a unique index or unique constraint on the issue of view Matt

Similar Questions

• composite unique constraint on the values of parent and child?

  Is it possible to have a composite unique constraint that contains the values of the child elements? The example below has the "child" elements are offline, but it's preferred, but optional, I know that you can have a unique constraint in the set of tables without using a reference table that contains the constraint and the two columns. How xdb manages this requirement?
  
  permit:

  <parent ID="1">
     <child><name>test1</name></child>
     <child><name>test2</name></child>
  </parent>
  <parent ID="2">
     <child><name>test1</name></child>
     <child><name>test2</name></child>
  </parent>

  not allowed:

  <parent ID="1">
     <child><name>test1</name></child>
     <child><name>test1</name></child>
  </parent>

  <xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema" 
             xmlns:xdb="http://xmlns.oracle.com/xdb"
             xdb:storeVarrayAsTable="true"
             elementFormDefault="qualified">
      
      <xs:element name="parent" type="Parent_T"
          xdb:columnProps="CONSTRAINT parent_pkey PRIMARY KEY (XMLDATA.ID)"
          xdb:defaultTable="PARENT"/>
  
      <xs:complexType name="Parent_T" xdb:SQLType="PARENT_T" xdb:maintainDOM="false">
          <xs:sequence>
              <xs:element name="child" type="Child_T" minOccurs="1" maxOccurs="unbounded" xdb:SQLName="CHILD"
                        xdb:SQLInline="false" xdb:defaultTable="CHILD" "/>
          </xs:sequence>
          <xs:attribute name="ID" xdb:SQLName="ID" use="required" />
      </xs:complexType>
      
      <xs:complexType name="Child_T" xdb:SQLType="CHILD_T">
         <xs:sequence>
           <xs:element name="name" type="xs:string" xdb:SQLName="NAME"/>
         </xs:sequence>
       </xs:complexType>     
  </xs:schema>

  xdb:columnProps = "CONSTRAINT parent_pkey PRIMARY KEY (XMLDATA.ID), * UNIQUE (XMLDATA.» "Child.Name) *" triggers the non-existent attribute
  
  
  A possible solution would be to copy the value of the primary key parent of the child element, then I could create a composite unique constraint using only the values of the child. However, I have this same requirement elsewhere in my lowest nested schema, and it can become messy / bad design with cascading of all primary keys on the schema. For example, I have a recursive element in which two attributes must be unique only within the parent company:

  <parent id="1">
     <child a="1" b="1">
        <child a="1" b="2">
           <child a="1" b="1" /> *not allowed
        </child>
     </child>
     <child a="1" b="2" /> *not allowed
  </parent>

  Possible solution:

  <child a="1" b="2" parent_id="1" />
  <xs:complexType name="Child_T>
     <xs:sequence>
        <xs:element name="child" xsd:SQLInline="false" xsd:columnProps="UNIQUE(XMLDATA.a,XMLDATA.b,XMLDATA.parent_id)" minOccurs="0" maxOccurs="unbounded" type="Child_T">
     </xs:sequence>
     </xs:element
  </xs:complexType>

  Is there a better design?
  
  

  Oracle Database 10g Enterprise Edition Release 10.2.0.4.0 - 64bi 
  PL/SQL Release 10.2.0.4.0 - Production                           
  CORE     10.2.0.4.0     Production                                       
  TNS for Linux: Version 10.2.0.4.0 - Production                   
  NLSRTL Version 10.2.0.4.0 - Production 

  You can do something like this:

  SQL> DECLARE
    2
    3    xsd_doc xmltype := xmltype('
    4  
    5    
    6      
    7        
    8          
    9        
   10      
   11    
   12    
   13      
   14        
   15          
   16        
   17      
   18    
   19    
   20      
   21        
   22          
   23        
   24        
   25      
   26    
   27    
   28      
   29        
   30          
   31        
   32      
   33    
   34  ');
   35
   36  BEGIN
   37
   38    dbms_xmlschema.registerSchema(
   39      schemaURL => 'test_parent.xsd',
   40      schemaDoc => xsd_doc,
   41      local => true,
   42      genTypes => true,
   43      genbean => false,
   44      genTables => false,
   45      enableHierarchy => dbms_xmlschema.ENABLE_HIERARCHY_NONE
   46    );
   47
   48  END;
   49  /
  
