Explain Plan in SQL Developer 1.5.1

How do I run Explain Plan against a Stored Package using SQL Developer 1.5.1?
I'm not familiar with this tool and need to examine a specific package.
Thanks.

AFAIK, you can only get an explain plan for SQL statements, not PL/SQL code...
K.

Similar Messages

Explain Plan in SQL Developer vs. SQLPlus

Hi everyone,
I've got a quick question. Why would an explain plan hang in SQL Developer but come back immediately in SQL Plus?
For example, in SQL developer, I write my statement and use the F6 command to bring up the explain plan and it just hangs and hangs. It looks like it's trying to generate an explain plan, but it's been running for hours now.
When I log into SQL Plus, I do a
SQL> explain plan for <query>:
SQL> select * from table(dbms_xplan.display);That whole process takes less than a minute to get the explain plan.
Is there something fundamentally different being executed by SQL Developer?
Thanks!
-Joe

Joe,
F6 in SQL Developer runs an AutoTrace, which actually runs the SQL and also displays timings and the explain plan. If you only want the explain plan, use F10.
Regards,
Bob

What are the permissions needed to run explain plans via sql develeper?

Are the permissions the same in Sql Developer to run explain plans like they are when you run them via sql*plus?

Yes same permission because the explain plan does not tie to the tools.

Explain plan and SQL profile.

Hi ,
I got a sql tuning result for one query , and i need to understand the below fileds in the explain plan
operation lineid object object_type order rows bytes cost time cpucost iocost
any document to understand will be appreciated
and in recomendation i got Consider accepting the recommended SQL profile. suppose if it was not feasible after accepting the SQL profile can i revert back.
Thanks

user12266475 wrote:
Hi ,
I got a sql tuning result for one query , and i need to understand the below fileds in the explain plan
operation lineid object object_type order rows bytes cost time cpucost iocost
any document to understand will be appreciated
and in recomendation i got Consider accepting the recommended SQL profile. suppose if it was not feasible after accepting the SQL profile can i revert back.
Thankshttp://docs.oracle.com/cd/E11882_01/server.112/e16638/toc.htm
Thread: HOW TO: Post a SQL statement tuning request - template posting
HOW TO: Post a SQL statement tuning request - template posting

Efficient way to read through big explain plan and genterate html explain plan for sql id's executed in past

Hi,
I have a sql which is recently having a performance problems in Production. I have generated a explain plan for it trying to find out what it is doing but plan itself is close to 1000 lines. I want to check if there is any efficient way to go through big plan like this one and quickly find the damaging areas..
2) I also wanted to know if there is way to generate explain plans in HTML format which executed in past and have entry in dba_hist_sqltext.
3) I also have two sql_monitor reports which I want to compare. is there any efficient way to do it as well?
Please share your thoughts!
Thanks in advance!
Regards,
Suman-

Hi,
I suggest you can try running sql advisor on the query maybe something fruitful comes up
http://www.oracle-base.com/articles/11g/sql-access-advisor-11gr1.php
I am not sure about the explain plan being printed in html format but
You may also want to try the sqlhistory.sql query from below page
http://evdbt.com/scripts/
I have used it many times to check on executions and explain plans which may have changed over the period
I have faced it many times , the query picks up a bad explain plan and performs poorly

Explain plan for SQL running in a session

Hi. Can you get the explain plan information for sql that's currently running in a session? I know I can use the session report to see the active SQL, but I don't know if it's possible to get the explain plan information from there, like you can with TOAD's session manager.

I've put together a query for the v$sql_plan in 9iR2.
Depending on what you use, you can probably drop some columns (eg OTHER and partition columns) and you could drive it from the v$session by getting the hash_value from there for the sid you are interested in :
(select * from v$sql_plan where hash_value =
(select sql_hash_value from v$session where sid=:sid))
select level, optimizer, lpad('_',1*(level-1),'_')||operation operation,
options, object_owner||'.'||object_name obj_name, search_columns,
ltrim(to_char(cardinality,'999,999,999')) no_rows,
ltrim(to_char(bytes/1024,'999,999')) kbytes, cost tot_cost,
object_node link, id, parent_id, other_tag||':'||other other,
partition_start, partition_stop, cpu_cost, io_cost,
access_predicates, filter_predicates,
round(temp_space/(1024*1024),2) temp_space_mb
from (select * from v$sql_plan where hash_value = :hash_val)
start with id=0
connect by prior id = parent_id and prior child_number = child_number
order by child_number, id, position;

Is plan_table necessary for an explain plan?

