Deterministic function

A function is deterministic if the returned value is completely determined by its entries (arguments).

CN, I get an example for the function deteministic. When exactly can we declare a deterministic function?

Rahul_India wrote:

A function is deterministic if the returned value is completely determined by its entries (arguments).

CN, I get an example for the function deteministic. When exactly can we declare a deterministic function?

A deterministic function basically means that whenever you provide values settings you will always get the same return results (the results are "determined" by the entry and will not change over time)

Might be easier to look at examples of deterministic functions and not deterministic, to better understand...

Non Deterministic - a function that takes an ID of service as a parameter and returns the number of employees in this Department

Non Deterministic - a function that takes no parameters and returns the current date

Deterministic - a function that takes two strings and returns the first characters of the two concatenated

Deterministic - a function that takes two values and applies a non-random mathematical computation before returning the result. adding for example numbers, MOD etc.

Tags: Database

Similar Questions

  • How does a deterministic function caching mechanism works?

    Hi all

    I read an article on caching by Tom Kyte. http://www.Oracle.com/technetwork/issue-archive/2011/11-Sep/o51asktom-453438.html

    In accordance with article the two mechanisms are based on the hash functions. The scalar subquery caching is explained in details. However, there are some questions about the deterministic functions.

    Can someone please explain, if there are 32 different values for the column 'owner' in the table of the scene. So, how is it deterministic function cannot be executed 32 times as well as the function result cache?

    SQL > create or replace function f (x in varchar2)

    Return number

    2 DETERMINISTIC

    3 as

    4 start

    5 dbms_application_info.set_client_info

    (userenv ('client_info') + 1);

    6 return length (x);

    7 end;

    8.

    The function is created.

    SQL > start

    2: cpu: = dbms_utility.get_cpu_time;

    3 dbms_application_info.set_client_info (0);

    4 end;

    5.

    PL/SQL procedure successfully completed.

    SQL > select master, f (owner) of scene;

    ...

    72841 selected lines.

    SQL > select

    2 dbms_utility.get_cpu_time-: cpu cpu_hsecs,.

    3 userenv ('client_info')

    4 double;

    CPU_HSECS USERENV ('CLIENT_INFO')

    ---------   -----------------------

    69                      8316

    SQL > create or replace function f (x in varchar2)

    Return number

    2 RESULT_CACHE

    3 as

    4 start

    5 dbms_application_info.set_client_info

    (userenv ('client_info') + 1);

    6 return length (x);

    7 end;

    8.

    The function is created.

    SQL > start

    2: cpu: = dbms_utility.get_cpu_time;

    3 dbms_application_info.set_client_info (0);

    4 end;

    5.

    PL/SQL procedure successfully completed.

    SQL > select master, f (owner) of scene;

    ...

    72841 selected lines.

    SQL > select

    2 dbms_utility.get_cpu_time-: cpu cpu_hsecs,.

    3 userenv ('client_info')

    4 double;

    CPU_HSECS USERENV ('CLIENT_INFO')

    ---------   -----------------------

    73                        32

    Thanks in advance!

    The deteministic function is deterministic for the duration of a single database call.

    SQL * the 'extraction' is such an appeal, and the arraysize failure means issue you a new call every 15 rows.

    Tests:

    ARRAYSIZE 1 000 1 set) and you should see the County substantially

    (2) set arraysize 33, select master, f (owner), count (*) from the group stage by owner, f (owner); and you should see the number drop to 32 (even if perhaps 33 due to a minor detail of how the extractions begin)

    Interesting documents here: Oracle SQL | A function deterministic vs scalar subquery caching. Part 1 (and follow the links)

    Concerning

    Jonathan Lewis

  • details of the virtual columns and deterministic function

    Hello

    First time that I post a question after the migration of the Forums. So please excuse me if you see errors in format.

    Below, I have created a function as deterministic and a table with a virtual column (column refers to the function)

    Here are my questions

    (1) if I run SELECT * FROM t whenever Oracle will perform the function add_fn?

    (2) what is the advantage of DETERMINISTIC? (Documentation says that if we declare a function as deterministic he will attempt to use previously caluculated results for the same set of values. So, when I ever I run SELECT * FROM t oracle executes add_fn only once and it will use the result for the next time. Is my understanding correct.)

