Refresh the Materialized View constructed from an external table commit?

Similar Questions

• Order in which the rows are returned from an external table

  Hello
  Anyone know if I can count on the rows returned in the order with a selection of Ext_table.
  For example:
  
  SELECT * FROM MY_EXT_TAB
  
  Where MY_EXT_TAB is a file read
  1
  2
  3
  
  The query will return to the top of the file down, that is to say 1-3.
  
  Thank you very much.

  Hello

  To get the number of the record since the beginning of the file, you can use the MASS_ADDITION_ID parameter in the external Table definition:

  http://download.Oracle.com/docs/CD/B19306_01/server.102/b14215/ldr_field_list.htm#sthref1264

  You define a column:

   RECNUM
  

  Then, in your application, you can use the operator order of this column.

  In this way, you ensure that you always comply with the registration order in the file.

  Hope this helps.
  Best regards
  Jean Valentine

• refresh the materialized view, but skip delete

  I have a main table named DATA with mview log created on this subject.
  
  DATA_MVIEW is created in the select * data.
  
  For some reason, I want to update DATA_MVIEW every hour, but to only UPDATE/INSERT, skip DELETE action.
  
  A way to achieve that is to write additional code:
  1 detect records looking into MLOG$ _DATA (Journal mview) worth $$ DMLTYPE is D.
  2. pull these records in a separate temporary table.
  3 Refresh DATA_MVIEW
  4. Insert the records from the temporary table in DATA_MVIEW.
  
  My question is "is there a better, simpler way to ignore DELETE them when updating MVIEW?
  
  Thank you very much and waiting for tips Rewards points!

  There is another convoluted option:
  1. create an ON DELETE trigger on the DATA table that copies each line removed in a shadow / historical table
  2 update the MV
  3. create a view (not a MV) which is a Union All of the table shadow history with the MV
  4 refer to this view when you want to that 'all', the MV lines when you want 'alone that does not exist' reference lines

  Of course, if your MV is equipped with filters (WHERE clause) that is defined as a subset of the DATA table, you must also check that the shadow/history table also applies the same filters so that it fits with the MV.

  Hemant K Collette

• Refresh of the materialized view; Process flow

  I was wondering if anyone has used process flow to refresh the materialized view.
  
  I'm trying to use a process flow for it, either run something similar to below
  EXECUTE Dbms_refresh.Refresh ('"ODW_SRC".) "MV_SERVICE_DAILY_AUDIT" ');
  
  I try to avoid using the Scheduler of DB because I want to make sure that the process flow is not conflict with the update of a materialized view possible cause conflict more execution time of the work expected will refresh window.
  
  I guess I could use a transformation and build. but I was wondering if there is an easier way in the execution of it just line... an idea
  
  Thanks in advance for your help

  Sorry, I think that the term OWB is post mapping process, its actually an operator in an OWB mapping where you can add a procedure for example call. The procedure can do pretty much what he wants.

  See you soon
  David

• The Materialized View - ORA-12052: is unable to fast refresh materialized view

  Hello

  I was hitting my head all day trying to create materialized views. I have made some progress, but have hit a brick wall, unfortunately!

  Basically, I have been invited to take a view and see if I can get the benefits of performance by transforming all or part of it in materialized views. Because the underlying tables of the config is updated quite frequently, I want to fast refresh materialized views on commit. However, when I try to create a materialized view containing an outer join in an aggregated materialized view table, I get ORA-12052: is unable to fast refresh materialized view.

  I went through the documentation and also Rob van Wijkvery useful series of blogs on the topic (especially http://rwijk.blogspot.co.uk/2009/09/fast-refreshable-materialized-view.html) but have not found anything that matches. Maybe I missed something somewhere along the line, or maybe I'm asking just something completely impossible?

  My db is 11.2.0.2.