Hi, I've noticed that an explain plan for a query can be obtained by setting autotrace on. However, when I get a result from the autotrace, it shows no records in the plan_table table. I just want to check with others to make sure it's clear that a plan_table table isn't necessary to obtain an explain plan for a query. I've also noticed that when I hit the explain plan button in sql developer, there's no records in the plan_table table.

Girish Sharma wrote:
arizona9952 wrote:
Hi, I've noticed that an explain plan for a query can be obtained by setting autotrace on. However, when I get a result from the autotrace, it shows no records in the plan_table table. I just want to check with others to make sure it's clear that a plan_table table isn't necessary to obtain an explain plan for a query. I've also noticed that when I hit the explain plan button in sql developer, there's no records in the plan_table table.What is your sql developer version ? If it is 3.0 then sql developer rollbacks the rows after fetching the plan for display. So you must rely on the Autotrace or Explain Plan result tabs.
Similar discussion in below thread:
Choose specific plan_table in SQL Developer 2+?
Regards
Girish SharmaThanks Girish. I'm running SQL developer version 3.1, so that explains why the plan_table table shows empty after I run an explain plan in SQL developer.

Explain Plan in sqldevloper

Hi,
in sqldevloper 3.1.07 some users (system or those with DBA role) can generate an explain plan but not all users.
Is there any option or privilege to grant ?
Thank you.

F6 : in SQL Developer runs an AutoTrace,and actually runs the SQL and also displays timings and the explain plan.
F10. : explain plan
Read
http://www.thatjeffsmith.com/archive/2012/02/quick-tip-comparing-explain-plans-with-sql-developer/

Explain Plan Optimizer

How do you change the optimizer used by the explain plan in SQL Developer? It seems to only allow you to let Oracle choose. I would like the ability to run it by different optimizers.

Choose usually equals CBO. That may have been a typo or something. In a perfect world, you set the database to choose and everything works optimally. In reality, the CBO, while being very good, is not perfect. The old adage of 'garbage in, garbage out' becomes very evident when using the CBO because bad, or incomplete stats can cause it to behave badly and complex queries can confuse it as well.
Query help:
asktom.oracle.com - Tom Kite is probably the best performance guy in the world for Oracle. His site has tons of help and insight into how the database works. He also has a few books.
http://asktom.oracle.com/pls/ask/f?p=4950:8:9438791572789777368::NO::F4950_P8_DISPLAYID,F4950_P8_CRITERIA:231814117467
Oracle has a classroom training program for query performance tuning. It is pretty good and any serious oracle developer should probably pony up the cash for that course.
http://education.oracle.com/pls/web_prod-plq-dad/show_desc.redirect?dc=D17265GC10&p_org_id=1001&lang=US&source_call=
or search for 'SQL Tuning' on education.oracle.com
Also, oracle's documentation on tuning is pretty good. Tom's thread that I linked to above points to oracle's documentation.
As for why an outer join would invalidate an index. In most cases, the reason behind that is because an index, unless specially written, will not index a null value. Therefore, depending upon the direction of the outer join, it may not be able to use the index since it needs to return the nulls on one side. Also, under the CBO, if it detects that a lot of rows will be returned, or more correctly, need to be read, it will usually choose to perform full table scans with hash or merge joins because it is faster and more efficient than reading tons of rowids from the index and one by one reading the row data.
I had better leave it at that. We are not exactly on the correct forum to discuss query tuning. That is probably best done on the sql and pl/sql forum or asktom.oracle.com. Hopefully I have pointed you to the resources that you need.
Best of luck.
Eric

Sql Explain Plan

Hi Guys
I am new to SQL Tuning and i wanna know what exactly are the tables involved in finding the explain plan of sql's and what all the views that needs to be queried to find the explain lan of a query. Kindly help me .
Thanks
Ram

plan_table is used to get execution plan of any query. this table can be created with the script utlxplan.sql. You can find the script under ORACLE_HOME/rdbms/admin folder.
The process for getting the execution plan is
SQL> explain plan for
2 select * from emp where employee_id=12 ;
Explained.
SQL> select plan_table_output from table(dbms_xplan.display('plan_table',null,'serial'));
you can run the utlxpls.sql script also to get formated output and which can be found in ORACLE_HOME/rdbms/admin folder.
PLAN_TABLE_OUTPUT
| Id | Operation | Name | Rows | Bytes | Cost (%CPU) |
| 0 | SELECT STATEMENT | | 1 | 42 | 3 (0)|
|* 1 | TABLE ACCESS FULL | EMP | 1 | 42 | 3 (0)|
Predicate Information (identified by operation id):
PLAN_TABLE_OUTPUT
1 - filter("EMPLOYEE_ID"=12)

