Order columns (which make up the primary key constraint) matter in where clause of DML query for use of indexing mechanism to operate.

Version of DB: database Oracle 11 g Enterprise Edition Release 11.2.0.3.0 - 64 bit Production


I have a table my_table as below:
create table my_table
(
my_code varchar2 (6).
my_id varchar2 (24).
forced pk_1 primary key (my_code, my_id)
);


Primary_key here's a composite key that contains columns 1 (my_code) and 2 (my_id).
Is there that a difference in the way below queries is executed in terms of performance (use of indexing in the extraction).

(a) select * from my_table where my_code = '123' and my_id = "456";
(b) select * from my_table where my_id = '456' and my_code = '123';


The understanding I have the order of the column in the where clause should be identical to the sequence in
What primary key draws for indexing to be used by oracle in oracle other DML queries ignores indexing
However when I used explain plain both show the same query cost with single scan with index rowid.
so I don't know if I'm wrong in the concept that I have. Kindly help.

Thanks in advance,
Gerard

Your question is answered in the Performance Tuning Guide

Using indexes and clusters

14.1.4 choosing composite indexes

A composite index contains several key columns. Composite indexes can provide additional benefits compared to the index to single column:

  • Improved selectivity

    Sometimes the two or more columns or expressions, each with a low selectivity can be combined to form a composite with a high selectivity.

  • Reduced IO

    If all columns selected by a query are a composite index, then Oracle may return these values in the index without access to the table.

A SQL statement can use a path on a composite index if the statement contains constructions that use a main part of the index.

Note:

This is no longer the case with the skip index scans. See "Index Skip Scans".

A main part of an index is a set of one or more columns that have been specified first and consecutively in the list of columns in the CREATE INDEX statement that created the index.

Tags: Database

Similar Questions

  • by specifying the index tablespace in to disable the primary key constraint

    Hello
    during the ETL I want to disable constraints PK/UK to speed up the load;
    on activation of the constraint, the corresponding indices are created in a different tablespace while they were initially on the creation of the table itself
    I tried to disable PK / UK with the option 'keep the index', the index value corresponding to the status of "unusable" and use ' alter session set skip_unusable_indexes = true', but then I can't insert rows with the error.
    Error: ORA-01502: index 'xxx' or partition of such index is in unusable state
    can anyone tell if there is a way to allow the PK/UK constraint and specify the storage space for the corresponding indices, or keep the index and inserts works?
    I'd like to avoid to drop constraints / indexes and re-create them both from scratch after the load
    Thank you for the advice
    Thank you
    Rgds

    >
    can anyone tell if there is a way to allow the PK/UK constraint and specify the storage space for the corresponding indices, or keep the index and inserts works?
    I'd like to avoid to drop constraints / indexes and re-create them both from scratch after the load
    >
    Have you tried specifying the table space in the USING clause when you activate the constraint?

    ALTER TABLE emp ENABLE PRIMARY KEY USING INDEX TABLESPACE myTS;
    

    See DBA guide
    http://docs.Oracle.com/CD/B28359_01/server.111/b28310/indexes003.htm
    >
    Creating an Index associated with a constraint

    Oracle database applies a UNIQUE key or a constraint integrity PRIMARY KEY on a table by creating a unique index on the unique key or primary key. This index is created automatically by the database when the constraint is enabled. No action is required by you when you run the CREATE TABLE or ALTER TABLE statement to create the index, but you can optionally specify an ESCALATION using clause to exercise control over his creation. This includes them when a constraint is defined and enabled, and when a constraint defined but disabled is selected.
    >
    Note the last sentence two sentences:
    >
    You can optionally specify an ESCALATION using clause to exercise control over his creation. This includes them when a constraint is defined and enabled, and when a constraint defined but disabled is selected.
    >
    You realize, I hope, that the only way can Oracle KNOWS that the index contains valid values is to rebuild?