  Here's the test scripts, I've worked with that:

  drop materialized view test1_test2_mv;
  Drop materialized view test2 journal;
  drop table test2;
  Drop materialized view test1_mv newspaper;
  drop materialized view test1_mv;
  Drop materialized view test1 journal;
  drop table test1;

  create table test1 (identification number,
  type varchar2 (10),
  number of Val,
  update_time date,
  constraint t1_pk primary key (id, type, val));
  
  Insert into test1
  Select 1, 'a', 1001, sysdate - 10/24 Union double all the
  Select 1, 'b', 1003, sysdate - 9/24 Union double all the
  Select 1, 'c', 1002, sysdate - 8/24 Union double all the
  Select 1, had ', 1004, sysdate - 7/24 Union double all the
  Select 1, 'e', 1005, sysdate - 6/24 Union double all the
  Select 1, 'c', 1006, sysdate - 5/24 Union double all the
  Select 2, 'a', 1002, sysdate - 4/24 Union double all the
  Select 2, 'b', 1005, sysdate - 3/24 Union double all the
  Select 3, 'a', 1001, sysdate - 2/24 Union double all the
  Select 3, 'c', 1006, sysdate - 1/24 Union double all the
  Select 3, 'e', 1008, sysdate - 2/24 Union double all the
  Select option 4, has ', 1004, sysdate - 3/24 Union double all the
  Select 5, 'b', 1002, sysdate - 4/24 Union double all the
  Select 5, 'g', 1001, sysdate - 5/24 Union double all the
  Select 6, 'h', 1004, sysdate - 6/24 Union double all the
  Select 7, 'b', 1007, sysdate - 7/24 Union double all the
  Select 7, had ', 1001, sysdate - 8/24 double;

  commit;

  Select * from test1;

  
  CREATE MATERIALIZED VIEW LOG ON test1
  WITH rowid, primary key (update_time)
  including the new values;

  
  Test1_mv CREATE MATERIALIZED VIEW
  IMMEDIATE CONSTRUCTION
  COOL OFF QUICKLY ON COMMIT
  Did YOU SELECT id,
  MAX (case when type = "there" end of val) THAT col_a,.
  MAX (case when type = 'b', then val end) AS col_b,.
  MAX (case when type = 'c' then end val) AS col_c,.
  MAX (case when type = ' then end of val) AS col_d,
  MAX (update_time) AS update_time
  OF test1
  WHERE TYPE in ('a',
  « b »,
  « c »,
  a ')
  GROUP BY id;

  CREATE MATERIALIZED VIEW LOG ON test1_mv
  WITH rowid
  including the new values;

  
  create table test2 (identification number,
  col2 number,
  COL3 varchar2 (10),
  number of COL4,
  constraint t2_pk primary key (id));
  
  Insert into test2
  Select 1, 1, 'bob', 1 double Union all
  Select 2, 1, "sue", 1 double Union all
  Select 3, 1, 'tom', 1 double Union all
  Select 4, 1, 'jay', 1 double Union all
  Select 5, 1, 'art', 1 double Union all
  Select 6, 1, 'kay', 1 double Union all
  Select 7, 1, 'max', 1 double Union all
  Select 8, 1, 'tim', 1 double Union all
  Select 9, 1, "liz", 1 from dual;

  commit;

  
  CREATE MATERIALIZED VIEW LOG ON test2
  WITH rowid, primary key
  including the new values;

  
  Test1_test2_mv CREATE MATERIALIZED VIEW
  IMMEDIATE CONSTRUCTION
  COOL OFF QUICKLY ON COMMIT
  LIKE SOME t2.rowid,.
  T1.ID,
  T1.col_a,
  T1.col_b,
  T1.col_c,
  T1.col_d,
  T1.update_time,
  T2.col2,
  T2. COL3
  OF test1_mv t1,.
  Test2 t2
  WHERE (+) t1.id = t2.id; -symbol of outer join is not correctly displayed on the forums without space, grr!

  ORA-12052: is unable to fast refresh materialized view TEST1_TEST2_MV

  Y at - it any way I can get the materialized view fast refresh on commit or I asking the impossible?

  Add t1.rowid:

  SQL > CREATE MATERIALIZED VIEW test1_test2_mv

  2 BUILD IMMEDIATE

  3 QUICK REFRESH YOU COMMIT

  4 AS t2.rowid SELECT rid2,

  5 t1.rowid rid1,

  6 t1.id

  T1.col_a 7,.

  T1.col_b 8,.

  T1.col_c 9,.