    Here's the code.

    SQL> create or replace function add_fn ( p_n1 in number
  2                                                   ,p_n2 in number )
  3  return number deterministic
  4  is
  5  begin
  6      return p_n1+p_n2;
  7  end;
  8  /
Function created
SQL> create table t ( n1 number
  2                       ,n2 number
  3         ,n3 number generated always as (add_fn(n1,n2)) virtual
  4         );
Table created
SQL> insert into t (n1,n2) values (10,20);
1 row inserted
SQL> select * from t;
        N1         N2         N3
---------- ---------- ----------
        10         20         30
SQL> select * from t;
        N1         N2         N3
---------- ---------- ----------
        10         20         30
SQL>

    Hello

    ...
    (1) if I run SELECT * FROM t whenever Oracle will perform the function add_fn?

    (2) what is the advantage of DETERMINISTIC? (Documentation says that if we declare a function as deterministic he will attempt to use previously caluculated results for the same set of values. So, when I ever I run SELECT * FROM t oracle executes add_fn only once and it will use the result for the next time. Is my understanding correct.)

    ...

    (1) oracle will have to evaluate the function.  Because only deterministic functions are allowed, this means that it will not necessarily perform the function again; He can get the value cached from a previous call.

    I think that the indexed values are actually stored in the index.  "SELECT * FROM t;" do not use an index, but if you make another request, then you should be able to get the value of the virtual table of the index, without calling the function or obtaining the value of a cache.

    (2) If a function is DETERMINISTIC, the optimizer may decide whether to actually call the function each time, or the cache for better performance results.  There is no guarantee that it will always be one or the other.  Replace "will be" in your description "may", and then what you say is correct.

  • NVL and deterministic function

    Hi all
    I recently found a note on deterministic function and its use. As usual check and validate with various relevant articles on the same topic. I decided to check the importance of it with an example below.

      
 create table rnd_all_objects as select * from all_objects;
   
 create or replace function RND_check_null_var(p_var in varchar)
    return varchar2
  deterministic
    as
    begin
       if p_var is null then
          return 'X';
       else
          return p_var;
      end if;
 end;

 create index rnd_DET on rnd_all_objects (rnd_check_null_var(status));

 select COUNT('X') from rnd_all_objects 
 --where status is null  
  where RND_check_null_var(status) = 'X'

 /*
  One can check the plan of the query by commenting the 3rd line of query and uncommenting 2nd line to compare the performance.
 */
    The example given, it seems if we happen to use deterministic functions and replace NVL in where clause if appropriate and possible its picking the index created and the query is very effective. We have tested with more records too. This is to say that the index is selected, even when records are questioned are even more than 90% of all of the data in the table for the given condition, is not happens on a normal basis.

    I pray the pros discuss and get rid of my doubts.

    Thanks in advance.

    Here's what I mean:

    After doing this:

     create index rnd_1 on rnd_all_objects (rnd_check_null_var(status));
 create index rnd_2 on rnd_all_objects (nvl(status,'X'));
 create index rnd_3 on rnd_all_objects (status,'X');

    And then what follows, I see no difference between NVL and deterministic function.

    Connected to:
Oracle Database 11g Enterprise Edition Release 11.2.0.2.0 - 64bit Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options

SQL> set lines 120
SQL> set pages 999
SQL> SELECT *
  2  FROM   rnd_all_objects
  3  WHERE  rnd_check_null_var(status) = 'X';

no rows selected

SQL>
SQL> select * from table(dbms_xplan.display_cursor);

PLAN_TABLE_OUTPUT
----------------------------------------------------------------------------------------------------
SQL_ID  24rfj6nz0haks, child number 0
-------------------------------------
SELECT * FROM   rnd_all_objects WHERE  rnd_check_null_var(status) = 'X'

Plan hash value: 3930105948

-----------------------------------------------------------------------------------------------
| Id  | Operation                   | Name            | Rows  | Bytes | Cost (%CPU)| Time     |
-----------------------------------------------------------------------------------------------
|   0 | SELECT STATEMENT            |                 |       |       |   117 (100)|          |
|   1 |  TABLE ACCESS BY INDEX ROWID| RND_ALL_OBJECTS |   428 |   902K|   117   (0)| 00:00:02 |
|*  2 |   INDEX RANGE SCAN          | RND_1           |   171 |       |   114   (0)| 00:00:02 |
-----------------------------------------------------------------------------------------------

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

   2 - access("RND_ALL_OBJECTS"."SYS_NC00016$"='X')

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

23 rows selected.