  PL/SQL procedure successfully completed
  
  SQL> CREATE TABLE my_xml_table OF XMLTYPE
    2  XMLTYPE STORE AS OBJECT RELATIONAL
    3  XMLSCHEMA "test_parent.xsd"
    4  ELEMENT "root"
    5  VARRAY xmldata."parent" STORE AS TABLE my_parent_tab
    6  (
    7    VARRAY "child" STORE AS TABLE my_child_tab
    8  )
    9  ;
  
  Table created
  
  SQL> ALTER TABLE my_parent_tab ADD CONSTRAINT parent_uk UNIQUE (nested_table_id, "ID");
  
  Table altered
  
  SQL> ALTER TABLE my_child_tab ADD CONSTRAINT child_uk UNIQUE (nested_table_id, "name");
  
  Table altered
   
  

  Then:

  SQL> insert into my_xml_table values (
    2  xmltype('
    3     test1
    4     test2
    5  
    6  
    7     test1
    8     test2
    9  ')
   10  );
  insert into my_xml_table values (
  *
  ERREUR à la ligne 1 :
  ORA-00001: violation de contrainte unique (DEV.PARENT_UK)
  
  SQL> insert into my_xml_table values (
    2  xmltype('
    3     test1
    4     test1
    5  
    6  
    7     test1
    8     test2
    9  ')
   10  );
  insert into my_xml_table values (
  *
  ERREUR à la ligne 1 :
  ORA-00001: violation de contrainte unique (DEV.CHILD_UK)
  
  SQL> insert into my_xml_table values (
    2  xmltype('
    3     test1
    4     test2
    5  
    6  
    7     test1
    8     test2
    9  ')
   10  );
  
  1 ligne créée.
  

  http://download.Oracle.com/docs/CD/B19306_01/AppDev.102/b14259/xdb06stt.htm#sthref987

• Unique constraint on the values in both directions

  I'm looking to create a unique constraint that works in two ways. Say I got a constraint unique in columns 1 and 2. I want it to be impossible for the two lines below the two exist at the same time. Is there a way to do this? I googled around for a while now and I found nothing that works so far.

  Header 1	Header 2
  Dog	CAT
  CAT	Dog

  Hello

  You can create an index based on a single function:, like this:

  CREATE UNIQUE INDEX table_x_header_1_header_2

  ON table_x (LESS (header_1, header_2)

  More LARGE (header_1, header_2)

  );

  How will you use these values?  You might be better to simply create a regular old unique constraint, but also have a CHECK constraint to ensure that header_1<= header_2. ="" that="" way,="" when="" you="" want="" to="" search="" for="" the="" combination="" ('cat',="" 'dog')="" you="" won't="" have="" to="" search="" for="" ('dog',="" 'cat')="">

• Unique constraint in the form of master detail error

  Hi all

  I need help, the following requirement.

  I have a master detail form developed on master-child table. the tables have the composite key.

  Old masters has a composite key on columns (A, B)

  Children table has a composite key on columns (A, B, C)

  Child block look something like below

  C       A          B

  10 AAA 1000

  20 1300 BBB

  30 CCC 1400

  40 DDD 1200

  Increments of column C with 10 for each record, and if a new record is insert in intermediaries the records it is incremented to 5.

  My requirement is when an end user attempts to insert record between 20 and 30 or 30 and 40 and clicks on save, the value of the C column must regenerate as shown below

  C       A          B

  10 AAA 1000

  20 1300 BBB

  XXX 30 900

  40 CCC 1400

  50 DDD 1200

  Button Save I wrote the following code

  Declare
    ln_Count NUMBER :=0;
    ln_c number :=0
    cursor c1 is
    select c
    from child
    where a=:child.a
    and b=:child.b
  Begin
    Go_Block('Child');
    First_Record;
    LOOP
    ln_Count:= ln_Count+10;
    :child.C := ln_Count;
    EXIT When :System.Last_Record = 'TRUE';
    Next_Record;
    END LOOP;
  
  
    For c_cur in c1 Loop
    update child
    set c:=ln_c+10
    where a=:child.a
    and b=:child.b 
    and c=c_cur.c
    end loop;
    Forms_DDL('commit');
       
       commit_prc('Commit');  -- We have our own program unit to call commit_form
  
  END;
  

  I tried above in a way because, before approving the changes to the table, I update the existing values in the table of the C column so I would not get unique constraint error.