  T1.col_d 10,

  T1.update_time 11,

  T2.col2 12,

  13 t2.col3

  14 OF test1_mv t1,

  15 test2 T2

  16 WHERE t1.id = t2.id

  17.

  Materialized view created.

  SQL > select * from test1_test2_mv

  2.

  RID2 RID1 ID COL_A, COL_B, COL_C COL_D UPDATE_TIME COL2 COL3

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

  AAAYB6AANAAAANDAAA AAAYB/AANAAAAN/AAA 1 1001 1003 1006 1004 25 / 06 / 2014 12:54:16 1 bob

  AAAYB6AANAAAANDAAB AAAYB/AANAAAAN/AAB 2 1002 1005 25 / 06 / 2014 1 sue 14:54:16

  AAAYB6AANAAAANDAAC AAAYB/AANAAAAN/AAC 3 1001 1006 25 / 06 / 2014 16:54:16 1 tom

  AAAYB/AANAAAAN/AAD AAAYB6AANAAAANDAAD 4 1004 25/06/2014 14:54:16 1 jay

  AAAYB6AANAAAANDAAE AAAYB / AANAAAAN / AAE 5 1002 2014/06/25 13:54:16 1 art

  AAAYB6AANAAAANDAAF AAAYB/AANAAAAN/AAG 7 1007 1009 25 / 06 / 2014 10:54:16 max 1

  AAAYB/AANAAAAN/AAH                                                                                                        1 tim

  AAAYB/AANAAAAN/AAF                                                                                                        1 kay

  AAAYB/AANAAAAN/AAI                                                                                                        1 liz

  9 selected lines.

  SQL > update of test2

  2 set col3 = "fly."

  3 where id = 7

  6 m

  1 line update.

  SQL > validation

  2.

  Validation complete.

  SQL > select * from test1_test2_mv

  2.

  RID2 RID1 ID COL_A, COL_B, COL_C COL_D UPDATE_TIME COL2 COL3

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

  AAAYB6AANAAAANDAAA AAAYB/AANAAAAN/AAA 1 1001 1003 1006 1004 25 / 06 / 2014 12:54:16 1 bob

  AAAYB6AANAAAANDAAB AAAYB/AANAAAAN/AAB 2 1002 1005 25 / 06 / 2014 1 sue 14:54:16

  AAAYB6AANAAAANDAAC AAAYB/AANAAAAN/AAC 3 1001 1006 25 / 06 / 2014 16:54:16 1 tom

  AAAYB/AANAAAAN/AAD AAAYB6AANAAAANDAAD 4 1004 25/06/2014 14:54:16 1 jay

  AAAYB6AANAAAANDAAE AAAYB / AANAAAAN / AAE 5 1002 2014/06/25 13:54:16 1 art

  AAAYB/AANAAAAN/AAH                                                                                                        1 tim

  AAAYB/AANAAAAN/AAF                                                                                                        1 kay

  AAAYB/AANAAAAN/AAI                                                                                                        1 liz

  AAAYB6AANAAAANDAAF AAAYB/AANAAAAN/AAG 7 1007 1009 25 / 06 / 2014 10:54:16 1 rob

  9 selected lines.

• I get "failed to set the refresh attribute COMMIT for the materialized view" when I try to create a MV using a table and another MV

  Experts,

  I'm trying to create a YOUNG refreshable ON COMMIT MV (xyz) using a table (circuit) and quickly updateable on validation MV (abc), but get an error:

  SQL error: ORA-12054: cannot set the attribute ON COMMIT refresh for the materialized view

  12054 00000 - "cannot set the refresh attribute COMMIT for the materialized view.

  * Cause: The materialized view did not meet the requirements for update to

  moment of validation.

  * Action: Specify only valid options.

  1] MV abc
  = MV abc defined as below =.