SQL>
SQL> SELECT COUNT(*)
  2  FROM   rnd_all_objects
  3  WHERE  rnd_check_null_var(status) = 'X';

  COUNT(*)
----------
         0

SQL>
SQL> select * from table(dbms_xplan.display_cursor);

PLAN_TABLE_OUTPUT
----------------------------------------------------------------------------------------------------
SQL_ID  9pkp2u9xyfd5f, child number 0
-------------------------------------
SELECT COUNT(*) FROM   rnd_all_objects WHERE
rnd_check_null_var(status) = 'X'

Plan hash value: 2866958763

---------------------------------------------------------------------------
| Id  | Operation         | Name  | Rows  | Bytes | Cost (%CPU)| Time     |
---------------------------------------------------------------------------
|   0 | SELECT STATEMENT  |       |       |       |     1 (100)|          |
|   1 |  SORT AGGREGATE   |       |     1 |     6 |            |          |
|*  2 |   INDEX RANGE SCAN| RND_1 |     1 |     6 |     1   (0)| 00:00:01 |
---------------------------------------------------------------------------

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

   2 - access("RND_ALL_OBJECTS"."SYS_NC00016$"='X')

20 rows selected.

SQL>
SQL> SELECT *
  2  FROM   rnd_all_objects
  3  WHERE  nvl(status,'X') = 'X';

no rows selected

SQL>
SQL> select * from table(dbms_xplan.display_cursor);

PLAN_TABLE_OUTPUT
----------------------------------------------------------------------------------------------------
SQL_ID  762n8j14mpqk1, child number 1
-------------------------------------
SELECT * FROM   rnd_all_objects WHERE  nvl(status,'X') = 'X'

Plan hash value: 2211738098

-----------------------------------------------------------------------------------------------
| Id  | Operation                   | Name            | Rows  | Bytes | Cost (%CPU)| Time     |
-----------------------------------------------------------------------------------------------
|   0 | SELECT STATEMENT            |                 |       |       |   117 (100)|          |
|   1 |  TABLE ACCESS BY INDEX ROWID| RND_ALL_OBJECTS |   428 | 69764 |   117   (0)| 00:00:02 |
|*  2 |   INDEX RANGE SCAN          | RND_2           |   171 |       |   114   (0)| 00:00:02 |
-----------------------------------------------------------------------------------------------

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

   2 - access("RND_ALL_OBJECTS"."SYS_NC00017$"='X')

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

23 rows selected.

SQL>
SQL> SELECT COUNT(*)
  2  FROM   rnd_all_objects
  3  WHERE  nvl(status,'X') = 'X';

  COUNT(*)
----------
         0

SQL>
SQL> select * from table(dbms_xplan.display_cursor);

PLAN_TABLE_OUTPUT
----------------------------------------------------------------------------------------------------
SQL_ID  0bhwd0rc3g7pp, child number 0
-------------------------------------
SELECT COUNT(*) FROM   rnd_all_objects WHERE  nvl(status,'X') = 'X'

Plan hash value: 1668065865

---------------------------------------------------------------------------
| Id  | Operation         | Name  | Rows  | Bytes | Cost (%CPU)| Time     |
---------------------------------------------------------------------------
|   0 | SELECT STATEMENT  |       |       |       |     1 (100)|          |
|   1 |  SORT AGGREGATE   |       |     1 |     6 |            |          |
|*  2 |   INDEX RANGE SCAN| RND_2 |     1 |     6 |     1   (0)| 00:00:01 |
---------------------------------------------------------------------------

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

   2 - access("RND_ALL_OBJECTS"."SYS_NC00017$"='X')

19 rows selected.