  When you click the button Save, I get a constraint exception. Hope I made my requirement clear.

  Can someone give me a clue to this implementation.

  Thank you

  malandain

  With this update, all your C-columnvalue became negative. When you post the form thereafter, forms update agaion records one by one the new positive figures. Because the numbers of 'old' in the db are now negative, there will be no violation-UK.

• Unique constraint during the race error collecting statistics of schema

  Hello
  I get this error periodically during execution to collect statistics of schema
  

  In GATHER_SCHEMA_STATS , schema_name= ALL percent= 40 degree = 8 internal_flag= NOBACKUP
  Unable to correctly update the history table - fnd_stats_hist.
  -1 - ORA-00001: unique constraint (APPLSYS.FND_STATS_HIST_U1) violated
  Unable to correctly update the history table - fnd_stats_hist.
  -1 - ORA-00001: unique constraint (APPLSYS.FND_STATS_HIST_U1) violated
  Unable to correctly update the history table - fnd_stats_hist.
  -1 - ORA-00001: unique constraint (APPLSYS.FND_STATS_HIST_U1) violated
  Unable to correctly update the history table - fnd_stats_hist.
  -1 - ORA-00001: unique constraint (APPLSYS.FND_STATS_HIST_U1) violated
  Unable to correctly update the history table - fnd_stats_hist.
  -1 - ORA-00001: unique constraint (APPLSYS.FND_STATS_HIST_U1) violated
  Unable to correctly update the history table - fnd_stats_hist.
  -1 - ORA-00001: unique constraint (APPLSYS.FND_STATS_HIST_U1) violated
  Unable to correctly update the history table - fnd_stats_hist.
  -1 - ORA-00001: unique constraint (APPLSYS.FND_STATS_HIST_U1) violated
  Unable to correctly update the history table - fnd_stats_hist.
  -1 - ORA-00001: unique constraint (APPLSYS.FND_STATS_HIST_U1) violated
  Unable to correctly update the history table - fnd_stats_hist.
  -1 - ORA-00001: unique constraint (APPLSYS.FND_STATS_HIST_U1) violated
  Unable to correctly update the history table - fnd_stats_hist.
  -1 - ORA-00001: unique constraint (APPLSYS.FND_STATS_HIST_U1) violated
  Unable to correctly update the history table - fnd_stats_hist.
  -1 - ORA-00001: unique constraint (APPLSYS.FND_STATS_HIST_U1) violated

  I went thru notes 470556.1 , but I have not applied patch 5876047 according to the note.
  
  I can truncate table FND_STATS_HIST? Is it safe to truncate this table?
  
  Thank you
  ARS
  
  Published by: user7640966 on January 2, 2011 23:58

  Hi Ars;

  If I suggest his prod, make sure you have a valid backup of your system and also raise sr and confirm with oracle support. If you are on the clone or test, such as mention of doc first to backup table FND_STATS_HIST (make sure that you have a valid backup), truncate and repeat the test question

  Respect of
  HELIOS

• Coverage of the issue Image Viewer

  If I have a cover that is composed of a MSO, at least in part, how can I get the cover image in order to correctly display the cover image of the problem in the Viewer? Currently, the Adobe Viewer displays an empty box for the cover of my issue. (see below) We are in the pipeline to register for the professional of DPS. Will there be tools available that allow you to manually assign a cover image? Are there any tools at this stage I know, which will allow me to solve this problem? I also recently got this weird blue lightning bolt image in the corner of the frame. No idea what this means?

  

  You can now apply a manual cover image of in Folio Builder.  Option are at the level of folio (or top) of the generator of folio.  Simply select the folio you want to manually apply a cover for, then select the flyout in the upper right.  Select properties in the passage outside the menu.  You can find options to change the name of your publication and apply some of the coverage.