  CREATE MATERIALIZED view abc_MV

  Immediate CONSTRUCTION

  REFRESH QUICKLY YOU COMMIT using constraints of trust

  WITH ROWID AS SELECT n.*,.

  n.ROWID noderowid

  node n

  where n.nodetype in (1610000069,1610007267);

  
  

  -Above works OK and MV connect you on table node is created successfully

  =====================================================

  [ 2] Circuit Board

  ======================================================

  CREATE MATERIALIZED VIEW LOG ON Cramer.Circuit WITH SEQUENCE, ROWID ( ) -all columns of table ofcircut parentheses

  INCLUDING THE NEW VALUES;

  -More top works OK and MV connect you on table circuit is created successfully

  ======================================================
  

  
  

  
  

  [3] trying to create MV xyz
  

  ======================================================

  CREATE MATERIALIZED VIEW LOG ON cramer.abc_MV WITH SEQUENCE, ROWID ( ) -all columns of abc_MV brackets

  INCLUDING THE NEW VALUES;

  -Above works OK and log on ABC MV MV gets created successfully

  -Problematic step below

  Xyz_MV CREATE MATERIALIZED VIEW

  IMMEDIATE CONSTRUCTION

  REFRESH QUICKLY YOU COMMIT using constraints of trust

  AS

  SELECT c., c.rowid circuit_rowid, n.rowid tr_rowid

  the circuit c, abc_mv n

  where circuit2startnode = n.nodeid

  and c.rpplanId = n.rpplanId;
  ==========================================================

  Clues on how to solve this problem and make quickly updatable ON Commit MV xyz

  Thanks in advance.

  Chanchal,

  If you can read my original post carefully you may have noticed that all these restrictions will not apply in my case.

  All,

  In any case I found the solution to my problem.

  There are a few additional restrictions for materialized views multilayer

  Additional Restrictions for master materialized views

  The following types of materialized views may not be masters of editable materialized views:

  • ROWIDmaterialized views
  • Complex materialized views
  • Read-only materialized views

  I've updated the underlying MV abc below and everything worked like a charm

  CREATE MATERIALIZED view abc_MV

  Immediate CONSTRUCTION

  REFRESH QUICKLY YOU COMMIT using constraints of trust

  IN SELECT

  n.*, n.rowid noderowid, nt.rowid nodetyperowid

  the node n, nodetype_m nt

  where n.node2nodetype = nt.nodetypeid

  and nt.nodetypeid in (1610000069,1610007267);

  Note: To ADD a join without which I was getting error below (although had primary key on the table of the node)

  SQL error: ORA-23415: materialized view log for "NODE" does not save the primary key

  23415 00000 - "view the log for materialized \"%s\".\"%s\"does not save the primary key.

  * Cause: A primary key materialized view is refreshed quickly, but the

  The materialized view log does not record the primary key information.

  * Action: Use CREATING MATERIALIZED VIEW LOG... Command to add a PRIMARY KEY to

  start recording of the primary key information in the materialized view

  Newspaper.

• How to improve the materialized view Refresh speed?

  Hello
  
  
  Are there tips to improve the speed of refresh of the materialized views?
  All documentation or advice are appreciated!
  
  Thank you!

  Agree with S_Lindenmayr, if possible, the fast refresh should be used to speed up the update because it syncs MV with only the changes since the previous update (instead of the refresh). To implement the Fatst update, fortunately, with 10 g +, Oracle provides a counselor with the TUNE_MVIEW procedure. Step by step to find in week 12 of the Top 20 features the famous Arup Nanda 10 g for the series of DBA http://www.oracle.com/technology/pub/articles/10gdba/week12_10gdba.html

  Tarraf

• How to understand where are the data in a materialized view, coming from

  HI: when I run select NAME, OWNER of dba_mview_refresh_times, I see a number of materialized views. How can I find more information on this view it's source data and fields. The source in a different database table has changed. But the view on my database where the materialized view has not changed. I want to confirm origin of data in this view
  
  TIA
  Ravi

  Take a look at the column of the QUERY to the DBA_MVIEWS view.

• Trigger on the materialized view

  Hello

  I have the scenario based (Database 11 g):

  There is a view materialized (PERSON), which contains the ID and NAME fields. This MV is update daily with a fast refresh.

  I have a second array (NAMES), with ID and NORM_NAME. This table contains the name of the person, without special characters.

  For example, for recording / * 1 BJORN * / in the PERSON table

  I would check * 1 BJORN * / in table NAMES.

  
  

  Problem is how to fill the NAME table after the filling of the materialized view.

