defined a USER_DATASTORE, which uses a PL/SQL procedure to compile data from several tables. The master table has 1.3 million rows, and one of the fields being joined is a CLOB field.
The resulting token table has 65,000 rows, which seems about right.
If I query the token table for a word, such as "ORACLE" in the token_text field, I see that the token_count is 139. This query returns instantly.
The query against the master table is very slow, taking about 15 minutes to return the 139 rows.
Example query:
select hnd from master_table where contains(myindex,'ORACLE',1) > 0;
I've run a sql_trace on this query, and it shows full table scans on both the master table and the DR$MYINDEX$I table. Why is it doing this, and how can I fix it?

After looking at the tuning FAQ, I can see that this is doing a functional lookup instead of an indexed lookup. But why, when the rows are not constrained by any structural query, and how can I get it to instead to an indexed lookup?
Thanks in advance,
Annie

Taking more time in INDEX RANGE SCAN compare to the full table scan

Hi all ,
Below are the version og my database.
SQL> select * from v$version;
BANNER
Oracle Database 10g Enterprise Edition Release 10.2.0.4.0 - 64bi
PL/SQL Release 10.2.0.4.0 - Production
CORE 10.2.0.4.0 Production
TNS for HPUX: Version 10.2.0.4.0 - Production
NLSRTL Version 10.2.0.4.0 - Production
I have gather the table statistics and plan change for sql statment.
SELECT P1.COMPANY, P1.PAYGROUP, P1.PAY_END_DT, P1.PAYCHECK_OPTION,
P1.OFF_CYCLE, P1.PAGE_NUM, P1.LINE_NUM, P1.SEPCHK FROM PS_PAY_CHECK P1
WHERE P1.FORM_ID = :1 AND P1.PAYCHECK_NBR = :2 AND
P1.CHECK_DT = :3 AND P1.PAYCHECK_OPTION <> 'R'
Plan before the gather stats.
Plan hash value: 3872726522
| Id | Operation         | Name         | Rows | Bytes | Cost (%CPU)| Time     |
|   0 | SELECT STATEMENT |              |       |       | *14306* (100)|          |
|   1 | *TABLE ACCESS FULL| PS_PAY_CHECK* |     1 |    51 | 14306   (4)| 00:02:52 |
Plan after the gather stats:
Operation     Object Name     Rows     Bytes     Cost
SELECT STATEMENT Optimizer Mode=CHOOSE
          1           4
*TABLE ACCESS BY INDEX ROWID     SYSADM.PS_PAY_CHECK*     1     51     *4*
    *INDEX RANGE SCAN     SYSADM.PS0PAY_CHECK*     1           3After gather stats paln look good . but when i am exeuting the query it take 5 hours. before the gather stats it finishing the within 2 hours. i do not want to restore my old statistics. below are the data for the tables.and when i am obserrving it lot of db files scatter rea
NAME                                 TYPE        VALUE
_optimizer_cost_based_transformation string      OFF
filesystemio_options                 string      asynch
object_cache_optimal_size            integer     102400
optimizer_dynamic_sampling           integer     2
optimizer_features_enable            string      10.2.0.4
optimizer_index_caching              integer     0
optimizer_index_cost_adj             integer     100
optimizer_mode                       string      choose
optimizer_secure_view_merging        boolean     TRUE
plsql_optimize_level                 integer     2
SQL> select count(*) from sysadm.ps_pay_check;
select num_rows,blocks from dba_tables where table_name ='PS_PAY_CHECK';
COUNT(*)
   1270052
SQL> SQL> SQL>
NUM_ROWS     BLOCKS
   1270047      63166
Event                                 Waits    Time (s)   (ms)   Time Wait Class
db file sequential read           1,584,677       6,375      4   36.6   User I/O
db file scattered read            2,366,398       5,689      2   32.7   User I/Oplease let me know why it taking more time in INDEX RANGE SCAN compare to the full table scan?

suresh.ratnaji wrote:
NAME                                 TYPE        VALUE
_optimizer_cost_based_transformation string      OFF
filesystemio_options                 string      asynch
object_cache_optimal_size            integer     102400
optimizer_dynamic_sampling           integer     2
optimizer_features_enable            string      10.2.0.4
optimizer_index_caching              integer     0
optimizer_index_cost_adj             integer     100
optimizer_mode                       string      choose
optimizer_secure_view_merging        boolean     TRUE
plsql_optimize_level                 integer     2
please let me know why it taking more time in INDEX RANGE SCAN compare to the full table scan?Suresh,
Any particular reason why you have a non-default value for a hidden parameter, optimizercost_based_transformation ?
On my 10.2.0.1 database, its default value is "linear". What happens when you reset the value of the hidden parameter to default?

Why it is taking full table scan when index is available

Hi all,
I am facing a strange problem with index.
I created index on a column like
1. CREATE INDEX ASSETS_ARTIST_IDX2 ON ASSETS(artist).
SELECT asset.artist AS NAME FROM ASSETS asset WHERE asset.artist LIKE 'J%'
Explain Plan : INDEX RANGE SCAN
2. CREATE INDEX ASSETS_ARTIST_IDX2 ON ASSETS(UPPER (TRANSLATE (artist, ',;:"', ' ')));
SELECT asset.artist AS NAME FROM ASSETS asset WHERE UPPER (TRANSLATE (artist, ',;:"', ' ')) LIKE 'J%'
          Explain Plan : TABLE ACCESS FULL
first time it is taking index range scan,but in second situation scaning full table.Please let me know how to avoid the full table scan.
Regards,
Rajasekhar

