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
Tags: Database
Similar Questions
-
Refresh the Materialized View constructed from an external table commit?
Is it possible to create a materialized with Refresh view on commit built from an external table?
I think the answer is "no, because there is no way for the outer table report to the view materialized it has been changed," but I would like to be sure before I tell my client who has requested the opportunity to do this (or, Alternatively, to learn how Oracle hoops I have to cross in order to operate).
I can create a Refresh on demand, it is not a question of not having the necessary permissions to create the materialized view itself.No, you can't. The outer table is not modified in a transactional way and there no materialized view logs, so there is no event to hang in and no delta to apply.
However, you can use dbms_scheduler observer file that will ask for the presence of a file and load the data in a table or refresh a materialized view based on the external table.
Justin
-
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 helpSorry, 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 -
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:
ROWID
materialized 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.
-
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.
-
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
-
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 XPL/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 KINGPL/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.
-
Windows 7 does not refresh the folder views
I have the following problem:
Windows 7 does not automatically refresh the folder view (until I have updated manually by pressing F5) after the following file operations:
Create/delete/rename/move files or foldersFinal version of Windows 7 Professional, international English version. No upgrade, clean installation.
It seems to me that it is a delay in my case: if I wait about 30 seconds, the updating is done automatically. There are shared folders on volume.
I made the following points:
-removed IconCache - did not help
-Reset - folder views did not help
-off to the discovery network and file sharing - did not help
-Made a clean boot - did not help
-a ran sfc - not found any violation
-new user created account - did not help
-updated the BIOS with the latest version - did not help
-updated the VGA driver to the latest version - did not help
-disabled the indexing of files - did not help
-run Windows 7 Mode safe mode (without network): it seems that the problem does not occurI could be satisfied with Windows 7, but this question is terribly boring cause I work with a large number of files per day.
Could someone help me?
I had the same problem recently. Here's what I discovered, FWIW:
- After reading all of the above, it seems that, at the base, this is related to the shell of the user of Windows interface and how he tries to 'reach out' to other systems. Fixes disable the Windows Client, disabling home groups, disable sharing of files, etc.
- I discovered that I have the problem that in some folders. For example, if I try to create a folder in the my DOCUMENTS folder, the problem occurs, but if I create the folder in a random folder on drive C: (e.g.. C:\MyTest), no problem!
- I discovered that the folder appears finally - it takes 30 seconds. By pressing F5, I was "rush" of the process. It also sounds like a kind of thing network client timeout.
I wanted to start with the easiest, lowest impact. It worked:
- I opened the COMPUTER and removed a "network connection" that pointed to a server that is not currently available.
That solved the problem completely.
Dan Holme, Intelliem
-
Hello
I had created a materialized view, it refreshes every 3 minutes. At the end of 3 minutes next time we are accessing the old records of materialized view should be deleted. Can someone help me with this query...
create or replace materialized view deptd_mvu refresh fast on commit start with sysdate next sysdate + 3/(60*24) as select * from deptd;
969052 wrote:
No, my query shows all data are there is no error in my query? can u help me# It is not a mistake on your part of the implementation or Oracle. Error lies in understanding.
Materialized view appeared in SELECT * FROM DEPT; So, it must take all the data that are available in the Dept table each time it is regenerated.
What you intend to do is force the MView to choose the data "Modified" of table DEPT. Is not possible, unless you have some distinctive sign that the MView should be checked.
For Eg :-(just an idea that I did not test this)
Adding another column to identify records updated the: -.
alter table dept add is_modified varchar2(1) default 'N';
MView create instruction me altered as
select * from dept where is_modified = 'Y';
Write a trigger that sets the column IS_MODIFIED 'Y', each time that a record is inserted or updated. Don't worry about the deleted records (if this isn't a Soft Delete) as MView does not see records that are not present in the master table.
You simply need to ensure that, whenever the MView is refreshed, the IS_MODIFIED the Department table must be set to 'n', so that it does not display a false positives.
-
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 youORA-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 youSee 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...
-
Do not to use the materialized view
I wonder if we've already created a materialized view, can we prefer not to use this point of view, materialized for a query? I want to say can we determine if a query uses MV and other queries don't use MV? Thank you.
Hello Indra,
I'm not completely sure about that, but you can read (with examples) concerning the indications- NO_REWRITE and REWRITE
Text over the doc links:
Council of REWRITING:
The
REWRITE
Council instructs the optimizer to rewrite a query regarding the materialized views when possible, regardless of cost. Use theREWRITE
trick with or without a display list. If you useREWRITE
with a view list and the list contains an eligible materialized view, then Oracle uses this view regardless of its cost.Tip NO_REWRITE:
The
NO_REWRITE
Council tells the optimizer to disable the rewrite of the query to the query block, of the substitution of the definition of the parameterQUERY_REWRITE_ENABLED
.Be aware! -The
NOREWRITE
suspicion has been deprecated. Use theNO_REWRITE
hint instead.Read here: setting QUERY_REWRITE_ENABLED
-Nordine
-
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
Materialized view created.
2 activate the rewrite of the query as
3. select count (*), sum (quan_sold), sum (amt_sold) of the sale;
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 querySQL > select count (*), sum (quan_sold), sum (amt_sold) from the sale.
COUNT (*) SUM (QUAN_SOLD) SUM (AMT_SOLD)
6000000 12000000 720480000
Elapsed time: 00:00:30.54SQL > 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: 00:00:01.45SQL > select count (*), sum (quan_sold), sum (amt_sold) from the sale.
COUNT (*) SUM (QUAN_SOLD) SUM (AMT_SOLD)
6000000 12000000 720480000
Elapsed time: 00:00:00.01Please 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.
Maybe you are looking for
-
appointment from one to the other
How to make an appointment for a session? I paid for a year and he was only 6 months, so I'm still good. I can't find anywhere how to register for it. Thanks for your help.
-
Well, as I mentioned above, layout of cards that bothers me in game of hearts of windows 7.
-
M6 sleekbook: HP Envy M6 Sleekbook license key
I need to find my product key for license/because I'm spending in an SSD instead of HARD drive it came with and you need to reinstall windows 8 on the same machince. My HP envy sleekbook M6 came with a preinstalled windows version. Where and how ca
-
BlackBerry Smartphones Exchange messaging solutions
Hello I have an OWA email and I got this setup on BIS, I want to buy a solution such as the one on www.mailstreet.com. When I've buy the solution will I need a password to activate as BES? My IT Department will have to do something? Any answer will b
-
Hey there I have a problem with writing a script. Why do not the code below?app.activeDocument.artLayers.add)app.activeDocument.artLayers [0] .kind = LayerKind.VIBRANCEError: You cannot change the text layer or the normal.In photoshop-cc-javascript-r