Skip navigation.

Development

Planet Hard Drive? Muddled nonsense from Scientific American

FeuerThoughts - Thu, 2015-07-23 07:59
In the August 2015 issue of Scientific American, I came across an article titled "Planet Hard Drive", a "thought experiment" arguing that we can think of Earth as a kind of "hard drive" and "although Earth has an enormous capacity to store information, order is still rare....but the growth of order on Earth also stems from the production of cultural information."

The article is behind a paywall, so I cannot reproduce it here, but if you are a subscriber, here you go.

I find it generally hard to read SciAm these days, as well as many other scientific sources, because of the pervasive species-ism (humans unique, more important than all others) found sadly among scientists.

But this article was, I thought, a real disappointment, coming from SciAm. I sent this letter to the author:

Professor Hidalgo, 
I read your SciAm article with the above title, and I found it scientifically sloppy and offensively tone deaf, given the state of our planet today (specifically the threat of climate change and human-cause extinctions and species degradation). 
You might not read past that initial paragraph but if you do:
Scientifically Sloppy
I am all for interesting “thought experiments”, but it should have a reasonable amount of logical consistency. I think your experiment fails in this regard. 
Specifically, you talk about the growth of order on earth from production of cultural information.
This implies a clear net positive change in order due to our intensely “ordered” products. 
Yet previously, you recognized that there is order (lots of it) in living things. 
And that's where I see a very deep (specie-ist-driven) fallacy: to create our products humans destroy a vast amount of living things and therefore wipe out corresponding enormous amounts of order. 
Vast parts of the rainforest, extinction of entire species, degradation of the ocean, etc., etc., etc. - do you really think that if you even attempted to conceptualize the volume of order sacrificed to build iPhones, you could come out with a net positive growth in order?
I suppose it might be remotely possible - but you don’t even address this trade-off, making your argument incomplete and sloppy. I am very surprised that SciAm did not insist on a more rigorous treatment.
Sdaly, you seem to blithely accept that destruction of life on our planet in order to manifest our culture-as-thought as products. 
Which that brings me to…
Offensively Tone Deaf
Your insistence to see the entire world through a human filter and impose human paradigms onto the rest of the natural world is shocking, giving the growing awareness (especially among the most rational of us, like many scientists).“A tree, for example, is a computer”
“Objects of this kind [manufactured products] are particularly special.”
“Biological cells are finite computers”
“People are also limited, and we transcend our finite compuational capacities by forming social and professional networks.”“Special” “Transcend”
You use words that impute relentlessly positive values to human activity. 
Yet if you do not place humans “above” all others, you could at least say (my changes in bold):
“People are also limited, and we augment our finite compuational capacities by forming social and professional networks. A necessary consequence of this agumentation is the destruction of the computational capacities of billions of other living creatures.
At the very end of your muddled thought experiment, you finally hint at a bigger picture:“The resulting hyperconnected society will present our species with some of the most challenging ethical problems in human history.”Ah, ethics! Finally! Professor Hidalgo will now point out the grave price paid by our planet and co-inhabitants for human's desire for comfort and convenience, but....
No, no. For you, like way too many other humans, all that matters is the human species.“We could lose aspects of our humanity that some of us consider essential: for example, we might cheat death.”Now that would be a real ethical disaster (cheating death) - precisely because it mean accelerated devastation of our planet and non-humans.
But that doesn’t seem to even register in your thinking.
Categories: Development

New APEX Blog

Denes Kubicek - Wed, 2015-07-22 02:33
This is a new blog on APEX. I expect a lots of good stuff there in the future. The last example describes how to modify the Page Designer and move the panes, adjust the layout and simplify the development of an application since accessing element attributes is much easier that way. I think this is worth of looking at and maybe the APEX team considers this as an improvement for the future release.



Categories: Development

A Lot To Listen To

FeuerThoughts - Mon, 2015-07-20 06:40
A Lot To Listen To

Sometimes, if you're lucky,
there is nothing to hearbut the sound of the windblowing through trees.
Now you could say:"That's not much to listen to."Or you could listen...
Listento the rustling, hissing, whispering, sometimes angry soundof thousands of almost silent brushings of leaf against leaf,of feather-light taps of twig striking twig,any single act nothing to hear at allbut when the tree is big enoughand the leaves are numerous enoughand the branches reach out thinner and thinnerpoking out toward the suncarrying leaves to their destiny,
then you might be able to hearthe sound of the windblowing through trees.
It's a lot to listen to,if you can hear it.



Copyright 2015 Steven Feuerstein
Categories: Development

First patch set (5.0.1) released for APEX 5.0

Dimitri Gielis - Thu, 2015-07-16 15:22
I know some people waiting till the first patch set that comes available after a major Oracle APEX release... today you no longer have to wait, APEX 5.0.1 is now available.

In the patch set notes you can read what changed.

If you're still on APEX 4.x you can go immediately to APEX 5.0.1, you only need to download the latest version on OTN.

If you're already on APEX 5.0, you can download the patch set from support.oracle.com, search for patch number 21364820. Applying the patch took less than 5 minutes in my environment.



This patch set updates the Universal Theme too, so don't forget to update your images folder. When you login in APEX after the patch, it will check if you have the correct images folder, if not it will give you an alert. Although I updated the images directory I still got that alert due to browser caching. Refresh your page and it should be ok.

Note that it's important to be on APEX 5.0.1 when you use APEX Office Print - currently available in beta for a select audience, public release end of this month (July 2015). Behind the scenes we use the APEX_JSON and APEX_WEB_SERVICE packages which got an update in APEX 5.0.1.

And finally, there's a nice new D3 chart available in APEX 5.0.1 called "D3 Collapsible Treemap Chart"


Happy upgrading...