Explain plan different for same query

Hi all,
I have a query, which basically selects some columns from a remote database view. The query is as follows:
select * from tab1@remotedb, tab2@remotedb
where tab1.cash_id = tab2.id
and tab1.date = '01-JAN-2003'
and tab2.country_code = 'GB';
Now, i am working on two environments, one is production and other is development. Production environment has following specification:
1. Remotedb = Oracle9i, Linux OS
2. Database on which query is running = Oracle10g, Linux OS
Development environment has following specification:
1. Remotedb = Oracle10g, Windows OS
2. Database on which query is running = Oracle10g, Linux OS
Both databases in development and production environments are on different machines.
when i execute the above query on production, i see full table scans on both tables in execution plan(TOAD), but when i execute the query in development, i see that both remote database tables are using index.
Why am i getting different execution plans on both databases? is there is any difference of user rights/priviliges or there is a difference of statistics on both databases. I have checked the statistics for both tables on Production and Development databases, they are updated.
This issue is creating a performance disaster in our Production system. Any kind of help or knowledge sharing is appreciated.
Thank you and Best Regards.

We ran into a similar situation yesterday morning, though our implementation was easier than yours. Different plans in development and production though both systems were 10gR2 at the time. Production was doing a Merge Join Cartesian (!) instead of nested loop joins. Our DBA figured out that the production stats had been locked for some tables preventing stat refresh; she unlocked them and re-analyzed so which fixed our problem.
Of some interest was discovering that I got different execution plans from the same UPDATE via EXPLAIN PLAN and SQL*PLUS AUTOTRACE in development. Issue appears to have been bind peeking. Converting bind variables to constants yielded the AUTOTRACE plan, as did turning bind peeking off while using the bind variables. CURSOR_SHARING was set to EXACT too.
Message was edited by:
riedelme

Printing of Explain Plan Results

Is there any way to print an explain plan in SQL Devveloper when the length of the plan result requires scrolling to view the entire plan. I've tried expanding the plan result window as much as possible. The print result contains only what can be viewed.

I haven't tried DBMS_XPLAN but I'll look it up.
I can generate explain plans in a manner that's acceptable to read by simply using SQL*Plus.
This thread was about evaluating the features and problems with SQL*Developer. What I'm saying with this posting is that there is a problem with printing the explain plans that are generated in SQL*Developer when the plan result extend past the viewed window.
Is there a way to send this problem with the Oracle devlopers the way we do with SRs in Metalink? I didn't know if it was appropriate to send this through Metalink. I thought Oracle was monitoring this Forum for issues that were discovered with SQL*Developer.