  • blocking because of the primary key constraint

    Hi all

    Recently, we migrated to 9.2.0.4 to 10.2.0.4. In the new version of oracle there was a strange behavior, we have 200 + oracle database user and there was too much blocking on a particular one table, we looked and looked for the cause but found nothing exact reason, then on the internet somewhere, we found that if a primary key is disabled and no there is also foreign then blocking is caused for example

    CREATE TABLE TEST_MST
    (
    MST_COL1 NUMBER,
    MST_COL2 NUMBER,
    MST_COL3 NUMBER
    )

    CREATE TABLE TEST_DTL
    (
    MST_COL1 NUMBER,
    MST_COL2 NUMBER,
    MST_COL3 NUMBER,
    DTL_COL1 NUMBER,
    DTL_COL2 NUMBER,
    DTL_COL3 NUMBER
    )

    ALTER TABLE TEST_MST ADD)
    CONSTRAINT PK_TM
    KEY ELEMENTARY SCHOOL
    (MST_COL1, MST_COL2, MST_COL3)) ;

    ALTER TABLE TEST_DTL ADD)
    CONSTRAINT PK_TD
    KEY ELEMENTARY SCHOOL
    (MST_COL1, MST_COL2, MST_COL3, DTL_COL1, DTL_COL2)) ;

    ALTER TABLE TEST_DTL ADD)
    CONSTRAINT FK_TM_TD
    FOREIGN KEY (MST_COL1, MST_COL2, MST_COL3)
    REFERENCES TEST_MST (MST_COL1, MST_COL2, MST_COL3));

    ALTER TABLE TEST_DTL
    DISABLE THE CONSTRAINT PK_TD;


    so, I just want to be sure that's the exact reason only blocking sessions and if yes, then why not so happning.

    Thanks and Rgds,
    Piyush
  • dynamically find the primary key of a table

    Hello

    How can I see (dynamically) participating in a primary key table columns?

    Let's imagine that we have a procedure receives the name of the table as a parameter:
    PROCEDURE delete_record (table_name IN VARCHAR2)
    The procedure is to delete a record in the table 'table_name '.
    -- g_record is a global variable containing the values of the record that should be deleted.
    l_sql_statement := 'DELETE FROM ' || table_name || ' WHERE ' || primarykey_col_1 || '=' || g_record.col_1;
    
    EXECUTE IMMEDIATE l_sql_statement;
    So, how do I see the columns that make up the primary key, perhaps, somehow the using the description of the table?

    Thank you!

    You can use the ALL_CONSTRAINTS in combination with views ALL_CONS_COLUMNS to retrieve this information (there are also views DBA_ and USER_ as well). Here is a sample of SQL that you could use:

    SELECT  COLUMN_NAME
    FROM    ALL_CONSTRAINTS         AC
    JOIN    ALL_CONS_COLUMNS        ACC     ON ACC.TABLE_NAME       = AC.TABLE_NAME
                                           AND ACC.CONSTRAINT_NAME  = ACC.CONSTRAINT_NAME
    WHERE   CONSTRAINT_TYPE = 'P'
    AND     ACC.TABLE_NAME  = table_name
    

    I wonder however this method because it seems unorthodox. Could you provide a reason for this kind of implementation?

  • How to refer to the primary key column of newly inserted rows of tabular form

    Hello

    I use APEX 4.2.0.00.27 with Oracle DB 11.2.0.3.0.

    I work with a tabular presentation wizard-created for insert and update a table using the integrated SRM process (sequence 10).  I'm trying to use a process of anonymous block of PL/SQL (sequence 30) to make another manipulation of table after the records were inserted or updated.  The manual process is associated with my tabular form and I use the variables of name of column binding in my program block.

    My (rsn_test) table has 3 columns: test_id (number), test_nbr (number), test_id2 (number).  Test_id column is identified as the primary key and the type of the source already exists a sequence rsn_test_seq.  Column test_id2 gets its default value 0 to a hidden page element.

    I would use my manual process for updating the value of the test_id2 column.  If it's 0 then I want to put the value of the column test_id.  If it is any other value, then it must remain at this value.  My logic works very well for an existing line, but I'm running into a problem with the newly added lines.  The new lines get inserted, but the test_id2 column remains the default value 0.  I can tell the debugger that the SRM process is triggered first and inserts the line, then my manual dealing with fires.  The problem seems to be that the connection variable: TEST_ID for the primary key column remains NULL after insertion.  I don't know how to get the value of the column test_id of my newly created line to use in my PL/SQL block to my update.