Update 18-JUL-2015: there're still a couple of known issues, please read those too and install some patchset exception when necessary.
Categories: Development

Oracle APEX 5.0.1 now available

Patrick Wolf - Thu, 2015-07-16 05:48
Oracle Application Express 5.0.1 is now released and available for download. If you wish to download the full release of Oracle Application Express 5.0.1, you can get it from the Downloads page on OTN. If you have Oracle APEX 5.0.0 … Continue reading →
Categories: Development

APEX 5 - Opening and Closing Modal Window

Denes Kubicek - Wed, 2015-07-15 04:56
This example is showing how to open a Modal Page from any element in your application. It is easy to get it working using some standards like a button or a link in a report. However, it is not 100% clear how to get it working with some other elements which don't have the redirect functionality built in (item, region title, custom links, etc.). This example is also showing how to get the success message displayed on the parent page after closing of the Modal Page.

Categories: Development

Hot Deployment in JDeveloper 12c - Don't Stop/Start Your App

Shay Shmeltzer - Fri, 2015-07-10 15:45

Old habits are hard to get rid off, and I still see long time users of JDeveloper (and also many new users) who are stopping/starting their application on the embedded WebLogic each time that they make a change or addition to their code.

Well you should stop it! (I mean stop stopping the application).

For a while now, JDeveloper has support for hot deployment that means that when you do most of the changes to your code you just need to do save-all followed by a rebuild of your viewController project - and that's it.

You can then go to your browser and reload your page - and the changes will be reflected there.  This will not only save you the time it takes to undeploy and redeploy your app, it will also reduce the amount of memory you use since frequent redeployment of the app on the embedded WebLogic leads to bigger memory consumption.

In the demo below I use JDeveloper 12.1.3 to show you that I can just do the save->rebuild and pick up:

  • Changes in the JSF file
  • Changes to the JSF configuration file adfc-config.xml
  • New classes that are added to both the model and viewController projects
  • Changed to the ADF configuration files (pagedefs, data binding, data controls)

So for most cases, you should be covered with this hot-deployment capability.

There are some cases that will require a redeploy of the application (for example if you add a new skin css file, or if you change some runtime configuration of your app in web.xml) but for most cases you don't need to continue with the stop/start habit.

Categories: Development

12c: New SQL PLAN OPERATIONS and HINTS

XTended Oracle SQL - Wed, 2015-07-08 07:27

This post is just a compilation of the links to other people’s articles and short descriptions about new SQL PLAN OPERATIONS and HINTS with a couple little additions from me.

th.c_operation_name { min-width:100px; max-width:100px; } th.c_description { min-width:200px } .c_links { min-width:150px; max-width:220px; } .c_links ul { margin: 0 0 5px 0 !important; -webkit-padding-start: 5px; } .c_links ul li { margin-left: 0px; -webkit-padding-start: 0px; } td.c_operation_name { font-size:12px;} td.c_description { font-size:12px;} td.c_links { font-size:10px;} .c_body td { vertical-align: text-top; } div.hints_wrapper { border-style: solid; border-width: 1px; padding: 2px; overflow: scroll !important; } div.hints_content { width: 1175px; min-width:1175px; padding: 2px; }


OPERATION_NAME Description Links JSONTABLE EVALUATION JSON_TABLE execution XMLTABLE EVALUATION This is new name for “COLLECTION ITERATOR PICKLER FETCH [XQSEQUENCEFROMXMLTYPE]”. XPATH EVALUATION still exists. MATCH RECOGNIZE New feature “PATTERN MATCHING” STATISTICS COLLECTOR Optimizer statistics collector OPTIMIZER STATISTICS GATHERING Automatic Optimizer statistics gathering during the following types of bulk loads:

  • CREATE TABLE … AS SELECT
  • INSERT INTO … SELECT into an empty table using a direct-path insert
CUBE JOIN Joining Cubes to Tables and Views EXPRESSION EVALUATION Each parallel slave executes scalar correllated subqueries from SELECT-list. parallel “FILTER” Each parallel slave executes own FILTER operation

Example
SQL> explain plan for
  2  select--+ parallel
  3      owner,object_name
  4  from xt_test l
  5  where exists(select/*+ no_unnest */ 0 from dual where dummy=object_name);

Explained.

PLAN_TABLE_OUTPUT
-------------------------------------------------------------------------------------------------------
Plan hash value: 2189761709

-------------------------------------------------------------------------------------------------------
| Id  | Operation                | Name      | Rows  | Bytes | Cost (%CPU)|   TQ  |IN-OUT| PQ Distrib |
-------------------------------------------------------------------------------------------------------
|   0 | SELECT STATEMENT         |           |     2 |    62 |   177K  (1)|       |      |            |
|   1 |  PX COORDINATOR          |           |       |       |            |       |      |            |
|   2 |   PX SEND QC (RANDOM)    | :TQ10000  | 91060 |  2756K|   113   (0)| Q1,00 | P->S | QC (RAND)  |
|*  3 |    FILTER                |           |       |       |            | Q1,00 | PCWC |            |
|   4 |     PX BLOCK ITERATOR    |           | 91060 |  2756K|   113   (0)| Q1,00 | PCWC |            |
|   5 |      INDEX FAST FULL SCAN| IX_TEST_1 | 91060 |  2756K|   113   (0)| Q1,00 | PCWP |            |
|*  6 |     TABLE ACCESS FULL    | DUAL      |     1 |     2 |     2   (0)|       |      |            |
-------------------------------------------------------------------------------------------------------

Predicate Information (identified by operation id):
---------------------------------------------------

   3 - filter( EXISTS (SELECT /*+ NO_UNNEST */ 0 FROM "SYS"."DUAL" "DUAL" WHERE "DUMMY"=:B1))
   6 - filter("DUMMY"=:B1)
                