Actually, I misseunderstood damorgan' s statement about NULL and OP did not provide table definition. So based on FTS I would say it is more likely column is NULLable, otherwise I would expect INDEX FAST SCAN:
SQL> create table emp1 as select * from emp
2 /
Table created.
SQL> create index emp1_idx1 on emp1(empno)
2 /
Index created.
SQL> exec dbms_stats.gather_table_stats('SCOTT','EMP1');
PL/SQL procedure successfully completed.
SQL> desc emp1
Name                                                                     Null?    Type
EMPNO                                                                             NUMBER(4)
ENAME                                                                             VARCHAR2(10)
JOB                                                                               VARCHAR2(9)
MGR                                                                               NUMBER(4)
HIREDATE                                                                          DATE
SAL                                                                               NUMBER(7,2)
COMM                                                                              NUMBER(7,2)
DEPTNO                                                                            NUMBER(2)
SQL> explain plan for
2 select empno
3 from emp1 where UPPER(TRANSLATE(empno, ',;:"', ' ')) LIKE '7%'
4 /
Explained.
SQL> @?\rdbms\admin\utlxpls
PLAN_TABLE_OUTPUT
Plan hash value: 2226897347
| Id | Operation         | Name | Rows | Bytes | Cost (%CPU)| Time     |
|   0 | SELECT STATEMENT |      |     1 |     4 |     3   (0)| 00:00:01 |
|* 1 | TABLE ACCESS FULL| EMP1 |     1 |     4 |     3   (0)| 00:00:01 |
Predicate Information (identified by operation id):
PLAN_TABLE_OUTPUT
   1 - filter(UPPER(TRANSLATE(TO_CHAR("EMPNO"),',;:"',' ')) LIKE '7%')
13 rows selected.
SQL> alter table emp1 modify empno not null
2 /
Table altered.
SQL> explain plan for
2 select empno
3 from emp1 where UPPER(TRANSLATE(empno, ',;:"', ' ')) LIKE '7%'
4 /
Explained.
SQL> @?\rdbms\admin\utlxpls
PLAN_TABLE_OUTPUT
Plan hash value: 2850860361
| Id | Operation        | Name      | Rows | Bytes | Cost (%CPU)| Time     |
|   0 | SELECT STATEMENT |           |     1 |     4 |     1   (0)| 00:00:01 |
|* 1 | INDEX FULL SCAN | EMP1_IDX1 |     1 |     4 |     1   (0)| 00:00:01 |
Predicate Information (identified by operation id):
PLAN_TABLE_OUTPUT
   1 - filter(UPPER(TRANSLATE(TO_CHAR("EMPNO"),',;:"',' ')) LIKE '7%')
13 rows selected.
SQL> SY.

Why full index scan is faster than full table scan?

Hi friends,
In the where clause of a query,if we give a column that contains index on it,then oracle uses index to search data rather than a TABLE ACCESS FULL Operation.
Why index searching is faster?

Sometimes it is faster to use index and sometimes it is faster to use full table scan. If your statistics are up to date Oracle is far more likely to get it right. If the query can be satisfied entirely from the index, then an index scan will almost always be faster as there are fewer blocks to read in the index than there would be if the table itself were scanned. However if the query must extract data from the table when that data is not in te index, then the index scan will be faster only if a small percentage of the rows are to be returned. Consiter the case of an index where 40% of the rows are returned. Assume the index values are distributed evenly among the data blocks. Assume 10 rows will fit in each data block thus 4 of the 10 rows will match the condition. Then the average datablock will be fetched 4 times since most of the time adjacent index entries will not be in the same block. The number of single datablock fetches will be about 4 times the number of datablocks. Compare this to a full table scan that does multiblock reads. Far fewer reads are required to read the entire table. Though it depends on the number of rows per block, a general rule is any query returning more than about 10% of a table is faster NOT using an index.

How to check small table scan full table scan if we will use index in where clause.

How to check small table scan full table scan if i will use index column in where clause.
Is there example link there i can test small table scan full table if index is used in where clause.

Use explain plan on your statement or set autotrace traceonly in your SQL*Plus session followed by the SQL you are testing.
For example
SQL> set autotrace traceonly
SQL> select *
2 from XXX
3 where id='fga';
no rows selected
Execution Plan
   0      SELECT STATEMENT Optimizer=ALL_ROWS (Cost=13 Card=1 Bytes=16
          5)
   1    0   PARTITION RANGE (ALL) (Cost=13 Card=1 Bytes=165)
   2    1     TABLE ACCESS (FULL) OF 'XXX' (TABLE) (Cost=13 Card
          =1 Bytes=165)
Statistics
          1 recursive calls
          0 db block gets
       1561 consistent gets
        540 physical reads
          0 redo size
       1864 bytes sent via SQL*Net to client
        333 bytes received via SQL*Net from client
          1 SQL*Net roundtrips to/from client
          0 sorts (memory)
          0 sorts (disk)
          0 rows processed

Bitmap index column goes for full table scan

Hi all,
Database : 10g R2
OS : Windows xp
my select query is :
SELECT tran_id, city_id, valid_records
FROM transaction_details
WHERE type_id=101;
And the Explain Plan is :
Plan
SELECT STATEMENT ALL_ROWSCost: 29 Bytes: 8,876 Cardinality: 634
1 TABLE ACCESS FULL TABLE TRANSACTION_DETAILS** Cost: 29 Bytes: 8,876 Cardinality: 634
total number of rows in the table = 1800 ;
distinct value of type_ids are 101,102,103
so i created a bit map index on it.
CREATE BITMAP INDEX btmp_typeid ON transaction_details
(type_id)
LOGGING
NOPARALLEL;
after creating the index, the explain plan shows the same. why it goes for full table scan?.
Kindly share ur idea on this.
Edited by: 887268 on Apr 3, 2013 11:01 PM
Edited by: 887268 on Apr 3, 2013 11:02 PM