  Unlike the TOC images that are only 70x70px - cover images should be the size of your publication.  If an ipad verticle publication would have a PNG 72 dpi 786X1024px as his overview of the coverage.

• Case-insensitive unique constraint

  Hi guys,.
  
  Is it possible to create a unique constraint that is case-insensitive
  
  I mean if there is a unique constraint on the name of col
  
  then
  'James' and 'JAMES' must not
  
  
  Kind regards
  
  PAPI

  Create a unique index to the basic function of...

  create unique index uk_name on emp(upper(ename));
  

• Unique constraint violation error

  Hi all
  
  I have a procedure called - FHM_DASHBOARD_PROC which inserts data into a table called FHM_DASHBOARD_F retrieve records in multiple tables. However, for a particular type of record, these data are not inserted because of the Unique constraint violation
  
  the procedure is:
  

  create or replace
  PROCEDURE FHM_DASHBOARD_PROC AS
  
  DB_METRICS_CNT1Z number;
  --V_PODNAME varchar2(10);
  V_KI_CODE_DB_STATSZ varchar2(50);
  V_ERRORSTRING varchar2(100);
  
  --CURSOR PODNAME_CUR IS SELECT PODNAME,SHORTNAME FROM CRMODDEV.POD_DATA WHERE PODSTATUS_ID=1 AND PODTYPE_ID=1 ORDER BY PODNAME;
  
  
  -- DB STATS
  
  BEGIN 
  
    -- OPEN PODNAME_CUR;
      --   LOOP
        --   FETCH PODNAME_CUR INTO V_PODNAME,V_POD_SHORTNAME ;
          -- EXIT WHEN PODNAME_CUR%NOTFOUND;
  
             BEGIN
             
                   SELECT COUNT(*) INTO DB_METRICS_CNT1Z FROM FHM_DB_METRICS_F A, FHM_DB_D B where A.DBNAME=B.DBNAME and PODNAME=V_PODNAME AND DB_DATE=TRUNC(SYSDATE-1);
                             DBMS_OUTPUT.PUT_LINE('DB_METRICS_CNT1Z :'|| DB_METRICS_CNT1Z);
                             IF DB_METRICS_CNT1Z >0 THEN
                           
                      DBMS_OUTPUT.PUT_LINE('DB STATS');
                                
                     INSERT INTO FHM_DASHBOARD_F(PODNAME,DASH_DATE,KI_CODE,KI_VALUE,KI_STATUS)
                                
                        (SELECT PODNAME, DASH_DATE AS CU_DATE, KI.KI_CODE, NVL(PF.KI_VALUE,0), 
                                                                CASE
                                                                 WHEN PF.KI_VALUE = ki.warning_threshold then 2
                      when PF.KI_VALUE=0 then 0
                      ELSE 1 
                      END  AS ALERT_STATUS
                      
                      FROM 
                      
                      (SELECT PODNAME,DB_DATE AS DASH_DATE,decode(a.stats_last_status,'SUCCEEDED',1,'FAILED',2,'STOPPED',2,NULL,0) KI_VALUE from  
                      FHM_DB_METRICS_F a,fhm_db_d b where a.dbname=b.dbname and podname='XYZ' and db_date=TRUNC(SYSDATE-1) and dbtype='OLTP')PF,
                      FHM_KEY_INDICATOR_D KI where PF.PODNAME=KI.POD_NAME AND KI.TIER_CODE=3 AND KI.KI_NAME='DB_STATS'
                      AND (PF.PODNAME,TRUNC(PF.DASH_DATE),KI.KI_CODE) NOT IN (SELECT PODNAME,DASH_DATE,KI_CODE FROM FHM_DASHBOARD_F)); 
                               COMMIT;
                   