[collapse]

PX SELECTOR Execution of the serial plan parts in the one of the parallel slaves PX SEND 1 SLAVE Execution of the serial plan parts in the one of the parallel slaves(single DFO tree) PX TASK Parallel access to fixed tables(x$) by each node in RAC HYBRID HASH DISTRIBUTION Adaptive parallel data distribution that does not decide the final data distribution(HASH, BROADCAST or SKEW) method until execution time. PQ_DISTRIBUTE_WINDOW In addition to “PX SEND” HASH-distribution for WINDOW functions, “PX SEND RANGE” was added
Example
-- TESTPART - list-partitiioned table:
-------------------------------------------------------------------------------------------------
| Operation               | Name     | Rows  | Cost | Pstart| Pstop |   TQ  |IN-OUT| PQ Distrib |
-------------------------------------------------------------------------------------------------
| SELECT STATEMENT        |          | 74384 |   102|       |       |       |      |            |
|  PX COORDINATOR         |          |       |      |       |       |       |      |            |
|   PX SEND QC (RANDOM)   | :TQ10001 | 74384 |   102|       |       | Q1,01 | P->S | QC (RAND)  |
|    WINDOW SORT          |          | 74384 |   102|       |       | Q1,01 | PCWP |            |
|     PX RECEIVE          |          | 74384 |   100|       |       | Q1,01 | PCWP |            |
|      PX SEND RANGE      | :TQ10000 | 74384 |   100|       |       | Q1,00 | P->P | RANGE      |
|       PX BLOCK ITERATOR |          | 74384 |   100|     1 |     3 | Q1,00 | PCWC |            |
|        TABLE ACCESS FULL| TESTPART | 74384 |   100|     1 |     3 | Q1,00 | PCWP |            |
-------------------------------------------------------------------------------------------------
Outline Data
-------------
  /*+
      BEGIN_OUTLINE_DATA
      PQ_DISTRIBUTE_WINDOW(@"SEL$1" 3)
      FULL(@"SEL$1" “TESTPART"@"SEL$1")
      OUTLINE_LEAF(@"SEL$1")
      ALL_ROWS
      DB_VERSION('12.1.0.2')
      OPTIMIZER_FEATURES_ENABLE('12.1.0.2')
      IGNORE_OPTIM_EMBEDDED_HINTS
      END_OUTLINE_DATA
  */

[collapse]
Hint PQ_DISTRIBUTE_WINDOW(@Query_block N), where N=1 for hash, N=2 for range, N=3 for list VECTOR
KEY VECTOR Inmemory aggregation

RECURSIVE ITERATION Unknown WINDOW CONSOLIDATOR WINDOW CONSOLIDATOR BUFFER for parallel execution of analyrical WINDOW aggregation functions

Example
SQL> explain plan for select/*+ parallel(t 4) PQ_DISTRIBUTE_WINDOW(2) */ count(*) over(partition by owner) cnt,owner from xt_test t;
PLAN_TABLE_OUTPUT
---------------------------------------------------------------------------------------------------
Plan hash value: 3410952625
---------------------------------------------------------------------------------------------------
| Id | Operation                    |Name    |Rows |Cost |Pstart|Pstop|   TQ  |IN-OUT| PQ Distrib |
---------------------------------------------------------------------------------------------------
|  0 | SELECT STATEMENT             |        |91060|  124|      |     |       |      |            |
|  1 |  PX COORDINATOR              |        |     |     |      |     |       |      |            |
|  2 |   PX SEND QC (RANDOM)        |:TQ10001|91060|  124|      |     | Q1,01 | P->S | QC (RAND)  |
|  3 |    WINDOW CONSOLIDATOR BUFFER|        |91060|  124|      |     | Q1,01 | PCWP |            |
|  4 |     PX RECEIVE               |        |91060|  124|      |     | Q1,01 | PCWP |            |
|  5 |      PX SEND HASH            |:TQ10000|91060|  124|      |     | Q1,00 | P->P | HASH       |
|  6 |       WINDOW SORT            |        |91060|  124|      |     | Q1,00 | PCWP |            |
|  7 |        PX BLOCK ITERATOR     |        |91060|  122|    1 |    4| Q1,00 | PCWC |            |
|  8 |         TABLE ACCESS FULL    |XT_TEST |91060|  122|    1 |    4| Q1,00 | PCWP |            |
---------------------------------------------------------------------------------------------------

Note
-----
   - Degree of Parallelism is 4 because of table property
                

[collapse] DETECT END Unknown DM EXP MAX AGGR Unknown DM EXP MAX PAR Unknown FAULT-TOLERANCE BUFFER The fault-tolerance for parallel statement.
Patent #US8572051: Making parallel execution of structured query language statements fault-tolerant

  • PX_FAULT_TOLERANCE / NO_PX_FAULT_TOLERANCE hints


See also:

  1. Randolf Geist “12c New Optimizer Features”
  2. Randolf Geist “Parallel Execution 12c New Features Overview”


HINTS:

sup {color: red} table.HINTS{ font-size:12px; } .HINTS td {vertical-align: text-top;}

PATH HINT_CLASS HINT_NAME VERSION VERSION_OUTLINE ALL WITH_PLSQL WITH_PLSQL 12.1.0.1 ALL -> ANSI_REARCH ANSI_REARCH 1 ANSI_REARCH
NO_ANSI_REARCH 12.1.0.2 12.1.0.2 ALL -> EXECUTION BATCH_TABLE_ACCESS_BY_ROWID 2 BATCH_TABLE_ACCESS_BY_ROWID
NO_BATCH_TABLE_ACCESS_BY_ROWID 12.1.0.1 12.1.0.1 INMEMORY INMEMORY
NO_INMEMORY 12.1.0.2 12.1.0.2 INMEMORY_PRUNING INMEMORY_PRUNING
NO_INMEMORY_PRUNING 12.1.0.2 12.1.0.2 ALL -> COMPILATION -> ZONEMAP ZONEMAP ZONEMAP
NO_ZONEMAP 12.1.0.1 12.1.0.1 ALL -> COMPILATION -> DATA_SECURITY_REWRITE DATA_SECURITY_REWRITE_LIMIT DATA_SECURITY_REWRITE_LIMIT