How to improve the query performance or tune query from Explain Plan

Hi
The following is my explain plan for sql query. (The plan is generated by Toad v9.7). How to fix the query?
SELECT STATEMENT ALL_ROWSCost: 4,160 Bytes: 25,296 Cardinality: 204
     8 NESTED LOOPS Cost: 3 Bytes: 54 Cardinality: 1
          5 NESTED LOOPS Cost: 2 Bytes: 23 Cardinality: 1
               2 TABLE ACCESS BY INDEX ROWID TABLE AR.RA_CUSTOMER_TRX_ALL Cost: 1 Bytes: 13 Cardinality: 1
                    1 INDEX UNIQUE SCAN INDEX (UNIQUE) AR.RA_CUSTOMER_TRX_U1 Cost: 1 Cardinality: 1
               4 TABLE ACCESS BY INDEX ROWID TABLE AR.HZ_CUST_ACCOUNTS Cost: 1 Bytes: 10 Cardinality: 1
                    3 INDEX UNIQUE SCAN INDEX (UNIQUE) AR.HZ_CUST_ACCOUNTS_U1 Cost: 1 Cardinality: 1
          7 TABLE ACCESS BY INDEX ROWID TABLE AR.HZ_PARTIES Cost: 1 Bytes: 31 Cardinality: 1
               6 INDEX UNIQUE SCAN INDEX (UNIQUE) AR.HZ_PARTIES_U1 Cost: 1 Cardinality: 1
     10 TABLE ACCESS BY INDEX ROWID TABLE AR.RA_CUSTOMER_TRX_ALL Cost: 1 Bytes: 12 Cardinality: 1
          9 INDEX UNIQUE SCAN INDEX (UNIQUE) AR.RA_CUSTOMER_TRX_U1 Cost: 1 Cardinality: 1
     15 NESTED LOOPS Cost: 2 Bytes: 29 Cardinality: 1
          12 TABLE ACCESS BY INDEX ROWID TABLE AR.RA_CUSTOMER_TRX_ALL Cost: 1 Bytes: 12 Cardinality: 1
               11 INDEX UNIQUE SCAN INDEX (UNIQUE) AR.RA_CUSTOMER_TRX_U1 Cost: 1 Cardinality: 1
          14 TABLE ACCESS BY INDEX ROWID TABLE ONT.OE_ORDER_HEADERS_ALL Cost: 1 Bytes: 17 Cardinality: 1
               13 INDEX RANGE SCAN INDEX (UNIQUE) ONT.OE_ORDER_HEADERS_U2 Cost: 1 Cardinality: 1
     21 FILTER
          16 TABLE ACCESS FULL TABLE ONT.OE_TRANSACTION_TYPES_TL Cost: 2 Bytes: 1,127 Cardinality: 49
          20 NESTED LOOPS Cost: 2 Bytes: 21 Cardinality: 1
               18 TABLE ACCESS BY INDEX ROWID TABLE AR.RA_CUSTOMER_TRX_ALL Cost: 1 Bytes: 12 Cardinality: 1
                    17 INDEX UNIQUE SCAN INDEX (UNIQUE) AR.RA_CUSTOMER_TRX_U1 Cost: 1 Cardinality: 1
               19 INDEX RANGE SCAN INDEX (UNIQUE) ONT.OE_ORDER_HEADERS_U2 Cost: 1 Bytes: 9 Cardinality: 1
     23 TABLE ACCESS BY INDEX ROWID TABLE AR.RA_CUSTOMER_TRX_ALL Cost: 1 Bytes: 12 Cardinality: 1
          22 INDEX UNIQUE SCAN INDEX (UNIQUE) AR.RA_CUSTOMER_TRX_U1 Cost: 1 Cardinality: 1
     45 NESTED LOOPS Cost: 4,160 Bytes: 25,296 Cardinality: 204
          42 NESTED LOOPS Cost: 4,150 Bytes: 23,052 Cardinality: 204
               38 NESTED LOOPS Cost: 4,140 Bytes: 19,992 Cardinality: 204
                    34 NESTED LOOPS Cost: 4,094 Bytes: 75,850 Cardinality: 925
                         30 NESTED LOOPS Cost: 3,909 Bytes: 210,843 Cardinality: 3,699
                              26 PARTITION LIST ALL Cost: 2,436 Bytes: 338,491 Cardinality: 14,717 Partition #: 29 Partitions accessed #1 - #18
                                   25 TABLE ACCESS BY LOCAL INDEX ROWID TABLE XLA.XLA_AE_HEADERS Cost: 2,436 Bytes: 338,491 Cardinality: 14,717 Partition #: 29 Partitions accessed #1 - #18
                                        24 INDEX SKIP SCAN INDEX XLA.XLA_AE_HEADERS_N1 Cost: 264 Cardinality: 1,398,115 Partition #: 29 Partitions accessed #1 - #18
                              29 PARTITION LIST ITERATOR Cost: 1 Bytes: 34 Cardinality: 1 Partition #: 32
                                   28 TABLE ACCESS BY LOCAL INDEX ROWID TABLE XLA.XLA_AE_LINES Cost: 1 Bytes: 34 Cardinality: 1 Partition #: 32
                                        27 INDEX RANGE SCAN INDEX (UNIQUE) XLA.XLA_AE_LINES_U1 Cost: 1 Cardinality: 1 Partition #: 32
                         33 PARTITION LIST ITERATOR Cost: 1 Bytes: 25 Cardinality: 1 Partition #: 35
                              32 TABLE ACCESS BY LOCAL INDEX ROWID TABLE XLA.XLA_DISTRIBUTION_LINKS Cost: 1 Bytes: 25 Cardinality: 1 Partition #: 35
                                   31 INDEX RANGE SCAN INDEX XLA.XLA_DISTRIBUTION_LINKS_N3 Cost: 1 Cardinality: 1 Partition #: 35
                    37 PARTITION LIST SINGLE Cost: 1 Bytes: 16 Cardinality: 1 Partition #: 38
                         36 TABLE ACCESS BY LOCAL INDEX ROWID TABLE XLA.XLA_EVENTS Cost: 1 Bytes: 16 Cardinality: 1 Partition #: 39 Partitions accessed #2
                              35 INDEX UNIQUE SCAN INDEX (UNIQUE) XLA.XLA_EVENTS_U1 Cost: 1 Cardinality: 1 Partition #: 40 Partitions accessed #2
               41 PARTITION LIST SINGLE Cost: 1 Bytes: 15 Cardinality: 1 Partition #: 41
                    40 TABLE ACCESS BY LOCAL INDEX ROWID TABLE XLA.XLA_TRANSACTION_ENTITIES Cost: 1 Bytes: 15 Cardinality: 1 Partition #: 42 Partitions accessed #2
                         39 INDEX UNIQUE SCAN INDEX (UNIQUE) XLA.XLA_TRANSACTION_ENTITIES_U1 Cost: 1 Cardinality: 1 Partition #: 43 Partitions accessed #2
          44 TABLE ACCESS BY INDEX ROWID TABLE GL.GL_CODE_COMBINATIONS Cost: 1 Bytes: 11 Cardinality: 1
               43 INDEX UNIQUE SCAN INDEX (UNIQUE) GL.GL_CODE_COMBINATIONS_U1 Cost: 1 Cardinality: 1