                           ELSE
                                  SELECT KI_CODE INTO V_KI_CODE_DB_STATSZ FROM FHM_KEY_INDICATOR_D WHERE POD_NAME=V_PODNAME AND KI_NAME='DB_STATS';
                                   DBMS_OUTPUT.PUT_LINE('V_KI_CODE_DB_STATSZ :'||V_KI_CODE_DB_STATSZ);
                                   INSERT INTO FHM_DASHBOARD_F(PODNAME,DASH_DATE,KI_CODE,KI_VALUE,KI_STATUS) VALUES(V_PODNAME,TRUNC(SYSDATE-1),V_KI_CODE_DB_STATSZ,0,0); 
                                   COMMIT; 
                                   
                           END IF;
                          
       EXCEPTION
                          WHEN OTHERS THEN
                          V_ERRORSTRING :='INSERT INTO FHM_DASHBOARD_F_ERROR_LOG(POD_NAME,KI_NAME,ERRORNO,ERRORMESSAGE,DATETIME) VALUES
                 ('''||V_PODNAME||''',''DB_STATS'','''||SQLCODE||''','''||SQLERRM||''',SYSDATE)';                         
                 EXECUTE IMMEDIATE  V_ERRORSTRING;
                          COMMIT;
            END;
  
        --END LOOP;
    --CLOSE PODNAME_CUR;
  
  
  END;
  
  
  END FHM_DASHBOARD_PROC;

  and the table where data integration is
  

  CREATE TABLE "CRMODDEV"."FHM_DASHBOARD_F"
    (
      "PODNAME" VARCHAR2(25 BYTE) NOT NULL ENABLE,
      "DASH_DATE" DATE,
      "KI_CODE"   NUMBER NOT NULL ENABLE,
      "KI_VALUE"  NUMBER,
      "KI_STATUS" NUMBER,
      CONSTRAINT "FHM_DASHBOARD_F_DATE_PK" PRIMARY KEY ("DASH_DATE", "PODNAME", "KI_CODE") USING INDEX PCTFREE 10 INITRANS 2 MAXTRANS 255 NOLOGGING COMPUTE STATISTICS STORAGE(INITIAL 4194304 NEXT 1048576 MINEXTENTS 1 MAXEXTENTS 2147483645 PCTINCREASE 0 FREELISTS 1 FREELIST GROUPS 1 BUFFER_POOL DEFAULT) TABLESPACE "CRMODDEV_IDX" ENABLE,
      CONSTRAINT "FHM_DASHBOARD_F_KI_CODE_FK" FOREIGN KEY ("KI_CODE") REFERENCES "CRMODDEV"."FHM_KEY_INDICATOR_D" ("KI_CODE") ENABLE
    )
    PCTFREE 10 PCTUSED 40 INITRANS 1 MAXTRANS 255 NOCOMPRESS NOLOGGING STORAGE
    (
      INITIAL 3145728 NEXT 1048576 MINEXTENTS 1 MAXEXTENTS 2147483645 PCTINCREASE 0 FREELISTS 1 FREELIST GROUPS 1 BUFFER_POOL DEFAULT
    )
    TABLESPACE "CRMODDEV_TBL" ENABLE ROW MOVEMENT ;

  the constraint primary key is FHM_DASHBOARD_F_DATE_PK and is on 3 columns of the table, DASH_DATE, PODNAME, KI_CODE
  
  
  
  And it's the query used in the procedure to insert the data into the table
  

  (SELECT  PODNAME, DASH_DATE AS CU_DATE, KI.KI_CODE, NVL(PF.KI_VALUE,0), 
                                 CASE
                                 WHEN PF.KI_VALUE = ki.warning_threshold then 2
  when PF.KI_VALUE=0 then 0
  ELSE 1 
  END  AS ALERT_STATUS
  From 
  (Select  Podname,Db_Date As Dash_Date,Decode(A.Stats_Last_Status,'SUCCEEDED',1,'FAILED',2,'STOPPED',2,Null,0) Ki_Value From  -- Added Distinct
  FHM_DB_METRICS_F a,fhm_db_d b where a.dbname=b.dbname and podname in ('XYZ') and db_date = TRUNC(SYSDATE-2) and dbtype='OLTP')PF,
  Fhm_Key_Indicator_D Ki Where Pf.Podname=Ki.Pod_Name And Ki.Tier_Code=3 And Ki.Ki_Name='DB_STATS'
  And (Pf.Podname,Trunc(Pf.Dash_Date),Ki.Ki_Code) Not In (Select Podname,Dash_Date,Ki_Code From Fhm_Dashboard_F));

  It gives * record * 2 suite
  ---------------------------------------
  XYZ JANUARY 20 12 2521 1 1
  XYZ JANUARY 20 12 2521 1 1
  
  It gives the Unique constraint violation error when inserting. Then, I changed in the above insertion code by adding a distinct clause. Once the query gives only a SINGLE record accordingly. However, this record is not be inserted into the table and give the same error.
  