SQL>
SQL> SELECT *
  2  FROM   rnd_all_objects
  3  WHERE  status is null;

no rows selected

SQL>
SQL> select * from table(dbms_xplan.display_cursor);

PLAN_TABLE_OUTPUT
----------------------------------------------------------------------------------------------------
SQL_ID  b2zw36qjc8nxq, child number 0
-------------------------------------
SELECT * FROM   rnd_all_objects WHERE  status is null

Plan hash value: 2472515261

-----------------------------------------------------------------------------------------------
| Id  | Operation                   | Name            | Rows  | Bytes | Cost (%CPU)| Time     |
-----------------------------------------------------------------------------------------------
|   0 | SELECT STATEMENT            |                 |       |       |    43 (100)|          |
|   1 |  TABLE ACCESS BY INDEX ROWID| RND_ALL_OBJECTS |  2399 |   264K|    43   (0)| 00:00:01 |
|*  2 |   INDEX RANGE SCAN          | RND_3           |  2399 |       |     8   (0)| 00:00:01 |
-----------------------------------------------------------------------------------------------

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

   2 - access("STATUS" IS NULL)

19 rows selected.

SQL>
SQL> SELECT COUNT('X')
  2  FROM   rnd_all_objects
  3  WHERE  status is null;

COUNT('X')
----------
         0

SQL>
SQL> select * from table(dbms_xplan.display_cursor);

PLAN_TABLE_OUTPUT
----------------------------------------------------------------------------------------------------
SQL_ID  03gbx96m8a4hp, child number 0
-------------------------------------
SELECT COUNT('X') FROM   rnd_all_objects WHERE  status is null

Plan hash value: 1659481815

---------------------------------------------------------------------------
| Id  | Operation         | Name  | Rows  | Bytes | Cost (%CPU)| Time     |
---------------------------------------------------------------------------
|   0 | SELECT STATEMENT  |       |       |       |     9 (100)|          |
|   1 |  SORT AGGREGATE   |       |     1 |     5 |            |          |
|*  2 |   INDEX RANGE SCAN| RND_3 |     8 |    40 |     9   (0)| 00:00:01 |
---------------------------------------------------------------------------

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

   2 - access("STATUS" IS NULL)

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

23 rows selected.

    Published by: DomBrooks on November 24, 2010 11:46

  • create indexes on the upper part of the column - reminders function is not deterministic

    Hi all

    I'm having a problem on a database. When you create an index on an existing table on the upper part of a column, Oracle triggers an ORA-30553. I've done this 40 index other databases, with the same and different versions, without problem. When you create the index on a copy of the table, it is created with success...

    Here is the code:

    SQL > select * from v version $;

    BANNER

    --------------------------------------------------------------------------------

    Oracle Database 11 g Release 11.2.0.3.0 - 64 bit Production

    PL/SQL Release 11.2.0.3.0 - Production

    CORE Production 11.2.0.3.0

    AMT for 64-bit Windows: Version 11.2.0.3.0 - Production

    NLSRTL Version 11.2.0.3.0 - Production

    SQL > CREATE INDEX IDX_SRE_E_MAIL_UPPER on fsynrelatie (upper (sre_e_mail)) tablespace idx;

    CREATE the INDEX IDX_SRE_E_MAIL_UPPER on idx tablespace fsynrelatie (upper (sre_e_mail))

    *

    ERROR on line 1:

    ORA-30553: the function is not deterministic

    SQL > create table fsynrelatie2 in select * from fsynrelatie;

    Table created.

    SQL > CREATE INDEX IDX_SRE_E_MAIL_UPPER on fsynrelatie2 (upper (sre_e_mail)) tablespace idx;

    The index is created.

    SQL > drop table fsynrelatie2;

    Deleted table.

    SQL > show parameter query_rewrite_enabled

    VALUE OF TYPE NAME

    ------------------------------------ ----------- ------------------------------

    query_rewrite_enabled string TRUE

    Hi all

    Thank you for the answers. I found the problem:

    On the table, there are 54 index:

    Select index_type, uniqueness, count (*) from user_indexes where table_name = 'FSYNRELATIE '.