damorgan wrote:
Tuning is NOT about reducing the cost of i/o.
i/o is only one of many contributors to cost and only one of many contributors to waits.
Any time you would like to explore this further run this code:
SELECT 1 FROM dual
WHERE regexp_like(' ','^*[ ]*a');but not on a production box because you are going to experience an extreme tuning event with zero i/o.
And when I say "extreme" I mean "EXTREME!"
You've been warned.I think you just need a faster server.
SQL> set autotrace traceonly statistics
SQL> set timing on
SQL> select 1 from dual
2 where
3 regexp_like   (' ','^*[ ]*a');
no rows selected
Elapsed: 00:00:00.00
Statistics
          1 recursive calls
          0 db block gets
          0 consistent gets
          0 physical reads
          0 redo size
        243 bytes sent via SQL*Net to client
        349 bytes received via SQL*Net from client
          1 SQL*Net roundtrips to/from client
          0 sorts (memory)
          0 sorts (disk)
          0 rows processedRepeated from an Oracle 10.2.0.x instance:
SQL> SELECT DISTINCT SID FROM V$MYSTAT;
       SID
       310
SQL> ALTER SESSION SET EVENTS '10053 TRACE NAME CONTEXT FOREVER, LEVEL 1';
Session altered.
SQL> select 1 from dual
2 where
3 regexp_like   (' ','^*[ ]*a');The session is hung. Wait a little while and connect to the database using a different session:
COLUMN STAT_NAME FORMAT A35 TRU
SET PAGESIZE 200
SELECT
STAT_NAME,
VALUE
FROM
V$SESS_TIME_MODEL
WHERE
SID=310;
STAT_NAME                                VALUE
DB time                                   9247
DB CPU                                    9247
background elapsed time                      0
background cpu time                          0
sequence load elapsed time                   0
parse time elapsed                        6374
hard parse elapsed time                   5997
sql execute elapsed time                  2939
connection management call elapsed        1660
failed parse elapsed time                    0
failed parse (out of shared memory)          0
hard parse (sharing criteria) elaps          0
hard parse (bind mismatch) elapsed           0
PL/SQL execution elapsed time               95
inbound PL/SQL rpc elapsed time              0
PL/SQL compilation elapsed time              0
Java execution elapsed time                  0
repeated bind elapsed time                  48
RMAN cpu time (backup/restore)               0Seems to be using a bit of time for the hard parse (hard parse elapsed time). Wait a little while, then re-execute the query:
STAT_NAME                                VALUE
DB time                                   9247
DB CPU                                    9247
background elapsed time                      0
background cpu time                          0
sequence load elapsed time                   0
parse time elapsed                        6374
hard parse elapsed time                   5997
sql execute elapsed time                  2939
connection management call elapsed        1660
failed parse elapsed time                    0
failed parse (out of shared memory)          0
hard parse (sharing criteria) elaps          0
hard parse (bind mismatch) elapsed           0
PL/SQL execution elapsed time               95
inbound PL/SQL rpc elapsed time              0
PL/SQL compilation elapsed time              0
Java execution elapsed time                  0
repeated bind elapsed time                  48
RMAN cpu time (backup/restore)               0The session is not reporting additional CPU usage or parse time.
Let's check one of the session's statistics:
SELECT
SS.VALUE
FROM
V$SESSTAT SS,
V$STATNAME SN
WHERE
SN.NAME='consistent gets'
AND SN.STATISTIC#=SS.STATISTIC#
AND SS.SID=310;
     VALUE
       163Not many consistent gets after 20+ minutes.
Let's take a look at the plan:
SQL> SELECT SQL_ID,CHILD_NUMBER FROM V$SQL WHERE SQL_TEXT LIKE 'select 1 from du
al%';
SQL_ID        CHILD_NUMBER
04mpgrzhsv72w            0
SELECT * FROM TABLE(DBMS_XPLAN.DISPLAY_CURSOR('04mpgrzhsv72w',0,'TYPICAL'))
select 1 from dual where regexp_like   (' ','^*[ ]*a')
NOTE: cannot fetch plan for SQL_ID: 04mpgrzhsv72w, CHILD_NUMBER: 0
      Please verify value of SQL_ID and CHILD_NUMBER;
      It could also be that the plan is no longer in cursor cache (check v$sql_p
lan)No plan...
Let's take a look at the 10053 trace file:
Registered qb: SEL$1 0x19157f38 (PARSER)
signature (): qb_name=SEL$1 nbfros=1 flg=0
    fro(0): flg=4 objn=258 hint_alias="DUAL"@"SEL$1"
Predicate Move-Around (PM)
PM: Considering predicate move-around in SEL$1 (#0).
PM:   Checking validity of predicate move-around in SEL$1 (#0).
CBQT: Validity checks failed for 7uqx4guu04x3g.
CVM: Considering view merge in query block SEL$1 (#0)
CBQT: Validity checks failed for 7uqx4guu04x3g.
Subquery Unnest
SU: Considering subquery unnesting in query block SEL$1 (#0)
Set-Join Conversion (SJC)
SJC: Considering set-join conversion in SEL$1 (#0).
Predicate Move-Around (PM)
PM: Considering predicate move-around in SEL$1 (#0).
PM:   Checking validity of predicate move-around in SEL$1 (#0).
PM:     PM bypassed: Outer query contains no views.
FPD: Considering simple filter push in SEL$1 (#0)
FPD:   Current where clause predicates in SEL$1 (#0) :
          REGEXP_LIKE (' ','^*[ ]*a')
kkogcp: try to generate transitive predicate from check constraints for SEL$1 (#0)
predicates with check contraints: REGEXP_LIKE (' ','^*[ ]*a')
after transitive predicate generation: REGEXP_LIKE (' ','^*[ ]*a')
finally: REGEXP_LIKE (' ','^*[ ]*a')
apadrv-start: call(in-use=592, alloc=16344), compile(in-use=37448, alloc=42256)
kkoqbc-start
            : call(in-use=592, alloc=16344), compile(in-use=38336, alloc=42256)
kkoqbc-subheap (create addr=000000001915C238)Looks like the query never had a chance to start executing - it is still parsing after 20 minutes.
I am not sure that this is a good example - the query either executes very fast, or never has a chance to start executing. But, it might still make your point physical I/O is not always the problem when performance problems are experienced.
Charles Hooper
IT Manager/Oracle DBA
K&M Machine-Fabricating, Inc.