>
I am sorry for being ignorant, can you please cite any scenario of locking due to bitmap indices? A link can be useful as well.
>
See my full reply in this thread
Bitmap index for FKs on Fact tables
>
ETL is affected because DML operations (INSERT/UPDATE/DELETE) on tables with bitmapped indexes can have serious performance issues due to the serialization involved. Updating a single bit-mapped column value (e.g. from 'M' to 'F' for gender) requires both bitmapped index blocks to be locked until the update is complete. A bitmap index stored ROWID ranges (min rowid - max rowid) than can span many, many records. The entire 'range' of rowids is locked in order to change just one value.
To change from 'M' the 'M' rowid range for that one row is locked and the ROWID must be removed from the range byt clearing the bit. To change to 'F' the 'F' rowid id range needs to be found, locked and the bit set that corresponds to that rowid. No other rows with rowids in the range can be changed since this is a serial operation. If the range includes 1000 rows and they all need changed it takes 1000 serial operations.

Order by column has index which results in full table scan

I have a query on table A which has index for column B.In the query i am using order by column B .In explain plan it shows that the full table scan is performed for table A without picking up the index for B .How can i ensure that index is picked up in the explain plan.Please help its urgent.
Pandu

Please help its urgent.Contact Oracle Support in that case.
By making that remark you have just made Blushadow go out to lunch (again) now.... ;)
Depending on your query a full scan could be 100% appropriate here.
But since you didn't post your DB_version, optimizer settings, execution plan etc. there's not much more to say, really, besides:
"Full scans aren't always evil".
See:
[When your query takes too long...|http://forums.oracle.com/forums/thread.jspa?messageID=3299435]
[How to post a SQLstatement Tuning Request|http://forums.oracle.com/forums/thread.jspa?threadID=863295&tstart=0]

VARRAY bind parameter in IN clause causes Full Table Scan

Hi
My problem is that Oracle elects to perform a full table scan when I want it to use an index.
The situation is this: I have a single table SQL query with an IN clause such as:
SELECT EMPNO, ENAME, JOB FROM EMP WHERE ENAME IN (...)
Since this is running in an application, I want to allow the user to provide a list of ENAMES to search. Because IN clauses don't accept bind parameters I've been using the Tom Kyte workaround which relies on setting a bind variable to an array-valued scalar, and then casting this array to be a table of records that the database can handle in an IN clause:
SELECT *
FROM EMP
WHERE ENAME IN (
SELECT *
FROM TABLE(CAST( ? AS TABLE_OF_VARCHAR)))
This resulted in very slow performance due to a full table scan. To test, I ran the SQL in SQL*Plus and provided the IN clause values in the query itself. The explain plan showed it using my index...ok good. But once I changed the IN clause to the 'select * from table...' syntax Oracle went into Full Scan mode. I added an index hint but it didn't change the plan. Has anyone had success using this technique without a full scan?
Thanks
John
p.s.
Please let me know if you think this should be posted on a different forum. Even though my context is a Java app developed with JDev this seemed like a SQL question.