    Index_type group, uniqueness

    INDEX_TYPE SINGLE CHARACTER COUNT (*)
    FIELD ARE NOT UNIQUE 1
    BASED ON A NORMAL FUNCTION ARE NOT UNIQUE 4
    NORMAL UNIQUE 3
    NORMAL ARE NOT UNIQUE 46

    3 unique indexes are the primary key and 2 another witch number field contains unique identifiers for rows in other systems. The domain index is an index of Oracle text on a couple of fields. There are 3 indices of function based on a high on a field and 1 on an individual function. This last clue has caused the problem. Apparently, on the creation, this function is deterministic, but when rolling a new version of the software. It became a non-deterministic function. When I delete the index, my original index on upper (sre_e_mail) has been created successfully! Now, I did the deterministic function again and could recreate the function without problem.

    Thanks for your comments!

  • Functions and deterministic performance of gain.  What is the reality behind?

    Hello Pros,

    What is that we really can win using the deterministic function. I've seen some good examples of askthom and discussions. After reading these examples, I feel deterministic functions are rarely used and the benefits are neglected. Is my thoughts right? Requst the pro s to discuss on how used this deterministic function or how better can be used in the right places to take advantage of the performance.

    [url http://asktom.oracle.com/pls/apex/f?p=100:11:0:P11_QUESTION_ID:1547006324238 #12928321943595] Example site asktom

    Here is the link I had called and taken a few examples out of it.

    Thanks in advance

    You can also see the CBO in action (optimize SQL code and do not stuff that is not necessary to determine the final result).

    Think the feature is actually executed when you use a SQL as follows? :-)

    SQL> exec global.counter := 0;

PL/SQL procedure successfully completed.

SQL> select count(*) from (select SpecialFoo(level/level)  as X from dual connect by level <= 10000);

  COUNT(*)
----------
     10000

SQL> exec dbms_output.put_line( 'execution='||global.counter );
execution=0

PL/SQL procedure successfully completed.

SQL>

  • Function Index problem.

    Hello

    I have a problem regarding a function function index.

    example:

    TableName: Test

    Column: A, B, C, D

    I create the index on the table, column, a test using a user-defined function.

    If I do a select on the column, he'll be fine. In other words, I'll get the results you want.

    However, if I insert in the table and validation, and I do a query using the 'A' column in the where clause. I don't have any query hits. Its really weird.

    Have you ever experienced this problem? and is there an index of function according to back and donts w.r.t.?

    Thank you.

    MichaelR

    If you use a deterministic function really, it works:

    create or replace function test_fn (p_number number) return number deterministic
is
  vreturn number := 0;
begin
  if p_number = 1 then vreturn := 55; end if;
  if p_number = 2 then vreturn := 89; end if;
  return vreturn;
end;

    Or, if you reverse the order of your second inserts (insert the folder before the recording of test1 test2) - it works fine.

    The reason why you get no results is when you insert the file test1 with a = 2, Oracle executes the function and gets no data, so it assumes that the result is NULL and puts in the index. You said Oracle function is deterministic, so he starts from the principle that any time test_fn (2) is called, it retrieves a null response.

  • Function index in Oracle

    Hi gurus,

    Just trying to get some info in the function-based index.

    Can we have index created in the user-defined function?

    Lets say we have a table and I need a counter of a column. Could we have indexes on County?

    Select count (name) of employee

    WHERE name = "Hary";

    Thank you

    Tina

    The functions used in the function-based index must be DETERMINISTIC.

    Example you is not deterministic, that is given the input, the output can vary, because there might be 10 Harys today and 5 tomorrow.

    Deterministic functions always return the same value for the same entry.

    See: http://docs.oracle.com/cd/E11882_01/appdev.112/e25519/function.htm#LNPLS1580

  • How to make a generic function?

    Hi all

    I am using oracle 11g.

    My question is how can I do a generic function to escape some special charecters.

    Currently, I use this way.

    Select Replace (replace (replace (FACILITY_ADDRESS,'-','-'), "','------" '),'"','------"') installation;

    above, I give for a column, in the same way, I do for some more columns

    so I need a generic function, and I'll use this function in each columns that depends on the State.