SQL Developer 2.0

I know we don't have a date; however, it would be nice to know some of the features planned for SQL Developer 2.0.

Hello willjamu,
at the [SQL Developer Exchange|http://apex.oracle.com/pls/otn/f?p=42626:37] you can filter the feature requests for "Scheduled for 2.0" and you can visit the [Statement of Direction|http://www.oracle.com/technology/products/database/sql_developer/files/sqldeveloperstatementofdirection.htm] and read the "Plans for the next release"
Regards
Marcus

Explain plan cost

Hi,
I have explain plan a sql using Enterprise manager. What does the cost indicates, if a query is having a cost of 119 and after tuning its cost is 16 what does it indicate. What is the relationship between time taken by a query to run and its cost.
Regards
Raj

Hi, Raj.
<What does the cost indicate.
In theory, the cost indicates how long a query should take if actually run. Small number means fast, bug number means slow. Its just an arbitrary number computed to indicate how long a query should take to run.
In practice, the cost has little meaning especially in 10g. Its becoming common enough for a high cost to actually run faster than a low cost that our DBA group pretty much ignores the cost.
Remember that the cost is computed before the query is actually run, against computed statistics and available system resources. The cost is an guess, and like all guesses is subject to reality checks.
Message was edited by:
riedelme

Explain Plan in SQL Developer 1.5.1

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