Justin and 3360 - that was great advice and certainly nothing I would have come up with. However, as posted, the performance still wasn't good...but it gave me a term to Google on. I found this Ask Tom page http://asktom.oracle.com/pls/ask/f?p=4950:8:::::F4950_P8_DISPLAYID:3779680732446#15740265481549, where he included a seemingly magical 'where rownum >=0' which, when applied with your suggestions, turned my query from minutes into seconds.
My plans are as follows:
1 - Query with standard IN clause
SQL> explain plan for
2 select accession_number, protein_name, sequence_id from protein_dim
3 where accession_number in ('33460', '33458', '33451');
Explained.
SQL> select * from table(dbms_xplan.display);
PLAN_TABLE_OUTPUT
| Id | Operation | Name | Rows | Bytes | Cost |
| 0 | SELECT STATEMENT | | 7 | 336 | 4 |
| 1 | INLIST ITERATOR | | | | |
| 2 | TABLE ACCESS BY INDEX ROWID| PROTEIN_DIM | 7 | 336 | 4 |
| 3 | INDEX RANGE SCAN | IDX_PROTEIN_ACCNUM | 7 | | 3 |
Note: cpu costing is off, 'PLAN_TABLE' is old version
11 rows selected.
2 - Standard IN Clause with Index hint
SQL> explain plan for
2 select /*+ INDEX(protein_dim IDX_PROTEIN_ACCNUM) */
3 accession_number, protein_name, sequence_id, taxon_id, organism_name, data_source
4 from pdssuser.protein_dim
5 where accession_number in
6 ('33460', '33458', '33451');
Explained.
SQL> select * from table(dbms_xplan.display);
PLAN_TABLE_OUTPUT
| Id | Operation | Name | Rows | Bytes | Cost |
| 0 | SELECT STATEMENT | | 7 | 588 | 4 |
| 1 | INLIST ITERATOR | | | | |
| 2 | TABLE ACCESS BY INDEX ROWID| PROTEIN_DIM | 7 | 588 | 4 |
| 3 | INDEX RANGE SCAN | IDX_PROTEIN_ACCNUM | 7 | | 3 |
Note: cpu costing is off, 'PLAN_TABLE' is old version
11 rows selected.
3 - Using custom TABLE_OF_VARCHAR type
CREATE TYPE TABLE_OF_VARCHAR AS
TABLE OF VARCHAR2(50);
SQL> explain plan for
2 select
3 accession_number, protein_name, sequence_id, taxon_id, organism_name, data_source
4 from pdssuser.protein_dim
5 where accession_number in
6 (select * from table(cast(TABLE_OF_VARCHAR('33460', '33458', '33451') as TABLE_OF_VARCHAR)) t);
Explained.
SQL> select * from table(dbms_xplan.display);
PLAN_TABLE_OUTPUT
| Id | Operation | Name | Rows | Bytes | Cost |
| 0 | SELECT STATEMENT | | 2 | 168 | 57M|
| 1 | NESTED LOOPS SEMI | | 2 | 168 | 57M|
| 2 | TABLE ACCESS FULL | PROTEIN_DIM | 5235K| 419M| 13729 |
| 3 | COLLECTION ITERATOR CONSTRUCTOR FETCH| | | | |
Note: cpu costing is off, 'PLAN_TABLE' is old version
11 rows selected.
4 - Using custom TABLE_OF_VARCHAR type w/ Index hint
SQL> explain plan for
2 select /*+ INDEX(protein_dim IDX_PROTEIN_ACCNUM) */
3 accession_number, protein_name, sequence_id, taxon_id, organism_name, data_source
4 from pdssuser.protein_dim
5 where accession_number in
6 (select * from table(cast(TABLE_OF_VARCHAR('33460', '33458', '33451') as TABLE_OF_VARCHAR)) t);
Explained.
SQL> select * from table(dbms_xplan.display);
PLAN_TABLE_OUTPUT
| Id | Operation | Name | Rows | Bytes | Cost |
| 0 | SELECT STATEMENT | | 2 | 168 | 57M|
| 1 | NESTED LOOPS SEMI | | 2 | 168 | 57M|
| 2 | TABLE ACCESS BY INDEX ROWID | PROTEIN_DIM | 5235K| 419M| 252K|
| 3 | INDEX FULL SCAN | IDX_PROTEIN_ACCNUM | 5235K| | 17255 |
| 4 | COLLECTION ITERATOR CONSTRUCTOR FETCH| | | | |
PLAN_TABLE_OUTPUT
Note: cpu costing is off, 'PLAN_TABLE' is old version
12 rows selected.
5 - Using custom TABLE_OF_VARCHAR type w/ cardinality hint
SQL> explain plan for
2 select
3 accession_number, protein_name, sequence_id, taxon_id, organism_name, data_source from protein_dim
4 where accession_number in (select /*+ cardinality( t 10 ) */
5 * from TABLE(CAST (TABLE_OF_VARCHAR('33460', '33458', '33451') AS TABLE_OF_VARCHAR)) t);
Explained.
SQL> select * from table(dbms_xplan.display);
PLAN_TABLE_OUTPUT
| Id | Operation | Name | Rows | Bytes | Cost |
| 0 | SELECT STATEMENT | | 2 | 168 | 57M|
| 1 | NESTED LOOPS SEMI | | 2 | 168 | 57M|
| 2 | TABLE ACCESS FULL | PROTEIN_DIM | 5235K| 419M| 13729 |
| 3 | COLLECTION ITERATOR CONSTRUCTOR FETCH| | | | |
Note: cpu costing is off, 'PLAN_TABLE' is old version
11 rows selected.
6 - Using custom TABLE_OF_VARCHAR type w/ cardinality hint
and rownum >= 0 constraint
SQL> explain plan for
2 select
3 accession_number, protein_name, sequence_id, taxon_id, organism_name, data_source from protein_dim
4 where accession_number in (select /*+ cardinality( t 10 ) */
5 * from TABLE(CAST (TABLE_OF_VARCHAR('33460', '33458', '33451') AS TABLE_OF_VARCHAR)) t
6 where rownum >= 0);
Explained.
SQL> select * from table(dbms_xplan.display);
PLAN_TABLE_OUTPUT
| Id | Operation | Name | Rows | Bytes | Cost |
| 0 | SELECT STATEMENT | | 25 | 2775 | 43 |
| 1 | TABLE ACCESS BY INDEX ROWID | PROTEIN_DIM | 2 | 168 | 3 |
| 2 | NESTED LOOPS | | 25 | 2775 | 43 |
| 3 | VIEW | VW_NSO_1 | 10 | 270 | 11 |
| 4 | SORT UNIQUE | | 10 | | |
| 5 | COUNT | | | | |
| 6 | FILTER | | | | |
PLAN_TABLE_OUTPUT
| 7 | COLLECTION ITERATOR CONSTRUCTOR FETCH| | | | |
| 8 | INDEX RANGE SCAN | IDX_PROTEIN_ACCNUM | 2 | | 2 |
Note: cpu costing is off, 'PLAN_TABLE' is old version
16 rows selected.
I don't understand why performance improved so dramatically but happy that it did.
Thanks a ton!
John

Select statement in a function does Full Table Scan

All,
I have been coding a stored procedure that writes 38K rows in less than a minute. If I add another column which requires call to a package and 4 functions within that package, it runs for about 4 hours. I have confirmed that due to problems in one of the functions, the code does full table scans. The package and all of its functions were written by other contractors who have been long gone.
Please note that case_number_in (VARCHAR2) and effective_date_in (DATE) are parameters sent to the problem function and I have verified through TOAD’s debugger that their values are correct.
Table named ps2_benefit_register has over 40 million rows but case_number is an index for that table.
Table named ps1_case_fs has more than 20 million rows but also uses case_number as an index.
Select #1 – causes full table scan runs and writes 38K rows in a couple of hours.
{case}
SELECT max(a2.application_date)
INTO l_app_date
FROM dwfssd.ps2_benefit_register a1, dwfssd.ps2_case_fs a2
WHERE a2.case_number = case_number_in and
a1.case_number = a2.case_number and
a2.application_date <= effective_date_in and
a1.DOCUMENT_TYPE = 'F';
{case}
Select #2 – runs – hard coding values makes the code to write the same 38K rows in a few minutes.
{case}
SELECT max(a2.application_date)
INTO l_app_date
FROM dwfssd.ps2_benefit_register a1, dwfssd.ps2_case_fs a2
WHERE a2.case_number = 'A006438' and
a1.case_number = a2.case_number and
a2.application_date <= '01-Apr-2009' and
a1.DOCUMENT_TYPE = 'F';
{case}
Why using the values in the passed parameter in the first select statement causes full table scan?
Thank you for your help,
Seyed
Edited by: user11117178 on Jul 30, 2009 6:22 AM
Edited by: user11117178 on Jul 30, 2009 6:23 AM
Edited by: user11117178 on Jul 30, 2009 6:24 AM