NO_DATA_SECURITY_REWRITE 12.1.0.1 12.1.0.1 ALL -> COMPILATION -> CBO CLUSTER_BY_ROWID CLUSTER_BY_ROWID
CLUSTER_BY_ROWID 12.1.0.1(11.2.0.4) 12.1.0.1 ALL -> COMPILATION -> CBO -> ACCESS_PATH -> BITMAP_TREE BITMAP_AND BITMAP_AND 12.1.0.1 12.1.0.1 ALL -> COMPILATION -> CBO -> ADAPTIVE_PLAN ADAPTIVE_PLAN ADAPTIVE_PLAN
NO_ADAPTIVE_PLAN 12.1.0.2 12.1.0.2 ALL -> COMPILATION -> CBO -> AUTO_REOPT AUTO_REOPTIMIZE 2 AUTO_REOPTIMIZE
NO_AUTO_REOPTIMIZE 12.1.0.1 ALL -> COMPILATION -> CBO -> JOIN_METHOD ANTIJOIN CUBE_AJ 12.1.0.1 12.1.0.1 SEMIJOIN CUBE_SJ 12.1.0.1 12.1.0.1 ALL -> COMPILATION -> CBO -> JOIN_METHOD -> USE_CUBE JOIN USE_CUBE

NO_USE_CUBE 12.1.0.1 12.1.0.1 ALL -> COMPILATION -> CBO -> PARTIAL_JOIN PARTIAL_JOIN PARTIAL_JOIN
NO_PARTIAL_JOIN 12.1.0.1 12.1.0.1 ALL -> COMPILATION -> CBO -> PARTITION USE_HIDDEN_PARTITIONS USE_HIDDEN_PARTITIONS 12.1.0.1 ALL -> COMPILATION -> CBO -> PQ PARTIAL_ROLLUP_PUSHDOWN PARTIAL_ROLLUP_PUSHDOWN

NO_PARTIAL_ROLLUP_PUSHDOWN 12.1.0.1 12.1.0.1 PQ_CONCURRENT_UNION PQ_CONCURRENT_UNION

NO_PQ_CONCURRENT_UNION 12.1.0.1 12.1.0.1 PQ_DISTRIBUTE_WINDOW PQ_DISTRIBUTE_WINDOW 12.1.0.1 12.1.0.1 PQ_FILTER PQ_FILTER 12.1.0.1 12.1.0.1 PQ_SKEW PQ_SKEW

NO_PQ_SKEW 12.1.0.1 12.1.0.1 PX_FAULT_TOLERANCE PX_FAULT_TOLERANCE
NO_PX_FAULT_TOLERANCE 12.1.0.1 12.1.0.1 ALL -> COMPILATION -> CBO -> PQ -> PQ_REPLICATE PQ_REPLICATE PQ_REPLICATE
NO_PQ_REPLICATE 12.1.0.1 12.1.0.1 ALL -> COMPILATION -> CBO -> STATS -> DBMS_STATS GATHER_OPTIMIZER_STATISTICS GATHER_OPTIMIZER_STATISTICS

NO_GATHER_OPTIMIZER_STATISTICS 12.1.0.1 ALL -> COMPILATION -> TRANSFORMATION ELIM_GROUPBY ? ELIM_GROUPBY

NO_ELIM_GROUPBY ALL -> COMPILATION -> CBO -> CBQT -> VECTOR_AGG
and

ALL -> COMPILATION -> TRANSFORMATION -> CBQT -> VECTOR_AGG USE_VECTOR_AGGREGATION USE_VECTOR_AGGREGATION
NO_USE_VECTOR_AGGREGATION 12.1.0.2 12.1.0.2 VECTOR_TRANSFORM VECTOR_TRANSFORM

NO_VECTOR_TRANSFORM 12.1.0.2 12.1.0.2 VECTOR_TRANSFORM_DIMS VECTOR_TRANSFORM_DIMS

NO_VECTOR_TRANSFORM_DIMS 12.1.0.2 12.1.0.2 VECTOR_TRANSFORM_FACT VECTOR_TRANSFORM_FACT

NO_VECTOR_TRANSFORM_FACT 12.1.0.2 12.1.0.2

ALL -> COMPILATION -> TRANSFORMATION -> HEURISTIC -> DECORRELATE DECORRELATE DECORRELATE

NO_DECORRELATE 12.1.0.1 12.1.0.1

See also:
Fuyuncat(Wei Huang) – “Oracle 12c new SQL Hints”

Categories: Development

APEX 5.0 New Features Training September 2015

Denes Kubicek - Wed, 2015-07-08 06:12




Oracle Application Express 5.0 wurde am 15.04.2015 freigegeben und ist als Download verfügbar.

Wir haben jetzt alle über zwei Jahre auf das neue Release gewartet ... und das Warten hat sich mehr als gelohnt ... die neuen Möglichkeiten werden Sie umhauen!

Wir haben die neuen Möglichkeiten genau unter die Lupe genommen und sind selbst total begeistert, weil sie das tägliche Arbeiten extrem vereinfachen. Wir haben schon einige Anwendungen in APEX 5.0 neu programmiert und einige ältere Versionan auf 5.0 umgestellt.