  I used a trigger AFTER INSERT or update, as described below, but even if I update the master table (for this purpose, update the MV), I have only to trigger inserts.

  
  

  Is there a way to implement a trigger "after update" on a materialized view, or do I need another approach?
  

  
  

  /*

  
  

  create or replace TRIGGER TRG_TESTE_MV

  AFTER INSERT OR UPDATE ON THE PERSON

  REFERENCING OLD AS OLD AGAIN AS NEW

  FOR EACH LINE

  BEGIN

  IF THE INSERTION

  INSERT THE NAMES

  VALUES

  (: NEW.id,:NEW.NAME);

  END IF;

  IF THE UPDATE CAN

  UPDATE OF NAMES

  SET NAME =: NEW.NAME WHERE ID =: NEW.id;

  END IF;

  END;

  */

  Thanks for any help

  Your trigger fires, but I doubted that you will be satisfied with the results. You really need to understand how to refresh process works before you begin creating triggers of MV:

  SQL > create table emp1 in select * from EMP
  2.

  Table created.

  SQL > create materialized view emp1 with rowid journal
  2.

  Materialized view log that is created.

  SQL > create materialized view emp1_mv
  2 fast refresh
  3 on request
  4 with rowid
  5 as
  6 select * from emp1
  7.

  Materialized view created.

  SQL > create or replace
  trigger 2 emp1_mv_biudr
  3 before inserting
  4 or update
  5 or delete
  6 on emp1_mv
  7 for each line
  Start 8
  9 insert then dbms_output.put_line ('INSERT' |: new.ename); end if;
  10 if the deletion then dbms_output.put_line ('REMOVE' |: old.ename); end if;
  11 end;
  12.

  Trigger created.

  SQL > insert
  2 in emp1 (empno, ename, sal)
  3 values(1,'X',1000)
  4.

  1 line of creation.

  SQL > validation
  2.

  Validation complete.

  SQL > set serveroutput on
  SQL > exec dbms_mview.refresh ('emp1_mv', 'f');
  INSERTION OF X

  PL/SQL procedure successfully completed.

  SQL > update emp1
  2 set sal = sal + 1
  3 where ename ('King', 'JONES')
  4.

  2 lines to date.

  SQL > validation
  2.

  Validation complete.

  SQL > set serveroutput on
  SQL > exec dbms_mview.refresh ('emp1_mv', 'f');
  INSERTION OF JONES
  INSERTION OF KING

  PL/SQL procedure successfully completed.

  SQL > delete emp1
  2 where in ename ('ALLEN', 'SMITH')
  3.

  2 deleted rows.

  SQL > validation
  2.

  Validation complete.

  SQL > set serveroutput on
  SQL > exec dbms_mview.refresh ('emp1_mv', 'f');

  PL/SQL procedure successfully completed.

  SQL >

  As you can see, refresh MV updates ever. Results update underlying table to remove/insert in MV. That's why your trigger will not give the results that you expected.

  SY.

• Re: view opaque and the materialized view

  Hi Experts,

  I want some clarification of opaque and view view in the physical layer OBIEE materialized

  -> what is the main difference between the opaque view and materialized in the RPD perspective view, we have to do this at the level of the RPD or DB.

  -> I want the list of opaque opinion and materialized in the RPD view how I should do.

  -> How opaque views will degrade the performance and how a materialized view will improve performance at the level of the report.

  -> In scenarios that we use view opaque and the view materialized (if possible with a scenario for the best permanent basis).

  Thanks in advance.

  I want some clarification of opaque and view view in the physical layer OBIEE materialized

  -> What is the main difference between opaque view and create the materialized view in the RPD point of view, we have to do this at the level of the RPD or DB.

  Opaque views is a SQL statement that is defined in the physical layer, OBIEE will use all in the construction of a SQL query. In a way it's not different from a database view, except it is set in OBIEE only. Alternatively, you can deploy an Opaque view, which pushes its definition in the database. Read more about it here: work with physical tables, Cubes and joins - 11 g Release 1 (11.1.1)

  A materialized view (MV) is a database concept where the results of a SQL statement are physicalised like a table, and therefore as OBIEE is a MV is just another physical array

  -> If I want a list of the opaque views and materialized in the RPD view how I should do.