    Thank you

    Dale

    search for deterministic function?

    create or replace function repl (p varchar2) return varchar2 deterministic as

    Start

    return replace (replace (replace (p, '-','-'), "',' \" ') ', ' "' ','------" ');

    end;

    ----

    Ramin Hashimzade

  • function and packages

    Hi friends,

    I have a requirement where in I need decode my source table values while inserting in my target table. I usually do my task by performing functions (don't use case and decode). My first question is

    (1) is using the function to accomplish these tasks is good. I have several of these conversion requirements.
    (2) Clubbing subprogrammes togther in packages is a good habit. But what should be the number of these subprogrammes. I can club togther 100 of this togther functions (a function of the average is 50 lines)? If this is not the case, what should be the thoughts of segregation?
    (3) are the oracle integrated like sqrt, length etc. deterministic functions?

    This code represents a typical requirement of the mine where in I map my name of source country in the target
    ID of country when migrating my data from the source to the target.

    create table source 
(
emp_id number,
empname varchar2(100),
sal number,
country varchar2(100)
);


insert into source values (1,'ALEX',1000,'US');
Insert into source values (2,'RAHUL',2000,'IND');
Insert into source values (3,'KARTIK',3000,'IND');
Insert into source values (4,'SHADOW',5000,'US');
insert into source values(5,'LOUI',1500,'JAP');


Create table source_country_code
(
country varchar2(100),
abbrv  varchar2(100),
area number,
climate varchar2(100)
);

insert into source_country_code values ('UNITED STATES','US',10000,'COLD');
insert into source_country_code values ('INDIA','IND',100000,'HOT');
insert into source_country_code values ('JAPAN','JAP',1000000,'MODERATE');




Create table target_country_code
(
country_id number,
descr  varchar2(100),
density number,
weather varchar2(100)
);

insert into target_country_code values (101,'this is descrition txt 1',1001,'COLD');
insert into target_country_code values (102,'this is descrition txt 2',1001,'HOT');
insert into target_country_code values (103,'this is descrition txt 3',1001,'MODERATE');



create table target
(
emp_id number,
empname varchar2(100),
sal number,
country_id number
);
    I generally functions for this kind of mappings. I have several of these requirements as indicated above and the
    cardinality of data is high.
    create or replace function transform (in_src_country varchar2) return number deterministic
as
l_country_id number;
l_climate varchar2(1000);
begin

select climate into l_climate from source_country_code
   where upper(abbrv)=upper(in_src_country);
   
select country_id into l_country_id
from target_country_code
where upper(weather)=upper(l_climate);

return(l_country_id);
exception 
when no_data_found then
return null;
end;
    last step,

    so, what I usually do is

    insert into target
    Select emp_id, empname, sal, transform (country) in the source;



    As always, thank you

    Rahul

    Published by: Rahul K on 5 June 2013 10:51

    No technique is universally good or bad universally. You must understand your needs, the compromise and what you're trying to optimize for.

    If you don't care anything else you are looking for the absolute fastest performance, reduce what you have to do in PL/SQL is a good idea. Most of the people and most of the systems, however, prefer to have code that is a bit slower if it makes the code easier to maintain and easier to write or minimizes the number of places that the code is duplicated. If you attempt to load a data warehouse of company with billions of new lines every night, you're as almost exclusively worry about raw performance. And, if you design correctly, there is that one way to load any particular item of data, you don't have to worry about code duplication because there will always be an INSERT statement that inserts data in a particular table. If you build an OLTP application, on the other hand, it is very likely that there will be many places where you want to do something like search for a value and you are much less concerned about raw performance you're on maintainability and ensure that you do not duplicate the code. In these cases, well-designed functions and procedures are well worth the return miners (so if you do a query of single line as most OLTP systems are generally easier to treat if you write DSS queries that return millions of processing lines billionr lines.

    Justin

  • Oracle result Cache problem

    Hello

    In our database, we have the following settings for caching the result:

    result_cache_max_result integer 5

    result_cache_max_size great whole 256256 K

    result_cache_mode chain MANUAL

    result_cache_remote_expiration integer 0

    But we use indicators no results hidden in questions, or tables that are enabled for result caching.

    So from my understanding, caching the result should not happen.

    But we met a performance problem, and when I checked the AWR report I found this:

    latchfree.PNG

    And also I found this activity latch:

    rclatch.PNG

    However, just set result_cache_max_size = 0 fixed to all our questions. Wait no more. Performance as expected.

    But how is that possible? I thought with result_cache_mode = manual and not using indicators of result cache or table modes,.