Hello Dan,
Thank you for your input. The function is not determinsitic, therefore, I am providing you with the explain plan. By version number, if you are refering to the Database version, we are running 10g.
PLAN_TABLE_OUTPUT
Plan hash value: 2132048964
| Id | Operation                     | Name                    | Rows | Bytes | Cost (%CPU)| Time     | Pstart| Pstop |
|   0 | SELECT STATEMENT              |                         |   324K|    33M| 3138   (5)| 00:00:38 |       |       |
|* 1 | HASH JOIN                    |                         |   324K|    33M| 3138   (5)| 00:00:38 |       |       |
|   2 |   BITMAP CONVERSION TO ROWIDS |                         |     3 |     9 |     1   (0)| 00:00:01 |       |       |
|* 3 |    BITMAP INDEX FAST FULL SCAN| IDX_PS2_ACTION_TYPES    |       |       |            |          |       |       |
|   4 |   PARTITION RANGE ITERATOR    |                         |   866K|    87M| 3121   (4)| 00:00:38 |   154 |   158 |
|   5 |    TABLE ACCESS FULL          | PS2_FS_TRANSACTION_FACT |   866K|    87M| 3121   (4)| 00:00:38 |   154 |   158 |
Predicate Information (identified by operation id):
   1 - access("AL1"."ACTION_TYPE_ID"="AL2"."ACTION_TYPE_ID")
   3 - filter("AL2"."ACTION_TYPE"='1' OR "AL2"."ACTION_TYPE"='2' OR "AL2"."ACTION_TYPE"='S')
Thank you very much,
Seyed

URGENT HELP Required: Solution to avoid Full table scan for a PL/SQL query

Hi Everyone,
When I checked the EXPLAIN PLAN for the below SQL query, I saw that Full table scans is going on both the tables TABLE_A and TABLE_B
UPDATE TABLE_A a
SET a.current_commit_date =
(SELECT MAX (b.loading_date)
FROM TABLE_B b
WHERE a.sales_order_id = b.sales_order_id
AND a.sales_order_line_id = b.sales_order_line_id
AND b.confirmed_qty > 0
AND b.data_flag IS NULL
OR b.schedule_line_delivery_date >= '23 NOV 2008')
Though the TABLE_A is a small table having nearly 1 lakh records, the TABLE_B is a huge table, having nearly 2 and a half crore records.
I created an Index on the TABLE_B having all its fields used in the WHERE clause. But, still the explain plan is showing FULL TABLE SCAN only.
When I run the query, it is taking long long time to execute (more than 1 day) and each time I have to kill the session.
Please please help me in optimizing this.
Thanks,
Sudhindra

Check the instruction again, you're leaving out information we need in order to help you, like optimizer information.
- Post your exact database version, that is: the result of select * from v$version;
- Don't use TOAD's execution plan, but use
SQL> explain plan for <your_query>;
SQL> select * from table(dbms_xplan.display);(You can execute that in TOAD as well).
Don't forget you need to use the {noformat}{noformat} tag in order to post formatted code/output/execution plans etc.
It's also explained in the instruction.
When was the last time statistics were gathered for table_a and table_b?
You can find out by issuing the following query:select table_name
, last_analyzed
, num_rows
from user_tables
where table_name in ('TABLE_A', 'TABLE_B');
Can you also post the results of these counts;select count(*)
from table_b
where confirmed_qty > 0;
select count(*)
from table_b
where data_flag is null;
select count(*)
from table_b
where schedule_line_delivery_date >= /* assuming you're using a date, and not a string*/ to_date('23 NOV 2008', 'dd mon yyyy');