Mit dem neuen Pagedesigner sind wir so produktiv wie noch nie, das Universal Theme erlaubt auf einfache Weise, richtig elegante Applikationen zu entwickeln. Damit ist wirklich ein Durchbruch gelungen, die Konfiguration (über Template Optionen) und selbst farbliche Anpassungen sind ein Kinderspiel, der integrierte Theme Roller ist einfach genial!

Modale Dialoge, multiple Interaktive Berichte pro Seite, Erweiterungen für die mobilen Endgeräte, ein komplett neues File-Handling und viele neue Security - Features ... dieses Release ist wirklich umfangreich!

Neben diesen großen Features wurden auch wieder über 100 kleinere oder auch größere Verbesserungen implementiert.

In unseren Kursen haben wir schon über 200 APEX-Fans die besten Herangehensweisen, Tipps und Tricks beigebracht. Durch die Hands-On Übungen vertiefen wir diese und Sie können diese sofort einsetzen ... oder Sie schlagen sie nach ... wenn Sie sie später brauchen ;). Aber auf jeden Fall wissen Sie nach dem Kurs, was möglich ist!

Wir beide (Denes und Dietmar) entwickeln seit 2006 fast jeden Tag mit APEX Applikationen für unsere Kunden, wir haben mit APEX schon alles ausprobiert.

Nehmen Sie die Abkürzung und lernen Sie von den Besten, was für die Praxis am wichtigsten sein wird.

Um die Vorteile des neuen Releases möglichst schnell nutzen zu können, melden Sie sich am besten sofort an und sichern Sie sich Ihren Platz!
  • Klicken Sie auf den Link "Anmeldung zum Kurs".
  • Tragen Sie Ihre Anmeldedaten ein und klicken Sie auf den Button "Anmelden".
  • Sie bekommen sofort eine Bestätigungs-Email zugeschickt.
  • Sobald Sie in der Email auf den Link zur Bestätigung klicken, haben Sie Ihren Platz gesichert und sind auf jeden Fall dabei!


Anmeldung zum Kurs

P.S.: Die vollständige Agenda und weitere Infos zum Kurs gibt es online in der Kursbeschreibung.
Categories: Development

RESULT_CACHE: run-time dependency tracking

XTended Oracle SQL - Sun, 2015-07-05 13:20

As you know, since 11.2 “relies_on” clause was deprecated and oracle tracks dependencies at runtime now.
Test function and tables

create or replace function f_without_deps(p_tab varchar2) return varchar2
as
   res varchar2(30);
begin
   execute immediate 'select '''||p_tab||''' from '||p_tab||' where rownum=1' into res;
   return res;
end;
/
create table a as select 'a' a from dual;
create table b as select 'b' b from dual;
create view v_ab as select a,b from a,b;

[collapse]
And it works fine with normal tables:
v_ab

SQL> exec :p_tab:='v_ab';

PL/SQL procedure successfully completed.

SQL> call DBMS_RESULT_CACHE.flush();

Call completed.

SQL> select/*+ result_cache */ f_without_deps(:p_tab) result from dual;

RESULT
----------
v_ab

1 row selected.

SQL> select name,bucket_no, id,type,status,pin_count,scan_count,invalidations from v$result_cache_objects o order by type,id;

NAME                                                               BUCKET_NO  ID TYPE       STATUS     PIN_COUNT SCAN_COUNT INVALID
----------------------------------------------------------------- ---------- --- ---------- --------- ---------- ---------- -------
XTENDER.F_WITHOUT_DEPS                                                  1579   0 Dependency Published          0          0       0
XTENDER.V_AB                                                            3127   2 Dependency Published          0          0       0
XTENDER.B                                                                778   3 Dependency Published          0          0       0
XTENDER.A                                                                464   4 Dependency Published          0          0       0
select/*+ result_cache */ f_without_deps(:p_tab) result from dual       1749   1 Result     Published          0          0       0

[collapse]
But don’t forget that the result_cache also caches such functions with the objects, that usually should not be cached, and such objects will not be listed in the result_cache dependencies list:
v$database

SQL> exec :p_tab:='v$database';

PL/SQL procedure successfully completed.

SQL> call DBMS_RESULT_CACHE.flush();

Call completed.

SQL> select/*+ result_cache */ f_without_deps(:p_tab) result from dual;

RESULT
----------
v$database

1 row selected.

SQL> select name,bucket_no, id,type,status,pin_count,scan_count,invalidations from v$result_cache_objects o order by type,id;

NAME                                                               BUCKET_NO  ID TYPE       STATUS     PIN_COUNT SCAN_COUNT INVALID
----------------------------------------------------------------- ---------- --- ---------- --------- ---------- ---------- -------
XTENDER.F_WITHOUT_DEPS                                                   772   0 Dependency Published          0          0       0
PUBLIC.V$DATABASE                                                       1363   2 Dependency Published          0          0       0
select/*+ result_cache */ f_without_deps(:p_tab) result from dual       2283   1 Result     Published          0          0       0

3 rows selected.

[collapse] As you can see, there is only dependency on public synonym V$DATABASE, but not real base fixed X$-tables.
SYS.OBJ$

SQL> exec :p_tab:='sys.obj$';

PL/SQL procedure successfully completed.

SQL> call DBMS_RESULT_CACHE.flush();

Call completed.

SQL> select/*+ result_cache */ f_without_deps(:p_tab) result from dual;

RESULT
----------
sys.obj$

1 row selected.

SQL> select name,bucket_no, id,type,status,pin_count,scan_count,invalidations from v$result_cache_objects o order by type,id;

NAME                                                               BUCKET_NO ID TYPE       STATUS     PIN_COUNT SCAN_COUNT INVALID
----------------------------------------------------------------- ---------- -- ---------- --------- ---------- ---------- -------
XTENDER.F_WITHOUT_DEPS                                                  3922  0 Dependency Published          0          0       0
select/*+ result_cache */ f_without_deps(:p_tab) result from dual       3753  1 Result     Published          0          0       0

2 rows selected.