    Process of PL/SQL:

    DECLARE
    BEGIN
       :P7_SHOW := NULL;
       :P7_SHOW := NVL(:TEST_ID2,555) || ' and ' || NVL(:TEST_ID,787) || ' and ' || NVL(:TEST_NBR,9999);
       IF :TEST_ID2 = 0 AND :TEST_ID IS NOT NULL THEN
          UPDATE rsn_test
             SET test_id2 = :TEST_ID
           WHERE test_id = :TEST_ID;
       ELSE
          :TEST_ID2 := :TEST_ID2;
       END IF;
    END;
    
    

    Excerpt from the debugger:

    0.01625 0.00010 Processes - point: ON_SUBMIT_BEFORE_COMPUTATION
    0.01635 0.00008 Branch point: Before Computation
    0.01643 0.00003 Process point: AFTER_SUBMIT
    0.01646 0.00022 Tabs: Perform Branching for Tab Requests
    0.01668 0.00008 Branch point: Before Validation
    0.01676 0.00024 Validations:
    0.01700 0.00135 Perform basic and predefined validations:
    0.01835 0.00020 Perform custom validations:
    0.01855 0.00049 ...Validation "TEST_NBR must be numeric" - Type: ITEM_IS_NUMERIC
    0.01904 0.00007 ......Skip for row 1 because row hasn't changed
    0.01911 0.00016 ......Skip for row 2 because row hasn't changed
    0.01927 0.00012 ...Validation "TEST_ID2 must be numeric" - Type: ITEM_IS_NUMERIC
    0.01939 0.00007 ......Skip for row 1 because row hasn't changed
    0.01945 0.00018 ......Skip for row 2 because row hasn't changed
    0.01964 0.00005 Branch point: Before Processing
    0.01968 0.00004 Processes - point: AFTER_SUBMIT
    0.01972 0.00588 ...Process "ApplyMRU" - Type: MULTI_ROW_UPDATE
    0.02560 0.00154 ...Execute Statement: declare function x return varchar2 is begin begin for c1 in ( select "RSN_TEST_SEQ".nextval pk from sys.dual ) loop return c1.pk; end loop; end; return null; end; begin wwv_flow.g_value := x; end;
    0.02714 0.00140 ......Row 3: insert into "APPPCSRSN"."RSN_TEST" ( "TEST_ID", "TEST_NBR", "TEST_ID2") values ( :b1, :b2, :b3)
    0.02854 0.00011 ...Process "ApplyMRD" - Type: MULTI_ROW_DELETE
    0.02865 0.00004 ......Skip because condition or authorization evaluates to FALSE
    0.02869 0.00015 ...Process "Process Submit" - Type: PLSQL
    0.02884 0.00007 ......Skip for row 1 because row hasn't changed
    0.02891 0.00012 ......Skip for row 2 because row hasn't changed
    0.02903 0.00012 ......Process row 3
    0.02915 0.00429 ...Execute Statement: begin DECLARE BEGIN :P7_SHOW := NULL; :P7_SHOW := NVL(:TEST_ID2,555) || ' and ' || NVL(:TEST_ID,787) || ' and ' || NVL(:TEST_NBR,9999); IF :TEST_ID2 = 0 AND :TEST_ID IS NOT NULL THEN UPDATE rsn_test SET test_id2 = :TEST_NBR WHERE test_id = :TEST_ID; ELSE :TEST_ID2 := :TEST_ID2; END IF; END; end;
    0.03344 0.00013 ...Session State: Saved Item "P7_SHOW" New Value="0 and 787 and 1300"
    0.03356 0.00004 Branch point: After Processing
    0.03360 0.00048 ...Evaluating Branch: "AFTER_PROCESSING" Type: REDIRECT_URL Button: (No Button Pressed) Condition: (Unconditional)
    0.03407 0.00013 Redirecting to f?p=290:7:8717971109610:::::&success_msg=0%20row(s)%20updated%2C%201%20row(s)%20inserted.Success%2FEBD244168556408CBA714E3974918C09%2F
    0.03420 0.00012 Stop APEX Engine detected
    0.03432 0.00007 Stop APEX Engine detected
    0.03439 - Final commit
    
    

    Any suggestions?

    I have run tests on

    https://apex.Oracle.com/pls/apex/f?p=83488:1 demo/demo

    to see your problem.