Preventing Discoverer using Full Table Scans with Decode in a View

Hi Forum,
Hope you are can help, it involves a performance issues when creating a Report / Query in Discoverer.
I have a Discoverer Report that currently takes less than 5 seconds to run. After I add a condition to bring back Batch Status that = Posted we cancelled the query after reaching 20 minutes as this is way too long. If I remove the condition the query time goes back to less than 5 seconds. Changing the condition to Batch Status that = Unposted returns the query in seconds.
Ive been doing some digging and have found the database view that is linked to the Journal Batches folder in Discoverer. See at end of post.
I think the problem is with the column using DECODE. When querying the column in TOAD the value of P is returned. But in discoverer the condition is done on the value Posted. Im not too sure how DECODE works, but think this could be the causing some sort of issue with Full Table Scans.
Any idea how do we get around this?
SELECT
JOURNAL_BATCH1.JE_BATCH_ID,
JOURNAL_BATCH1.NAME,
JOURNAL_BATCH1.SET_OF_BOOKS_ID,
GL_SET_OF_BOOKS.NAME,
DECODE( JOURNAL_BATCH1.STATUS,
'+', 'Unable to validate or create CTA',
'+*', 'Was unable to validate or create CTA',
'-','Invalid or inactive rounding differences account in journal entry',
'-*', 'Modified invalid or inactive rounding differences account in journal entry',
'<', 'Showing sequence assignment failure',
'<*', 'Was showing sequence assignment failure',
'>', 'Showing cutoff rule violation',
'>*', 'Was showing cutoff rule violation',
'A', 'Journal batch failed funds reservation',
'A*', 'Journal batch previously failed funds reservation',
'AU', 'Showing batch with unopened period',
'B', 'Showing batch control total violation',
'B*', 'Was showing batch control total violation',
'BF', 'Showing batch with frozen or inactive budget',
'BU', 'Showing batch with unopened budget year',
'C', 'Showing unopened reporting period',
'C*', 'Was showing unopened reporting period',
'D', 'Selected for posting to an unopened period',
'D*', 'Was selected for posting to an unopened period',
'E', 'Showing no journal entries for this batch',
'E*', 'Was showing no journal entries for this batch',
'EU', 'Showing batch with unopened encumbrance year',
'F', 'Showing unopened reporting encumbrance year',
'F*', 'Was showing unopened reporting encumbrance year',
'G', 'Showing journal entry with invalid or inactive suspense account',
'G*', 'Was showing journal entry with invalid or inactive suspense account',
'H', 'Showing encumbrance journal entry with invalid or inactive reserve account',
'H*', 'Was showing encumbrance journal entry with invalid or inactive reserve account',
'I', 'In the process of being posted',
'J', 'Showing journal control total violation',
'J*', 'Was showing journal control total violation',
'K', 'Showing unbalanced intercompany journal entry',
'K*', 'Was showing unbalanced intercompany journal entry',
'L', 'Showing unbalanced journal entry by account category',
'L*', 'Was showing unbalanced journal entry by account category',
'M', 'Showing multiple problems preventing posting of batch',
'M*', 'Was showing multiple problems preventing posting of batch',
'N', 'Journal produced error during intercompany balance processing',
'N*', 'Journal produced error during intercompany balance processing',
'O', 'Unable to convert amounts into reporting currency',
'O*', 'Was unable to convert amounts into reporting currency',
'P', 'Posted',
'Q', 'Showing untaxed journal entry',
'Q*', 'Was showing untaxed journal entry',
'R', 'Showing unbalanced encumbrance entry without reserve account',
'R*', 'Was showing unbalanced encumbrance entry without reserve account',
'S', 'Already selected for posting',
'T', 'Showing invalid period and conversion information for this batch',
'T*', 'Was showing invalid period and conversion information for this batch',
'U', 'Unposted',
'V', 'Journal batch is unapproved',
'V*', 'Journal batch was unapproved',
'W', 'Showing an encumbrance journal entry with no encumbrance type',
'W*', 'Was showing an encumbrance journal entry with no encumbrance type',
'X', 'Showing an unbalanced journal entry but suspense not allowed',
'X*', 'Was showing an unbalanced journal entry but suspense not allowed',
'Z', 'Showing invalid journal entry lines or no journal entry lines',
'Z*', 'Was showing invalid journal entry lines or no journal entry lines', NULL ),
DECODE( JOURNAL_BATCH1.ACTUAL_FLAG, 'A', 'Actual', 'B', 'Budget', 'E', 'Encumbrance', NULL ),
JOURNAL_BATCH1.DEFAULT_PERIOD_NAME,
JOURNAL_BATCH1.POSTED_DATE,
JOURNAL_BATCH1.DATE_CREATED,
JOURNAL_BATCH1.DESCRIPTION,
DECODE( JOURNAL_BATCH1.AVERAGE_JOURNAL_FLAG, 'N', 'Standard', 'Y', 'Average', NULL ),
DECODE( JOURNAL_BATCH1.BUDGETARY_CONTROL_STATUS, 'F', 'Failed', 'I', 'In Process', 'N', 'N/A', 'P', 'Passed', 'R', 'Required', NULL ),
DECODE( JOURNAL_BATCH1.APPROVAL_STATUS_CODE, 'A', 'Approved', 'I', 'In Process', 'J', 'Rejected', 'R', 'Required', 'V','Validation Failed','Z', 'N/A',NULL ),
JOURNAL_BATCH1.CONTROL_TOTAL,
JOURNAL_BATCH1.RUNNING_TOTAL_DR,
JOURNAL_BATCH1.RUNNING_TOTAL_CR,
JOURNAL_BATCH1.RUNNING_TOTAL_ACCOUNTED_DR,
JOURNAL_BATCH1.RUNNING_TOTAL_ACCOUNTED_CR,
JOURNAL_BATCH1.PARENT_JE_BATCH_ID,
JOURNAL_BATCH2.NAME
FROM
GL_JE_BATCHES JOURNAL_BATCH1,
GL_JE_BATCHES JOURNAL_BATCH2,
GL_SETS_OF_BOOKS
GL_SET_OF_BOOKS
WHERE
JOURNAL_BATCH1.PARENT_JE_BATCH_ID = JOURNAL_BATCH2.JE_BATCH_ID (+) AND
JOURNAL_BATCH1.SET_OF_BOOKS_ID = GL_SET_OF_BOOKS.SET_OF_BOOKS_ID AND
GL_SECURITY_PKG.VALIDATE_ACCESS( JOURNAL_BATCH1.SET_OF_BOOKS_ID ) = 'TRUE' WITH READ ONLY
Thanks,
Lance