  To find opaque views, use the function «Repository of applications» administration tool Search physical Tables and set up a filter on the Type = Select

  Screenshot: https://www.evernote.com/shard/s16/sh/5c843e47-bff1-4d4b-b847-be98f3a2ec09/cf060a6cd9805f687fa0b5b46f3f0020

  To find materialized views, you will need to query the catalog in your database (for example select object_name, object_type from user_objects where type_objet = "MATERIALIZED VIEW" ;) and compare it to the list of tables in your SPR)

  -> How opaque views will degrade the performance and how a materialized view will improve performance at the level of the report.

  A materialized view is materialized, in other words, the results are already stored in the database. This means usually there will be more efficient because all the joins and aggregations, etc. will be settled in advance.

• fast refresh on MATERIALIZED VIEW

  Oracle 10 g R2 (10.2.0.5)
  
  Scott.mv_test CREATE MATERIALIZED VIEW
  Users TABLESPACE
  NOCACHE
  LOGGING
  NOCOMPRESS
  NOPARALLEL
  IMMEDIATE CONSTRUCTION
  REFRESH THE STRENGTH TO DEMAND
  WITH THE PRIMARY KEY
  AS
  Select...
  
  I this MV, when I do the QUICK refersh as follows, I get the error message
  
  SQL > execute DBMS_MVIEW. REFRESH ('MV_TEST', 'f');
  DBMS_MVIEW BEGIN. REFRESH ('MV_TEST', 'f'); END;
  
  *
  ERROR on line 1:
  ORA-12004: QUICK COOLING can be used to view materialized "SCOTT." "" MV_TEST ".
  ORA-06512: at "SYS." DBMS_SNAPSHOT", line 2251
  ORA-06512: at "SYS." DBMS_SNAPSHOT", line 2457
  ORA-06512: at "SYS." DBMS_SNAPSHOT", line 2426
  ORA-06512: at line 1
  
  But it works with full refresh.
  
  Is this planned, any help would be appreciated.
  
  Thank you

  ORA-12004: REFRESH FAST cannot be used for materialized view "string"."string"
  Cause:      The materialized view log does not exist or cannot be used. PCT refresh is also not enabled on the materialized view
  Action:      Use just REFRESH, which will reinstantiate the entire table. If a materialized view log exists and the form of the materialized view allows the use of a materialized view log or PCT refresh is possible after a given set of changes, REFRESH FAST will be available starting the next time the materialized view is refreshed.
  

  http://ORA-12004.ora-code.com/

• question on the materialized view unregistered on the main site

  Hello
  
  you know how one knows, on the main site, on the existence of a materialized view another site referring to other tables to a primary site. It seems registration is not required.
  
  the site main orcl1: I have a table, and a materialized view log defined on A table.
  another site orcl2: have a link db orcl1 and rapid updatable view SCOTT materialized. A_MVW (create a materialized view A_MVW cool off quickly in select * from A@orcl1)
  
  on orcl1 I perform: exec DBMS_MVIEW. UNREGISTER_MVIEW (mviewowner = > 'SCOTT', mviewname = > mviewsite, 'A_MVW' = > 'ORCL2');
  so the materialized view seems to be correctly set aside (because it no longer appears in: select * from DBA_REGISTERED_MVIEWS ;))
  But, to my surprise, I can still perform refreshes fast on A_MVW, which also remove rows from the materialized view log. So how is site orcl1 always aware of the existence of the materialized view?
  
  It seems that, registered or not to the main site, a materialized view has the same... or is not? where is it stored, on the main site, information about materialized views (especially those of quickly updatable) as local tables reffer?
  
  Thank you

  See DocIDs 258634.1, 67371.1, 1031924.6
  on Oracle's Support website.

  Hemant K Collette

• Difference between the view and the materialized view

  Hi all
  
  Can someone tell me exactly the difference between the view and materialized views?