    I have 2 solution for your problem.
    I add trial NOT tabular just usual block of PL/SQL

    BEGIN
    I'm IN (SELECT TEST_ID FROM RSN_TEST WHERE TEST_ID2 = 0)
    LOOP
          UPDATE RSN_TEST
             SET test_id2 = TEST_ID
           WHERE test_id = i.TEST_ID;
      END LOOP;
    END;

    and works very well, you can see in the sample.

    The other solution is to show new generated TEST_ID

    Adding a sequence as a default value for a column in a table field

    And to execute your procedure.

    I get how is with the good luck of time.

    By

  • creating a unique index of instaed of using the primary key index

    Hello

    I heard in a debate sometimes it is better to create a unique index on a column and use it instead of using the primary key index in oracle. I did not understand what that the reason propely.

    Can someone please help me in this topic if it is valid.

    Thanks in advance

    On the surface, which does not seem reasonable... Volume of the DML is irrelevent to determine which column is the primary key for a table.

    My wild speculation a bit at a reasonable time could someone do...

    If you use synthetic primary keys (i.e. the keys generated by sequence) and that your tables are subject to large volumes of inserts such as there is a danger that the block "to the right" will be the source of contention block and worry not about analysis of beach on the column, you can create a reverse on this column (unique or non-unique) key index before creating the primary key constraint and to indicate Oracle to use this existing index to respect the primary key constraint.

    Obviously, however, this involves a lot of assumptions to arrive at a reasonable point. There may well be another set of assumptions that could also lead to a valid argument. Or it could be a myth that someone has heard and just repeats.

    Justin

  • Create the primary key on the target

    Y at - it no IKM which would create the primary key on target after having read the instructions for the source?

    Thank you
    Dinesh.

    Hi Dinesh,

    You can customize a KM to create a primary key on the target
    The target table will be created with the mention of the primary key constraint in the data target store.

    Steps: -.

    Customiuse creating target step of the table and I create $ step table.

    for example: -.

    original train target table KM walk (IKM Oracle Simple incremental update): -.

    create table< %="snpRef.getTable" ("l",="" "a",="" "targ_name")="" %="">
    (
         <%=snpRef.getTargetColList("", "[COL_NAME]\t[DEST_CRE_DT] NULL", ",\n\t", "")%>
    )

    custom STAGE: -.

    create table< %="snpRef.getTable" ("l",="" "a",="" "targ_name")="" %="">
    (
         <%=snpRef.getTargetColList("", "[COL_NAME]\t[DEST_CRE_DT] NULL", ",\n\t", "")%>

    CONSTRAINT constraint_name PRIMARY KEY (< %="snpRef.getColList" ("",="" "[column]",="" ",",="" "",="" "pk")="" %="">)
    )

    Note:- The code above described here is just a sample of reference. I did not test the syntax.

    Kind regards
    Its

  • Automatically fill the primary key

    We have Oracle database 10g. I've added a primary key column to my deo_language_resources_t of table with the following logic:

    -- 1. create sequences
    create sequences eod_lr_seq
    Start increment by 10 by 5
    MinValue 10 nomaxvalue
    NoCache;

    -- 2. Create the primary key column
    ALTER table deo_language_resources_t
    ADD NUMBER RESOURCE_ID;

    -- 3. Fill the pk
    Update deo_language_resources_t
    Set id_ressource = eod_lr_seq.nextval
    where id_ressource is null;

    -- 3. Create the primary key constraint
    ALTER table deo_language_resources_t
    Add constraint resource_id_pk key (resource_id) primary;

    insert into deo_language_resources_t
    (first_name, last_name, id_ressource)
    values ('John', 'Doe', eod_lr_seq.nextval);

    The last INSERT statement successfully a line inserted into the table and populated by id_ressource with the next number in the sequence eod_lr_seq. Ok.

    Is it possible to set a constraint on deo_language_resource_t so that when I INSERT a line the id_ressource is automatically set to eod_lr_seq.nextval? It is possible to define a trigger and resembling the logic of the trigger? The insert statement would be like:

    INSERT INTO deo_language_resources_t (first_name, last_name) VALUES ('John', 'Doe');
    create trigger deo_language_resources_trigger
    before insert on deo_language_resources_t
    for each row
    begin
    select eod_lr_seq.nextval into :resource_id from dual;
    end;
    
  • Too many objects correspond to the primary key oracle.jbo.Key

    I get this error: Too many objects match the primary key oracle.jbo.Key when I tried to look for in a display object where the primary key is consists of more than one filed.