Discoverer created it's own SQL.
Please see below the SQL Inspector Plan:
Before Condition
SELECT STATEMENT
SORT GROUP BY
VIEW SYS
SORT GROUP BY
NESTED LOOPS OUTER
NESTED LOOPS OUTER
NESTED LOOPS
NESTED LOOPS
NESTED LOOPS
NESTED LOOPS OUTER
NESTED LOOPS OUTER
NESTED LOOPS
NESTED LOOPS OUTER
NESTED LOOPS OUTER
NESTED LOOPS
NESTED LOOPS
NESTED LOOPS
NESTED LOOPS
NESTED LOOPS
NESTED LOOPS
NESTED LOOPS
NESTED LOOPS
NESTED LOOPS
NESTED LOOPS
NESTED LOOPS
TABLE ACCESS BY INDEX ROWID GL.GL_CODE_COMBINATIONS
AND-EQUAL
INDEX RANGE SCAN GL.GL_CODE_COMBINATIONS_N2
INDEX RANGE SCAN GL.GL_CODE_COMBINATIONS_N1
TABLE ACCESS BY INDEX ROWID APPLSYS.FND_FLEX_VALUES
INDEX RANGE SCAN APPLSYS.FND_FLEX_VALUES_N1
TABLE ACCESS BY INDEX ROWID APPLSYS.FND_FLEX_VALUE_SETS
INDEX UNIQUE SCAN APPLSYS.FND_FLEX_VALUE_SETS_U1
TABLE ACCESS BY INDEX ROWID APPLSYS.FND_FLEX_VALUES_TL
INDEX UNIQUE SCAN APPLSYS.FND_FLEX_VALUES_TL_U1
INDEX RANGE SCAN APPLSYS.FND_FLEX_VALUE_NORM_HIER_U1
TABLE ACCESS BY INDEX ROWID GL.GL_JE_LINES
INDEX RANGE SCAN GL.GL_JE_LINES_N1
INDEX UNIQUE SCAN GL.GL_JE_HEADERS_U1
INDEX UNIQUE SCAN GL.GL_SETS_OF_BOOKS_U2
TABLE ACCESS BY INDEX ROWID GL.GL_JE_HEADERS
INDEX UNIQUE SCAN GL.GL_JE_HEADERS_U1
INDEX UNIQUE SCAN GL.GL_DAILY_CONVERSION_TYPES_U1
TABLE ACCESS BY INDEX ROWID GL.GL_JE_SOURCES_TL
INDEX UNIQUE SCAN GL.GL_JE_SOURCES_TL_U1
INDEX UNIQUE SCAN GL.GL_JE_CATEGORIES_TL_U1
INDEX UNIQUE SCAN GL.GL_JE_HEADERS_U1
INDEX UNIQUE SCAN GL.GL_JE_HEADERS_U1
INDEX UNIQUE SCAN GL.GL_JE_BATCHES_U1
INDEX UNIQUE SCAN GL.GL_BUDGET_VERSIONS_U1
INDEX UNIQUE SCAN GL.GL_ENCUMBRANCE_TYPES_U1
INDEX UNIQUE SCAN GL.GL_SETS_OF_BOOKS_U2
TABLE ACCESS BY INDEX ROWID GL.GL_JE_BATCHES
INDEX UNIQUE SCAN GL.GL_JE_BATCHES_U1
INDEX UNIQUE SCAN GL.GL_SETS_OF_BOOKS_U2
INDEX UNIQUE SCAN GL.GL_JE_BATCHES_U1
TABLE ACCESS BY INDEX ROWID GL.GL_PERIODS
INDEX RANGE SCAN GL.GL_PERIODS_U1
After Condition
SELECT STATEMENT
SORT GROUP BY
VIEW SYS
SORT GROUP BY
NESTED LOOPS
NESTED LOOPS OUTER
NESTED LOOPS OUTER
NESTED LOOPS
NESTED LOOPS
NESTED LOOPS
NESTED LOOPS
NESTED LOOPS OUTER
NESTED LOOPS
NESTED LOOPS
NESTED LOOPS
NESTED LOOPS
NESTED LOOPS
NESTED LOOPS
NESTED LOOPS OUTER
NESTED LOOPS
NESTED LOOPS OUTER
NESTED LOOPS
NESTED LOOPS
NESTED LOOPS OUTER
NESTED LOOPS
TABLE ACCESS FULL GL.GL_JE_BATCHES
INDEX UNIQUE SCAN GL.GL_SETS_OF_BOOKS_U2
INDEX UNIQUE SCAN GL.GL_JE_BATCHES_U1
TABLE ACCESS BY INDEX ROWID GL.GL_JE_HEADERS
INDEX RANGE SCAN GL.GL_JE_HEADERS_N1
INDEX UNIQUE SCAN GL.GL_SETS_OF_BOOKS_U2
INDEX UNIQUE SCAN GL.GL_ENCUMBRANCE_TYPES_U1
INDEX UNIQUE SCAN GL.GL_DAILY_CONVERSION_TYPES_U1
INDEX UNIQUE SCAN GL.GL_BUDGET_VERSIONS_U1
TABLE ACCESS BY INDEX ROWID GL.GL_JE_SOURCES_TL
INDEX UNIQUE SCAN GL.GL_JE_SOURCES_TL_U1
INDEX UNIQUE SCAN GL.GL_JE_CATEGORIES_TL_U1
INDEX UNIQUE SCAN GL.GL_JE_BATCHES_U1
TABLE ACCESS BY INDEX ROWID GL.GL_JE_LINES
INDEX RANGE SCAN GL.GL_JE_LINES_U1
INDEX UNIQUE SCAN GL.GL_SETS_OF_BOOKS_U2
TABLE ACCESS BY INDEX ROWID GL.GL_CODE_COMBINATIONS
INDEX UNIQUE SCAN GL.GL_CODE_COMBINATIONS_U1
TABLE ACCESS BY INDEX ROWID GL.GL_PERIODS
INDEX RANGE SCAN GL.GL_PERIODS_U1
TABLE ACCESS BY INDEX ROWID APPLSYS.FND_FLEX_VALUES
INDEX RANGE SCAN APPLSYS.FND_FLEX_VALUES_N1
INDEX RANGE SCAN APPLSYS.FND_FLEX_VALUE_NORM_HIER_U1
TABLE ACCESS BY INDEX ROWID APPLSYS.FND_FLEX_VALUES_TL
INDEX UNIQUE SCAN APPLSYS.FND_FLEX_VALUES_TL_U1
TABLE ACCESS BY INDEX ROWID APPLSYS.FND_FLEX_VALUE_SETS
INDEX UNIQUE SCAN APPLSYS.FND_FLEX_VALUE_SETS_U1
INDEX UNIQUE SCAN GL.GL_JE_HEADERS_U1
INDEX UNIQUE SCAN GL.GL_JE_HEADERS_U1
INDEX UNIQUE SCAN GL.GL_JE_HEADERS_U1
_________________________________