    There should be no result at all caching? Any max_size choose?

    Can someone help me understand what is happening here?

    Thank you and greet.

    Daniel

    tylerv wrote:

    The original poster was not to the point and they actually understand the docs.

    Sorry - I'm not okay. As I went to the docs are very EXPLICIT about how to disable the cache of result. If you turn it off, then it is enabled.

    The fact that they have tried to do is that when result_cache_mode is set to the default value of the MANUAL, because they showed, it is, while according to the docs 12 c only the results of queries that use the RESULT_CACHE indicator must be stored in the cache of result

    Maybe that's where you and OP have misunderstanding. on the RESULT_CACHE_MODE parameter and the parameter values. This seems to be a common misunderstanding.perhaps, because people are not read ALL the relevant articles of the RFSO and only looking at the section for this parameter.

    There is NOTHING in the doc of 12 c for this parameter that shows ANY correlation to determine whether the cache is enabled or not.

    Refer to the section "Setting the Mode of the result Cache"

    https://docs.Oracle.com/database/121/TGDBA/tune_result_cache.htm#CDEJCGJD

    As shown in table 15-3 there are ONLY two settings: MANUAL and FORCE. No adjustment said ANYTHING on toggle or if the cache is ENABLED or DISABLED.

    ... and they were not aware of all the queries that they had used this trick on.  When you're ready to values by default and don't use don't not result_cache indicator (as much), it's odd to find the cache of your result are so full.

    OK - the USER does not use the indicator result-cache to cache the results of the queries USERS. But if the cache is enabled (size not equal to zero) that according to the quote from the doc above has NO effect on the use of Oracle to cache for queries or non-deterministic function calls.

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    .

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    An index on the child table can reference only the columns of the child table.  You can't have an index on the child table that is based on information from the parent table.

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    <code>
create or replace
PACKAGE  passwd_enc_dec 
as
                    
  FUNCTION main_key(p_key              in varchar2) RETURN RAW DETERMINISTIC;
                     encryption_type    pls_integer;
                     ENCRYPTION_KEY     RAW (32);
  FUNCTION encrypt (p_plainText VARCHAR2) RETURN RAW DETERMINISTIC;
  FUNCTION decrypt (p_encryptedText RAW) RETURN VARCHAR2 DETERMINISTIC;
END;
/
create or replace
package body  test
as
                    
  encryption_key     raw (32);
FUNCTION MAIN_KEY(P_KEY IN VARCHAR2) RETURN RAW DETERMINISTIC IS 
 encryption_key  raw(2000);
 encryption_type    pls_integer;
begin
  encryption_type := dbms_crypto.encrypt_des
                   + dbms_crypto.chain_cbc
                   + dbms_crypto.pad_pkcs5;
  ENCRYPTION_KEY      := UTL_RAW.CAST_TO_RAW(P_KEY);
  return ENCRYPTION_KEY;
EXCEPTION
  WHEN OTHERS THEN NULL;
  END MAIN_KEY;
  
FUNCTION ENCRYPT (P_PLAINTEXT VARCHAR2) RETURN RAW DETERMINISTIC IS
  encrypted_raw      raw (2000);
  crypto_key raw(2000);
  
begin
  crypto_key := main_key(p_plaintext);
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                     TYP => ENCRYPTION_TYPE,
                     KEY =>crypto_key);
  RETURN ENCRYPTED_RAW;
  
EXCEPTION
  when others then return encrypted_raw;
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function decrypt (p_encryptedtext raw) return varchar2 deterministic is
  decrypted_raw      raw (2000);
  dummy varchar2(1000);
  decrypto_key raw(2000);
begin
  decrypto_key := main_key(p_encryptedtext);
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                     src => p_encryptedtext,
                     typ => encryption_type,
                     key => decrypto_key );
  return (utl_raw.cast_to_varchar2 (decrypted_raw));
exception
  
  when others then 
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  return (utl_raw.cast_to_varchar2 (decrypted_raw));
end decrypt;
end;

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    Start

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    end;

    end;

    /

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    Hello

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    FUNCTION decrypt (p_encryptedText RAW) RETURN VARCHAR2 DETERMINISTIC;
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    Kind regards
    007

    >
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    >
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