    Use case:

    In Jdeveloper 11.1.2.3 I Entity object called someTable this table has three fields A,B and C where the primary key is consist class towing A and B .

    I created different towing View object of someTable object enity that are someTableVO1 and someTableVO2 . Rated A in the view object somtableVO1 is a List Of Value(LOV) and the data are coming form filed A in the someTableVO2 .

    In application I have a search page that contains a drop-down list of registered A in somTableVO1 . Based on certain conditions, the drop-down list of the values in the list is not static. The value of the drop-down list is editable based on a select query run on someTableVO1 and it is based on the class thried C is NOT part of the primary key .

    The page displays the drop down menu with the correct values. But I have a ValeChangeListener method that will be activated whenever the user selects a value form the drop-down list.

    The problem is:

    The error Too many objects match the primary key is occur whenever I am executing this method.

    Support:

    I think the problem is with multiple fields for the primary key. of curse, there is an overlap in a part of the primary key (IE that paid A or B ) but the combination of A and B are always unique.

    Notes:

    1. I check the query by executing SQL Developer and it shows not all duplicate values.

    2 I don't attach code, because I think that the problem is not on (how to) this is (what to do).

    I hope that the idea is clear

    Problem solved.

    My goal was to show a summer that A form someTableVO1 as a list of value and I was trying to achieve by creating the list of value the same form Entity object . I understand that it was the wrong approach (correct me if I'm wrong). to achieve this in ADF technology, I have to do the following:

    1. Simply to drag and drop the view object from the Data Controls page.
    2. List of options appears asking how you want to display the view object (shape, chart, table, only one selection,...).

    3. Select Single Selection ->ADF one Selection

    4. Select the attributes that you want to show the user a list of values.

    Thanks for your comments.

  • Direct path SQLLDR allows duplicates in the primary key

    I would use sqlldr path direct to charge millions of records in the table but direct way allows duplicates on the primary key constraints.

    inserts of duplicates
    sqlldr control deploy_ctl/deploy_ctl@dba01mdm = direct ctl_test.ctl = true
    primary key is enabled

    I do not understand the behavior that's why the primary key is always enabled--(logiquement il doit avoir désactivé que doublons insérés)

    Inserts no duplicates
    sqlldr control = ctl_test.ctl deploy_ctl/deploy_ctl@dba01mdm
    primary key is enabled

    Please can I know if there is any work around to use direct path with constraints of primary school in place.

    The only solution is to not use direct load, if your dataset contains records in duplicate, of the documentation:

    /*
    A record that violates a UNIQUE constraint is not rejected (the file is not available in the memory when the constraint violation is detected).
    */

  • modify a primary key constraint

    Hello

    I start with oracle, and I have two doubts which cannot handle after a search on the internet.

    1. it is possible to do an ALTER TABLE for a DEFAULT CONSTRAINT?. Maybe you think that the question should be in a different way like this: oracle database takes the default condition as a constraint?. As far as I know, not done that.

    2. it is possible, with an ALTER TABLE to CHANGE a CONSTRAINT of a PRIMARY KEY, to add another field more?

    I searched the internet, but I have not found a clear answer. I use oracle 10g express edition.


    Thank you very much.

    P.D.:sorry for my English, it is not very good.

    #2-you can not 'add a column to the primary key of a table constraint' with a single ALTER, but you can delete and re-create the constraint primary key (including the additional column).

    13:25:26> create table t1 (a number primary key, b number, c number );
    
    Table created.
    
    Elapsed: 00:00:00.09
    13:25:46> alter table t1 drop primary key;
    
    Table altered.
    
    Elapsed: 00:00:00.06
    13:25:47> alter table t1 add primary key (a,b);
    
    Table altered.
    
    Elapsed: 00:00:00.09
    

    But you will not be able to drop the primary key of a table index.

    13:25:47> create table t2 (a number primary key, b number, c number ) organization index;
    
    Table created.
    