How to avoid full Table scan when using Rule based optimizer (Oracle817)

1. We have a Oracle 8.1.7 DB, and the optimizer_mode is set to "RULE"
2. There are three indexes on table cm_contract_supply, which is a large table having 28732830 Rows, and average row length 149 Bytes
COLUMN_NAME INDEX_NAME
PROGRESS_RECID XAK11CM_CONTRACT_SUPPLY
COMPANY_CODE XIE1CM_CONTRACT_SUPPLY
CONTRACT_NUMBER XIE1CM_CONTRACT_SUPPLY
COUNTRY_CODE XIE1CM_CONTRACT_SUPPLY
SUPPLY_TYPE_CODE XIE1CM_CONTRACT_SUPPLY
VERSION_NUMBER XIE1CM_CONTRACT_SUPPLY
CAMPAIGN_CODE XIF1290CM_CONTRACT_SUPPLY
COMPANY_CODE XIF1290CM_CONTRACT_SUPPLY
COUNTRY_CODE XIF1290CM_CONTRACT_SUPPLY
SUPPLIER_BP_ID XIF801CONTRACT_SUPPLY
COMMISSION_LETTER_CODE XIF803CONTRACT_SUPPLY
COMPANY_CODE XIF803CONTRACT_SUPPLY
COUNTRY_CODE XIF803CONTRACT_SUPPLY
COMPANY_CODE XPKCM_CONTRACT_SUPPLY
CONTRACT_NUMBER XPKCM_CONTRACT_SUPPLY
COUNTRY_CODE XPKCM_CONTRACT_SUPPLY
SUPPLY_SEQUENCE_NUMBER XPKCM_CONTRACT_SUPPLY
VERSION_NUMBER XPKCM_CONTRACT_SUPPLY
3. We are querying the table for a particular contract_number and version_number. We want to avoid full table scan.
SELECT /*+ INDEX(XAK11CM_CONTRACT_SUPPLY) */
rowid, pms.cm_contract_supply.*
FROM pms.cm_contract_supply
WHERE
contract_number = '0000000000131710'
AND version_number = 3;
However despite of giving hint, query results are fetched after full table scan.
Execution Plan
0 SELECT STATEMENT Optimizer=RULE (Cost=1182 Card=1 Bytes=742)
1 0 TABLE ACCESS (FULL) OF 'CM_CONTRACT_SUPPLY' (Cost=1182 Card=1 Bytes=742)
4. I have tried giving
SELECT /*+ FIRST_ROWS + INDEX(XAK11CM_CONTRACT_SUPPLY) */
rowid, pms.cm_contract_supply.*
FROM pms.cm_contract_supply
WHERE
contract_number = '0000000000131710'
AND version_number = 3;
and
SELECT /*+ CHOOSE + INDEX(XAK11CM_CONTRACT_SUPPLY) */
rowid, pms.cm_contract_supply.*
FROM pms.cm_contract_supply
WHERE
contract_number = '0000000000131710'
AND version_number = 3;
But it does not work.
Is there some way without changing optimizer mode and without creating an additional index, we can use the index instead of full table scan?

David,
Here is my test on a Oracle 10g database.
SQL> create table mytable as select * from all_tables;
Table created.
SQL> set autot traceonly
SQL> alter session set optimizer_mode = choose;
Session altered.
SQL> select count(*) from mytable;
Execution Plan
   0      SELECT STATEMENT Optimizer=CHOOSE
   1    0   SORT (AGGREGATE)
   2    1     TABLE ACCESS (FULL) OF 'MYTABLE' (TABLE)
Statistics
          1 recursive calls
          0 db block gets
         29 consistent gets
          0 physical reads
          0 redo size
        223 bytes sent via SQL*Net to client
        276 bytes received via SQL*Net from client
          2 SQL*Net roundtrips to/from client
          0 sorts (memory)
          0 sorts (disk)
          1 rows processed
SQL> analyze table mytable compute statistics;
Table analyzed.
SQL> select count(*) from mytable
2 ;
Execution Plan
   0      SELECT STATEMENT Optimizer=CHOOSE (Cost=11 Card=1)
   1    0   SORT (AGGREGATE)
   2    1     TABLE ACCESS (FULL) OF 'MYTABLE' (TABLE) (Cost=11 Card=1
          788)
Statistics
          1 recursive calls
          0 db block gets
         29 consistent gets
          0 physical reads
          0 redo size
        222 bytes sent via SQL*Net to client
        276 bytes received via SQL*Net from client
          2 SQL*Net roundtrips to/from client
          0 sorts (memory)
          0 sorts (disk)
          1 rows processed
SQL> disconnect
Disconnected from Oracle Database 10g Enterprise Edition Release 10.1.0.2.0 - 64bit Production
With the Partitioning, Oracle Label Security, OLAP and Data Mining options

Associative Arrays, Indexes vs. Full Table Scans

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