[collapse] The results were cached and the dependencies do not include system objects.
We easily check that the queries with any table in SYS schema or with sysdate,systimestamp,current_date,current_timestamp,dbms_random will not be cached:
SYS tables

SQL> select/*+ result_cache */ current_scn result from v$database;

    RESULT
----------
##########

1 row selected.

SQL> select name,bucket_no, id,type,status,pin_count,scan_count,invalidations from v$result_cache_objects o order by type,id;

no rows selected

SQL> explain plan for select/*+ result_cache */ * from sys.obj$;

PLAN_TABLE_OUTPUT
--------------------------------------------------------------------------
Plan hash value: 2311451600

--------------------------------------------------------------------------
| Id  | Operation         | Name | Rows  | Bytes | Cost (%CPU)| Time     |
--------------------------------------------------------------------------
|   0 | SELECT STATEMENT  |      | 87256 |  7328K|   296   (1)| 00:00:04 |
|   1 |  TABLE ACCESS FULL| OBJ$ | 87256 |  7328K|   296   (1)| 00:00:04 |
--------------------------------------------------------------------------

[collapse] Note that there is no “RESULT CACHE” line.
And even if create own tables in SYS schema(don’t do it :)), they will not be cached :
SYS.V_AB

SYS> create table a as select 'a' a from dual;
SYS> create table b as select 'b' b from dual;
SYS> create view v_ab as select a,b from a,b;
SYS> grant select on v_ab to xtender;

XTENDER> explain plan for select/*+ result_cache */ * from sys.v_ab;
PLAN_TABLE_OUTPUT
-----------------------------------------------------------------------------
Plan hash value: 215283502

-----------------------------------------------------------------------------
| Id  | Operation            | Name | Rows  | Bytes | Cost (%CPU)| Time     |
-----------------------------------------------------------------------------
|   0 | SELECT STATEMENT     |      |     1 |     6 |     4   (0)| 00:00:01 |
|   1 |  MERGE JOIN CARTESIAN|      |     1 |     6 |     4   (0)| 00:00:01 |
|   2 |   TABLE ACCESS FULL  | A    |     1 |     3 |     2   (0)| 00:00:01 |
|   3 |   BUFFER SORT        |      |     1 |     3 |     2   (0)| 00:00:01 |
|   4 |    TABLE ACCESS FULL | B    |     1 |     3 |     2   (0)| 00:00:01 |
-----------------------------------------------------------------------------

Note
-----
   - dynamic sampling used for this statement (level=2)

[collapse]
But sys_context and userenv will be cached successbully:
sys_context

SQL> explain plan for select/*+ result_cache */ sys_context('userenv','os_user')  from dual;

PLAN_TABLE_OUTPUT
---------------------------------------------------------------------------------------
Plan hash value: 1388734953

---------------------------------------------------------------------------------------
| Id  | Operation        | Name                       | Rows  | Cost (%CPU)| Time     |
---------------------------------------------------------------------------------------
|   0 | SELECT STATEMENT |                            |     1 |     2   (0)| 00:00:01 |
|   1 |  RESULT CACHE    | 267m2hcwj08nq5kwxcb0nb2ka8 |       |            |          |
|   2 |   FAST DUAL      |                            |     1 |     2   (0)| 00:00:01 |
---------------------------------------------------------------------------------------

Result Cache Information (identified by operation id):
------------------------------------------------------

   1 - column-count=1; attributes=(single-row); parameters=(sys_context);
        name="select/*+ result_cache */ sys_context('userenv','os_user')  from dual"

14 rows selected.

[collapse] userenv

SQL> explain plan for select/*+ result_cache */ userenv('instance')  from dual;

PLAN_TABLE_OUTPUT
---------------------------------------------------------------------------------------
Plan hash value: 1388734953

---------------------------------------------------------------------------------------
| Id  | Operation        | Name                       | Rows  | Cost (%CPU)| Time     |
---------------------------------------------------------------------------------------
|   0 | SELECT STATEMENT |                            |     1 |     2   (0)| 00:00:01 |
|   1 |  RESULT CACHE    | dxzj3fks1sqfy35shbbst4332h |       |            |          |
|   2 |   FAST DUAL      |                            |     1 |     2   (0)| 00:00:01 |
---------------------------------------------------------------------------------------

Result Cache Information (identified by operation id):
------------------------------------------------------

   1 - column-count=1; attributes=(single-row); parameters=(sys_context); 
       name="select/*+ result_cache */ userenv('instance')  from dual"

[collapse]

Categories: Development

A function gets called twice if the result_cache is used

XTended Oracle SQL - Sun, 2015-07-05 07:37

Recently I showed simple example how result_cache works with non-deterministic functions and observed strange behaviour: a function gets fired once in the normal query, but twice with the result_cache hint.
Moreover, only third and subsequent query executions return same cached results as second query execution.
I didn’t want to investigate such behavior, just because 1) we should not cache the results of non-deterministic functions and 2) it doesn’t matter if we use deterministic functions.
But later I was asked to explain this, so this post is just a short description with test case.

Look at the simple function that just returns random values:

create or replace function f_nondeterministic(p int:=100) return int
as
  res number;
begin
   res:=round(dbms_random.value(0,p));
   return res;
end;
SQL> exec dbms_result_cache.flush;
PL/SQL procedure successfully completed.

SQL> select/*+ result_cache */ f_nondeterministic(1000) nondeter from dual;

  NONDETER
----------
       481

SQL> select/*+ result_cache */ f_nondeterministic(1000) nondeter from dual;

  NONDETER
----------
       689

SQL> select/*+ result_cache */ f_nondeterministic(1000) nondeter from dual;

  NONDETER
----------
       689

with result_cache_statistics

SQL> exec dbms_result_cache.flush;

PL/SQL procedure successfully completed.