    Elapsed: 00:00:00.03
    13:25:59> alter table t2 drop primary key;
    alter table t2 drop primary key
    *
    ERROR at line 1:
    ORA-25188: cannot drop/disable/defer the primary key constraint for
    index-organized tables or sorted hash cluster
    
    Elapsed: 00:00:00.00
    13:25:59> 
    

    #1-I'm not sure I understand your question, but you can change a table column to have a default value. This isn't a "constraint", but a default value. It has an effect when you perform an insert which does not include this column.

    13:31:23> alter table t1 modify (c default 3.14);
    
    Table altered.
    
    Elapsed: 00:00:00.04
    13:31:24> insert into t1 (a,b,c) values (1,2,3);
    
    1 row created.
    
    Elapsed: 00:00:00.01
    13:31:24> insert into t1 (a,b,c) values (4,5,NULL);
    
    1 row created.
    
    Elapsed: 00:00:00.00
    13:31:24> insert into t1 (a,b) values(6,7);
    
    1 row created.
    
    Elapsed: 00:00:00.01
    13:31:24> select * from t1;
    
             A          B          C
    ---------- ---------- ----------
             1          2          3
             4          5
             6          7       3.14
    
    3 rows selected.
    
    Elapsed: 00:00:00.18
    
  • primary key constraint...

    Hi all

    I have a table 'employees' on 'hr' scheme, now, I created a user 'rahul' on the same database and pulling a request by logging in with the user "rahul" which is:

    create table rahul.employees
    as (select * from hr.employees); -ps: I have the privilege to read data from hr.employees

    Now, the above query works fine, the only issue is that employe_id is the primary key for the table hr.employees and when I check the table of rahul.employees, the pruimary key constraint is missing, however the structure of the table and the data is there according to my expectations.

    I so want to know how to create a table with data using the definition of schema_name.table_name as well as the primary key constraint.

    Concerning
    Rahul karou

    Mac_Freak_Rahul wrote:
    Thanks for the reply, but this query returns me nothing, is it a question of privilege?

    Concerning
    Rahul

    Are you an error? Otherwise, the result will be CLOB, just copy from your clint tool and paste it into a Notepad...

    between it's table

    CREATE TABLE "HR"."EMPLOYEES1"
       (     "EMPLOYEE_ID" NUMBER(6,0),
         "FIRST_NAME" VARCHAR2(20),
         "LAST_NAME" VARCHAR2(25) CONSTRAINT "EMP_LAST_NAME_NN" NOT NULL ENABLE,
         "EMAIL" VARCHAR2(25) CONSTRAINT "EMP_EMAIL_NN" NOT NULL ENABLE,
         "PHONE_NUMBER" VARCHAR2(20),
         "HIRE_DATE" DATE CONSTRAINT "EMP_HIRE_DATE_NN" NOT NULL ENABLE,
         "JOB_ID" VARCHAR2(10) CONSTRAINT "EMP_JOB_NN" NOT NULL ENABLE,
         "SALARY" NUMBER(8,2),
         "COMMISSION_PCT" NUMBER(2,2),
         "MANAGER_ID" NUMBER(6,0),
         "DEPARTMENT_ID" NUMBER(4,0),
          CONSTRAINT "EMP_SALARY_MIN" CHECK (salary > 0) ENABLE,
          CONSTRAINT "EMP_EMAIL_UK" UNIQUE ("EMAIL")
      USING INDEX  ENABLE,
          CONSTRAINT "EMP_EMP_ID_PK" PRIMARY KEY ("EMPLOYEE_ID")
      USING INDEX ENABLE,
          CONSTRAINT "EMP_MANAGER_FK" FOREIGN KEY ("MANAGER_ID")
           REFERENCES "HR"."EMPLOYEES" ("EMPLOYEE_ID") ENABLE,
          CONSTRAINT "EMP_JOB_FK" FOREIGN KEY ("JOB_ID")
           REFERENCES "HR"."JOBS" ("JOB_ID") ENABLE,
          CONSTRAINT "EMP_DEPT_FK" FOREIGN KEY ("DEPARTMENT_ID")
           REFERENCES "HR"."DEPARTMENTS" ("DEPARTMENT_ID") ENABLE
       ) 
    
  • Not Null on the column of a primary key constraint

    I came across a table defined in the same way to...

    create table t (t_id int constraint nn_t_id not null constraint pk_t primary, data key number);

    Of course, the primary key is the is not null, then is there a reason to add the redundant constraint not null?