  Hello

  View:-this is a virtual table means table is there, but in fact is not there...
  see how to create a view...

   create or replace view aaa as select * from emp; 
  

  Now, when we choose the AAA, he will show me all the data that would be returned by running a query "Select * from emp"... Thus, all data will come from table iteself.
  View in itself is nothing but just a Sql statement that is used to create the view, in this case definition is "select * from emp.
  Any update in the database table Emp which is in our case, would automatically result in the view...
  Any changes (all dml) will actually update the base table (conditions apply *)

  Now the materialized view:-this is the same as except that it is not a virtual table... This will be created separately and it will acutally hold the result of the query that is used to create it. Any subsequent changes in the base table only will be included in the opinion of M M view is refreshed...

• Change the definition of the materialized view while maintaining access for users uninteruupted

  Hello

  We have a system report and the need to change the report definition mv access - like to do it without interruption.

  Is this possible?

  the sql behind mv was change picks up so column of another table.

  Have you heard but not used for dbms_redefinition tables

  Thank you

  It is built in the Oracle solution for this one, where you can edit the definition WITHOUT interruption. You can drop the materialized view existing with the clause "save table" and rebuilt the view materialized on 'predefined table'. I googled this example for you

  create materialized view mv1 as select dept , count(*) as cnt from scott.emp;

  We want to change the statement so that only dept more 5 will be calculated

  drop materialized view mv1 preserve table;
  

  Notice that PRESERVE TABLE clause - mv1 table is not droped - single layer mview.

  desc mv1
  

  now, we create the mview with a different query on top of the existing table

  create materialized view mv1 on prebuilt table as  select dept , count(*) as cnt from scott.emp where dept > 5;
  

  Notice that on prebuilt table the mview uses the existing object clause.

  exec dbms_mview.refresh_mview('mv1');
  

  http://StackOverflow.com/questions/18085894/redefine-MATERIALIZED-view-with-no-downtime

  http://Arup.blogspot.com/2009/01/ultra-fast-MV-alteration-using-prebuilt.html

• Elapsed time for the materialized view vs Master table query

  Hello all;
  
  Small confusion about time up for the vs Master materialized view table query
  
  

  SQL > select count (*), sum (quan_sold), sum (amt_sold) of the sale;

  COUNT (*) SUM (QUAN_SOLD) SUM (AMT_SOLD)
  6000000 12000000 720480000
  Elapsed time: 00:00:30.54
  

  SQL > create materialized view mv1
  2 activate the rewrite of the query as
  3. select count (*), sum (quan_sold), sum (amt_sold) of the sale;

  Materialized view created.
  Elapsed time: 00:00:01.45
  

  SQL > select count (*), sum (quan_sold), sum (amt_sold) of the sale;

  COUNT (*) SUM (QUAN_SOLD) SUM (AMT_SOLD)
  6000000 12000000 720480000
  Elapsed time: 00:00:00.01
  
  Please see the three cases "Elapsed Time"...
  
  When comparing other cases.
  1. my query takes long time (30.54), extraction of data from the sale
  2. create a materialized view takes less time (01:45) why?
  
  Source: http://uhesse.com/2009/07/08/brief-introduction-into-materialized-views/

  >
  Small confusion about elapsed time for the materialized view vs Master table query

  SQL > select count (*), sum (quan_sold), sum (amt_sold) from the sale.

  COUNT (*) SUM (QUAN_SOLD) SUM (AMT_SOLD)
  6000000 12000000 720480000
  Elapsed time: 00:00:30.54

  SQL > create materialized view mv1
  2 activate the rewrite of the query as
  3. select count (*), sum (quan_sold), sum (amt_sold) of the sale;
  Materialized view created.
  Elapsed time: 00:00:01.45

  SQL > select count (*), sum (quan_sold), sum (amt_sold) from the sale.

  COUNT (*) SUM (QUAN_SOLD) SUM (AMT_SOLD)
  6000000 12000000 720480000
  Elapsed time: 00:00:00.01

  Please see the three cases "Elapsed Time"...

  When comparing other cases.
  1. my query takes long time (30.54), extraction of data from the sale
  2. create a materialized view takes less time (01:45) why?
  >
  Many queries take less time the second time you run them. After the first performance, there may be many, if not all, lines in the buffer cache. Then the second round will not make any or all e/s physical but will obtain data from the buffer cache.

  Also, you haven't checked that the MV was even used for the second run.

  Drop the MV and make the query several times and means of the time. Then create the MV and do the same thing.