SQL> select/*+ result_cache */ f_nondeterministic(1000) nondeter from dual;

  NONDETER
----------
       481

SQL> select name,value from v$result_cache_statistics where name in ( 'Create Count Success', 'Find Count');

NAME                                               VALUE
-------------------------------------------------- ----------
Create Count Success                               1
Find Count                                         0

SQL> select/*+ result_cache */ f_nondeterministic(1000) nondeter from dual;

  NONDETER
----------
       689

SQL> select name,value from v$result_cache_statistics where name in ( 'Create Count Success', 'Find Count');

NAME                                               VALUE
-------------------------------------------------- ----------
Create Count Success                               1
Find Count                                         1

SQL> select/*+ result_cache */ f_nondeterministic(1000) nondeter from dual;

  NONDETER
----------
       689

SQL> select name,value from v$result_cache_statistics where name in ( 'Create Count Success', 'Find Count');

NAME                                               VALUE
-------------------------------------------------- ----------
Create Count Success                               1
Find Count                                         2

SQL> select name,bucket_no, id,type,status,pin_count,scan_count,invalidations from v$result_cache_objects o;

NAME                                                BUCKET_NO         ID TYPE       STATUS     PIN_COUNT SCAN_COUNT INVALIDATIONS
-------------------------------------------------- ---------- ---------- ---------- --------- ---------- ---------- -------------
XTENDER.F_NONDETERMINISTIC                                552          0 Dependency Published          0          0             0
select/*+ result_cache */ f_nondeterministic(1000)       2102          1 Result     Published          0          2             0
 nondeter from dual

[collapse]
As you can see, second execution returns different result than first one.
If we change this function:

create or replace function f_nondeterministic(p int:=100) return int
as
  res number;
begin
   res:=round(dbms_random.value(0,p));
   dbms_output.put_line('fired! ('||res||')');
   return res;
end;

and repeat this test-case:

SQL> select/*+ result_cache */ f_nondeterministic(1000) nondeter from dual;

  NONDETER
----------
       943    -- << (2)

1 row selected.

fired! (607)    -- << (1)
fired! (943)    -- << (2)
SQL> /

  NONDETER
----------
       607    -- << (1)

1 row selected.

SQL> /

  NONDETER
----------
       607    -- << (1)

1 row selected.

SQL> /

  NONDETER
----------
       607    -- << (1)

1 row selected.

we will see that there were 2 function executions: first result was cached, and the second was fetched!

Categories: Development

Introducing Formspider 1.9

Gerger Consulting - Thu, 2015-07-02 01:35
For the past year, we've been working hard on the new version of Formspider, the application development tool for Oracle PL/SQL Developers. Join our special virtual event on July 7th and become one of the first people who'll find out what we have in store for you.Whether you are an IT Manager trying to modernize your legacy software, an Oracle Forms Developer looking for a new development tool that is suitable to your skill set, a  PL/SQL Developer searching for a great way to build web applications or an APEX Developer who thinks that there must be a better solution, we'll have something for you.See you on July 7th.Kind Regards,
Yalim K. Gerger
Founder
Categories: Development

Make even more of UKOUG Tech15: APEX 5.0 UI Training - Dec 10th in Birmingham

Dimitri Gielis - Tue, 2015-06-30 00:48

APEX 5.0 has been released this spring. People who have already spent some time on this new version know this version is packed with new features aimed to make APEX developers even more productive, like the Page Designer.
Another striking new subset of features is aimed at creating better looking user interfaces for your APEX applications in an easy and maintainable way. The definition of user interface components in APEX 5.0 is very different to what we're used to. For example there is a new Universal Theme with Template Options and a Theme Roller. To get you up and running with this new toolset as quickly as possible, Dimitri Gielis of APEX R&D and Roel Hartman of APEX Consulting have joined forces and set up a one day course fully aimed at APEX 5.0 UI. So if you want to know not only how to use the new Theme, but also how to modify it to fit your needs, this is the event you should attend!
The training will be at the Jury’s Inn in Birmingham (UK) on Thursday Dec 10 - so conveniently immediately after the UKOUG Tech15 conference.More information and registration see www.apextraining.eu
If you are from another country and think this training should be available in your country as well, please contact us - then we'll see what we can do!
Categories: Development

SQL*Plus tips #7: How to find the current script directory

XTended Oracle SQL - Fri, 2015-06-26 13:06

You know that if we want to execute another script from the current script directory, we can call it through @@, but sometimes we want to know the current path exactly, for example if we want to spool something into the file in the same directory.
Unfortunately we cannot use “spool @spoolfile”, but it is easy to find this path, because we know that SQL*Plus shows this path in the error when it can’t to find @@filename.

So we can simply get this path from the error text:

rem Simple example how to get path (@@) of the current script.
rem This script will set "cur_path" variable, so we can use &cur_path later.
 
set termout off
spool _cur_path.remove
@@notfound
spool off;
 
var cur_path varchar2(100);
declare 
  v varchar2(100);
  m varchar2(100):='SP2-0310: unable to open file "';
begin v :=rtrim(ltrim( 
                        q'[
                            @_cur_path.remove
                        ]',' '||chr(10)),' '||chr(10));
  v:=substr(v,instr(v,m)+length(m));
  v:=substr(v,1,instr(v,'notfound.')-1);
  :cur_path:=v;
end;
/
set scan off;
ho (rm _cur_path.remove 2>&1  | echo .)
ho (del _cur_path.remove 2>&1 | echo .)
col cur_path new_val cur_path noprint;
select :cur_path cur_path from dual;
set scan on;
set termout on;
 
prompt Current path: &cur_path

I used here the reading file content into variable, that I already showed in the “SQL*Plus tips. #1″.
UPDATE: I’ve replaced this script with a cross platform version.