    There are two parts to your question, I think:

    (1) why add a NOT NULL if a primary key is also reported.
    (2) why is null is NOT a name defined by the user (in this case nn_t_id).

    1 > I think you are right: there is no difference in behavior in the way that Oracle is going to reject the creation of NULL in this column (whether through the direct insert or update with a NULL value). I personally always declares the NOT NULL for columns, I know to never have null, regardless of whether the column is (member of) a PK.

    It's pretty funny, btw, the SQL standard as chosen able to be the NULL default value. I think that we all type much less, if the SQL standard chose NOT NULL default value. But that's another story.

    2 > I don't see given nullability defined by the user of the explicit names now and then, because of some "coding guideline' which dictates that constraint names must never be generated System. This guideline is often presented as a result of the exception handling of "client-side", where the constraint name is filtered SQLERRM and then more personalized to be displayed to the end user. However for NOT NULL constraint violations, I think (does not fully to check) that you are always thrown an ORA-01400 is an ORA-01407. Who nowadays both will tell you exactly (in SQLERRM) which column of this table is currently in violation of a NOT NULL constraint.

    Toon

  • How to find the primary key columns in the tables in MS Access using SQL queries

    How to find the primary key columns in the tables in MS Access using SQL queries

    Hello

    This is the forum for Windows Vista programs related issues.

    For better assistance, please try instead the Forums in SQL Server .

    Thank you! Vincenzo Di Russo - Microsoft MVP Windows Internet Explorer, Windows Desktop Experience & security - since 2003. ~ ~ ~ My MVP profile: https://mvp.support.microsoft.com/profile/Vincenzo

  • Make required error appears only the primary key generated in prior Database Table insert trigger

    Dear all,

    I am a beginner in the ADF and am under Jdeveloper Studio Edition Version 12.2.1.0.0.


    I'm trying to insert a record, I created the trigger for insertion prior to get the primary key and set some other default values.


    On the page, I did read-only primary key column and false required.


    When I try to save - commit (Programmatic), I get errors for the required value. How can I stop this errors.


    Secondly, I also tried changing the agent to disabled on the attribute View object that raised the error below:


    < oracle.dfw.impl.incident.DiagnosticsDataExtractorImpl > < DiagnosticsDataExtractorImpl > < createADRIncident > < incident created 148 to key problem "DFW-99998 [oracle.jbo.PersistenceException] [oracle.jbo.server.RowReference.verifyPrimaryKeys] [Proposals]" >


    Hoping for help.


    Thanks and greetings


    Arif Khadas

    If the primary key values from DB sequence, you can follow this approach:

    Using the sequence of database in ADF - Souza Waslley Blog

    Oracle Fusion Middleware Technologies: ADF 11 G: generate the primary key sequence number

    Otherwise, instead of DB trigger, create the DB function that retrieves the value of the PK and call stored function in the overloaded method create() entity:

Maybe you are looking for

  • Stakeholders with disabilities

    My speakers do not work on board. Helmets work, but the speakers do not present as an option in the sounds configuration panel window.  I think that I have can I have somehow deleted in the Panel thought I was turning off the coast, but now can't fin

  • Cannot download Office updates

    I have problems to download the following updates. How can I download them? Update of security for Microsoft Office Excel 2007 (KB978382) Update of security for Microsoft Office System 2007 (KB976321) Update of security for Microsoft Office System 20

  • Logon administrator password problems

    I have 3 accounts of different profile on my computer.  I can't connect to one of the accounts which is be the administrator.  I get an error saying password failed.  I have not set up a password on any of the accounts, but all of a sudden it says I

  • Windows 8.1 annihilated all win, Pro 7. CANCEL the need help!

    Reference Dell Inspiration 3847 First, I created a new partition and thought that when I pick up the Windows 8.1 since the disc that came with the new computer, it would be a side-by-side, double installation along the side of the factory, preinstall

  • Loading data from SQL to Essbase table

    HelloI'm loading data from SQL to Essbase table by using a rules file. Number of rows in the source table is 7 million. I use the SUNOPSIS MEMORY ENGINE as area transit, LKM SQL for SQL and SQL IKM for Hyperion Essbase (DATA).Question:1 can I not use