  Now the question is how should I insert that record into the table with success?
  
  
  If the message is too long, however, I gave you the real structure of the object or procedure and error.
  
  Thank you in advance.

  When you have 5 columns in the game adding THAT SEPARATE is n ot solution that you can still get the same error once.

  Check the target table if the data exists before inserting... If this is not the case, check the structure of the table for a unique constraint created on other columns.

  select *from 
  where
  DASH_DATE=date '2012-01-20'
  and PODNAME='XYZ'
  and  KI_CODE=2521;
  

• Adding a UNIQUE CONSTRAINT to an existing column with duplicate values

  Oracle Forums Hello, I have a table that contains rows 11 901. I tried to define the UNIQUE constraint on the column of xcode, but encountered an error: the column already contain duplicates! I rescued following SQL 'SELECT COUNT (*) FROM States;' the result is 11 901 and 'SELECT COUNT (DISTINCT (xcode)) FROM States;' the result is 11 680. So to enforce this unique key I have to remove the 221 lines. Please how can I do this?

  REMOVE duplicates...

  For example, as

  delete from your_table t
  where rowid <
     (
     select max(rowid)
     from your_table r
     where t.unique_column = r.unique_column);
  

  Thne create the constraint.

• Unique constraints

  I want to add a single validator to a feature attribute using 'list type of validator', the attribute is not the primary key.
  
  I'm following the userid not in userid viewobject.
  
  is this true?

  Hello Mohamed,

  to add a unique constraint on the entity object, you can add alternateKey "you can find it in the tab general entity ' of your entity attribute that you want to be unique and then adds unipue key validation 'entity level validation' and choose your secondary key created, then write failure management message

  Kind regards
  Karim Hasan

• How can I create a constraint on the combination of four columns...

  Dear Guru,

  I have a question... I created the table with columns like "CCode', 'Size1', 'Size2', 'Sch1', 'Sch2', 'Description', 'CCdate '.

  Here I wanted to create a unique constraint on the combination of four columns "CCode', 'Size1', 'Size2', 'Sch1', 'Sch2.

  My requirement is that I don't want to allow duplicate records in the table for the four columns only.

  for example: "CC123", 10, 25, S110, S250,.

  If the new record comes with the same data. Then, I do not want to insert this record.i want to get a constraint voilated error.

  How can I create a constraint on the combination of four columns...

  Pls help me on this issue...

  Kind regards

  Shitab...

  I suggested already here the syntax,

  ALTER table your_table

  Add constraint cons_name unique (col1, col2, col3, col4, col5);

  And don't call me 'Sir '.

  See you soon!

• Name of the PK, unique constraints and to support the index

  I want to have my primary key constraint and index support share of the same name, IE:

  CREATE UNIQUE INDEX MYTABLE_PK ON MYTABLE(...);
  ALTER TABLE MYTABLE ADD CONSTRAINT MYTABLE_PK PRIMARY KEY(...);

  Without definition explicit a unique index using the relational model, the generated DDL added 'X' for the name of the index:

  CREATE UNIQUE INDEX MYTABLE_PKX ON MYTABLE(...);
  ALTER TABLE MYTABLE ADD CONSTRAINT MYTABLE_PK PRIMARY KEY(...);

  I tried to add an index unique explicit to the table, but he changed the name (adds "v1") when I leave the table editor:

  CREATE UNIQUE INDEX MYTABLE_PKv1 ON MYTABLE(...);
  ALTER TABLE MYTABLE ADD CONSTRAINT MYTABLE_PK PRIMARY KEY(...);

  I have the same problem with index & unique constraints.
  