Also I did it with SED and rtrim+ltrim, because 1) I have sed even on windows; and 2) I’m too lazy to write big PL/SQL script that will support 9i-12c, i.e. without regexp_substr/regexp_replace, etc.
But of course you can rewrite it without depending on sed, if you use windows without cygwin.

PS. Note that “host pwd” returns only directory where SQL*Plus was started, but not executed script directory.

Download latest version

Categories: Development

Quick and Dirty - Refreshing a Select List of Values

Denes Kubicek - Tue, 2015-06-23 05:14
This is a quick and dirty solution but it works. It shows hot to update a select list of values on demand without a lot of coding.

Categories: Development

AJAX Callback and jQuery creating Page Items Dynamically

Denes Kubicek - Tue, 2015-06-23 04:40
This example shows a couple of interesting techniques:
  • 1. How to create and use an AJAX Callback process instead of an Application Process on Demand,
  • 2. how to create a dynamic page item,
  • 3. how to modify the item display settings and reference Font Awsome icon set and finaly,
  • 4. it shows how to call an AJAX process from javascript.
This question is based on a recent forum posting where this question was asked.

Have a look and enjoy.

Categories: Development

Aporias

Greg Pavlik - Sat, 2015-06-20 10:03
1.ActuallyHe likes word games    DiffidentIn the way they circle about    Starlings in flight    Or Seraphim.
2.With sweeping gesture    Left to rightHands hang with headUnder the pressing of the sun:    Weight of doubt    Or will.
3.Against open air, tumultuous sea    Turtle greenThe division is nowhere more evidentWhere sand meets froth    Stark, blinding glareWind balmed    Until night.
4.Cleanliness,    Next to godlinessThe echo of countless schoolmarmsChiding, chilling - without regret    Yeah, rather,    Motherhood.

What The World Needs More Of

Greg Pavlik - Fri, 2015-06-19 14:07
The interview with these two kids - Chris and Camryn Singleton - is available on BBC, but I wanted to pull out this remarkable commentary in a related article:

"People are hurting in Charleston. But for the hundreds who packed into the gymnasium at the Goose Creek High School, it was also a reminder of the importance of love.

Sharonda Singleton coached the girls' athletics team here. As her photo rested on an easel on the polished floors in the vast sports hall, her friends and family paid tribute. Speaking for the first time since the deadly attack on the AME church where she worshipped, Sharonda's two children, Chris and Camryn, told me they forgive the man who killed her.

 "We already forgive him and there's nothing but love from our side of the family," Chris told me.

Many will find this incomprehensible. Charleston is often called the Holy City for the number of churches it is home to, and the role religion plays here. For some, like Chris and Camryn, unwavering faith is the only way to turn such a devastating loss into something positive."

This immediately brought to mind the sayings of Fr Zosima in Dostoevsky's Brothers Karamazov, which not to many years ago were the source of a kind of epiphany for me that in a sense reoriented by own thinking:

"Strive to love your neighbor actively and indefatigably. In as far as you advance in love you will grow surer of the reality of God and of the immortality of your soul. If you attain to perfect self-forgetfulness in the love of your neighbor, then you will believe without doubt, and no doubt can possibly enter your soul. This has been tried. This is certain.

Above all, avoid falsehood, every kind of falsehood, especially falseness to yourself. Watch over your own deceitfulness and look into it every hour, every minute. Avoid being scornful, both to others and to yourself. What seems to you bad within you will grow purer from the very fact of your observing it in yourself. Avoid fear, too, though fear is only the consequence of every sort of falsehood. Never be frightened at your own faint-heartedness in attaining love. Don't be frightened overmuch even at your evil actions. I am sorry I can say nothing more consoling to you, for love in action is a harsh and dreadful thing compared with love in dreams. Love in dreams is greedy for immediate action, rapidly performed and in the sight of all. Men will even give their lives if only the ordeal does not last long but is soon over, with all looking on and applauding as though on the stage. But active love is labor and fortitude, and for some people too, perhaps, a complete science. But I predict that just when you see with horror that in spite of all your efforts you are getting farther from your goal instead of nearer to it—at that very moment I predict that you will reach it and behold clearly the miraculous power of the Lord who has been all the time loving and mysteriously guiding you."

....

"At some thoughts one stands perplexed, especially at the sight of men's sin, and wonders whether one should use force or humble love. Always decide to use humble love. If you resolve on that once for all, you may subdue the whole world. Loving humility is marvelously strong, the strongest of all things, and there is nothing else like it." 

....
"“Remember particularly that you cannot be a judge of anyone. For no one can judge a criminal until he recognizes that he is just such a criminal as the man standing before him, and that he perhaps is more than all men to blame for that crime. When he understands that, he will be able to be a judge. Though that sounds absurd, it is true. If I had been righteous myself, perhaps there would have been no criminal standing before me. If you can take upon yourself the crime of the criminal your heart is judging, take it at once, suffer for him yourself, and let him go without reproach. And even if the law itself makes you his judge, act in the same spirit so far as possible, for he will go away and condemn himself more bitterly than you have done. If, after your kiss, he goes away untouched, mocking at you, do not let that be a stumbling-block to you. It shows his time has not yet come, but it will come in due course. And if it come not, no matter; if not he, then another in his place will understand and suffer, and judge and condemn himself, and the truth will be fulfilled. Believe that, believe it without doubt; for in that lies all the hope and faith of the saints.”

This time, Chris and Camryn have moved me beyond words by living this reality.

Addendum/edit: more of this humbling love on display