  Issues related to the:
  Can I generate DDL with name matching? "v1" thing seems unlikely, he doesn't want not myself save the definition as I want.
  Where are the transformations of naming for this location? I found tools, preferences, and Data Modeling/naming Standards/Templates but this nugget does nto seem to be there.
  
  Thank you.

  Hi Mike,.

  The Production data release model 3.1 has been updated to allow constraints unique and primary and their indexes share the same name.

  David

• Index naming standards does not and unique constraints

  I found yet another question of naming standards

  I have tried to create a unique constraint as a normal index via the unique constraints and indexes in Properties of Table with the assumption that it will use the design properties of models.  This isn't.

  

  As noted in the image of the model above, my Unique constraint model is {table} _ {columns} lancement_remarques

  and my model of Index idx _ {columns} {table}.  Yet, when I try to create the Unique constraint, it creates the naming convention in names like CUSTOMER_ADDRESS__UK (2 lines of underscore?) as shown below.

  

  My assumption is that he needed a column, so I added the column and also applied the rules naming - nothing.

  

  Is my wrong assumption on these constraints being appointed through the models?  If this is not the case, what naming rules is in this context?

  The same behavior is evident when you try to create index.

  I get not all comments on my posts.  Are these bugs or just user error?

  Hello

  Thank you to report the problem, I logged a bug. You can get 'Rules of naming' works properly if you press the button 'Apply' before that.

  I get not all comments on my posts.

  I don't think that anyone (or any job) has been ignored on this forum. Depending on the complexity of the problem and our current commitment (other urgent tasks, holidays, time zone), you can get answer almost immediately or after a certain time.

  It is useful for us, if you mark your messages as replied if you get the right answer.

  Philippe

• Indexes and UNIQUE constraints

  For a TEST table (col1, col2, col3,...), I put the UNIQUE constraint as follows:
  
  ALTER table TEST add constraint test_uniq UNIQUE col1, col2, col3);
  
  It is said that when the UNIQUE constraint is created, ORACLE also creates an index on (col1, col2, col3) automatically. But sometimes, I use only one of the columns in the WHERE clause as col1 = xxx, or col2 = yyy.
  
  Create separate indexes, one for col1 and col2? I think that even if the creation of the UNIQUE constraint also created an index. But this index is a composite index that is for the dosage of col1, col2 and col3 simultaneously (is that correct)? If so, create an index for col1 and col2 will be necessary?
  
  
  
  Thank you for helping.
  
  Scott

  If there is an index on (col1, col2, col3) and ask about col1, the index will be used.

  If you have questions about col2, it can (index skip scan) or maybe not.

  If you ask about col3 then it will not be used.

  So if you think that there will be queries with col3 in where clause and they can benefit from an index, you can create it.

• Unique index or Unique constraint

  Hi all
  
  I am a student of Oracle SQL Expert Certification. At one point in the book, speaking of the clues, the author says that a unique index is not the same a unique constraint. However, it does not explain why they are two different things.
  
  Could someone clarify the difference between the two, please?
  
  Thank you very much
  
  Valerio

  A constraint has a different meaning for an index. It gives the optimizer more information and allows you to have foreign keys on the column, then that is not a unique index.

  for example:

  SQL> create table t1 (col1 number, col2 varchar2(20), constraint t1_uq unique (col1));
  
  Table created.
  
  SQL> create table t2 (col1 number, col2 varchar2(20));
  
  Table created.
  
  SQL> create unique index t2_idx on t2 (col1);
  
  Index created.
  
  SQL> create table t3 (col1 number, col2 number, col3 varchar2(20), constraint t3_fk
    2                   foreign key (col2) references t1 (col1));
  
  Table created.
  
  SQL> create table t4 (col1 number, col2 number, col3 varchar2(20), constraint t4_fk
    2                   foreign key (col2) references t2 (col1));
                   foreign key (col2) references t2 (col1))
                                                     *
  ERROR at line 2:
  ORA-02270: no matching unique or primary key for this column-list
  

  It's like saying ' what is the difference between a Chair and a Chair? They both allow you to sit! »