SQL & PL/SQL :: Difference Between View And Materialized View
Apr 26, 2011difference between view and materialized view?
View 1 Repliesdifference between view and materialized view?
View 1 Replieswhat would be the difference between a view and a materialized view? whether DML possible on a view? i think error occurs if DML tried on a view which is a combination of two or more tables, whether DML possible on a materialized view?
View 7 Replies View RelatedWhat is the difference between Materialized view and dblink. When we use materialized view and when we use dblink. In my knowledge mviwes and dblinks are used to retrieve data from remote database.But I am unable to understand when should we materialized views and when should we use dblinks.
View 1 Replies View Relatedthe difference in detail with an example.
View 5 Replies View Relatedwhat is the difference between materialized view and snapshot ?
View 1 Replies View RelatedI have 3 sites which want to be updated as soon as the other one updates its data.(in 5 seconds). So I have chosen multi master solution,sync regardless of the resource consideration.
1-what is the difference between multimaster async and updatable materialized view regardless of resource consuming in multimaster?because in both of them each site can receive and also propagate the data...I just know that in materialized view we can work offline and then apply it manually is there any other thing?
2-I can not understand the difference between multimaster sync and async (considering the 5 seconds,because 5 second is a little time)I mean in this case are they different from each other or not.
can we change the existing materialized view to normal view? if yes how?
View 2 Replies View RelatedI'm trying to create a Materialized View on a remote database from a simple view. The reason is, the data owners don't want to grant explicit tables privileges to external subscribers.
A new schema is created to publish data in the form of a view. I've created mlogs on the master tables, and granted them to the subscriber, but it's still complaining about a missing primary key on the view. A primary key does exist in the master table.
Is there another work around for this situation without having to work inside the data sources' environment?
I have a materialized view "pro_mview",I am trying to refresh the MVIEW by using the following statement.
EXEC DBMS_MVIEW.REFRESH('pro_mview','C');
But I am getting the below error.
*
Error at line 1:
ORA-12008: error in materialized view refresh path
ORA-00942: table or view does not exist
ORA-06512: at "SYS.DBMS_SNAPSHOT", line 2256
ORA-06512: at "SYS.DBMS_SNAPSHOT", line 2462
ORA-06512: at "SYS.DBMS_SNAPSHOT", line 2431
ORA-06512: at line 1
I am able to fetch the data from that materialized view(pro_mview).
I have requirement to create materialized views. The design states to use Complete refresh. Now I am using WITH ROW_ID clause.
1. Question - what are the criteria to decide between WITH PRIMARY KEY & WITH ROW_ID clauses? I referred oracle doc, but couldn't exactly get this.
2. Background - The oracle doc mentions that - Primary key materialized views are the default type of materialized view. The master table must contain an enabled primary key constraint, and the defining query of the materialized view must specify all of the primary key columns directly.
Question - I saw some existing materialized views in my project using WITH PRIMARY KEY clause, but all of the primary key columns are not part of the Select query, but still these views are working fine, how is this possible?
3. Background - The oracle doc mentions that - Rowid materialized views must be based on a single table and cannot contain any of the following:
■Distinct or aggregate functions
■GROUP BY or CONNECT BY clauses
■Subqueries
■Joins
■Set operations
Question - But I have created a Rowid materialized view selecting data from more than one table & defining query involving outer joins. This materialized view got created & getting refreshed (complete refresh). But again this is contradicting with Oracle' statement.
There are 2 databases, database A and database B. Database A is Oracle 11.2.0.2 which runs on linux and Database B is Oracle 11.2.0.2 which runs on windows xp machine. In database A, there are 100's of tables which are being updated every 10 minutes or 15 minutes. For reporting purpose, the developer wants to run report for the tables. But since database A is being updated every now and then, generating reports takes almost 15 to 20 minutes. So the reports can be generated in Database B. Once in a day the database B should have the updated data from database A so that the reports can be generated in database B with less time. What could be the best solution for the database B to have the updated data on daily basis from database A in oracle?
View 3 Replies View Relatedi have created FAST refresh materialized view.it is eligible for FAST refresh because when i executed SELECT * FROM USER_MVIEWS i could see FAST_REFRESHABLE=DIRLOAD_DML and STALENESS=STALE and it is not getting refreshed(through DBA_JOBS). Why it is in STALE status and how to resolve it. and one of my materialized views is in NEEDS_COMPILE status
View 3 Replies View RelatedA scheduler job is there to refresh some materialized views. All the views are run under single job name. Some mviews are not refreshing and those are not refreshing in the next run too.if we run those mviews manually then they are working fine from then . after some days those views which i told before are not refreshing and this happens frequently and i check the job_run_details views also and i am not seeing any errors in that.
View 6 Replies View RelatedI need redefine a Materialized View (add some columns). I try it with:
drop materialized view TCPIP preserve table;
ALTER TABLE TCPIP ADD (SUM_IP_OUT_OF_SEQ NUMBER)
/
ALTER TABLE TCPIP ADD (SUM_IP_OUT_OF_SEQ NUMBER)
/
and than create a new MV:
CREATE MATERIALIZED VIEW TCPIP
ON PREBUILT TABLE USING NO INDEX NEVER REFRESH ENABLE QUERY REWRITE as
SELECT ...
But with Oracle error: ORA-12060: shape of prebuilt table does not match definition query
I check the new MV definition, it is contain the 2 added columns.
Why we can create indexes only on materialized view and not on normal views?
View 8 Replies View RelatedCan u explain the syntax of materialized view??????
View 1 Replies View RelatedHow can we find how much space is used by the materialized view.
View 1 Replies View RelatedI have created a Materialized View (MV) and within the MV DDL have included a statement as per below. However, the MV does not seem to be refreshing on a daily basis. I can see the job in dba_jobs table. So the question, is there some system setting i need to execute or create in order for Oracle to know that it needs to run the Job defined in the dba_jobs table on a daily Basis?
View 8 Replies View RelatedI have created materialized view which hold few million records.Should i have to analyze the view and compute the statistics after i create the materialized view?
Also, just in case i need further indexing, should i have to take the statistics for the table again?
I am running into an issue and trying to ascertain issue. Scenario:I have 2 MV creation scripts. The MV is supposed to get populated by connection from schema to another schema USING DB Links.Basically, SAME HOST, SAME RAC DATABASE, just separate schemas. The MV creations are just hanging. I see NO alert log mentions. I ran a SQL trace and yes,
I see: call count cpu elapsed disk query current rows------- ------ -------- ---------- ---------- ---------- ---------- ----------Parse 0 0.00 0.00 0 0 0 0Execute 1011 1.40 73.80 0 0 0 0Fetch 1010 1.08 317.57 0 0 0 1010------- ------ -------- ---------- ---------- ---------- ---------- ----------total 2021 2.49 391.38 0 0 0 1010 Misses in library cache during parse: 0Optimizer mode: ALL_ROWSParsing user id: 109 (recursive depth: 2) Elapsed times include waiting on following events: Event waited on Times Max. Wait Total Waited ---------------------------------------- Waited ---------- ------------ SQL*Net message to dblink 2022 0.00 0.00 SQL*Net message from dblink 2021 0.46 242.58
Understandable, but when I do a selective query, the results come back pretty much within 5 seconds.DB version is 11.2.0.3. Is there a BUG that I should know about?
Here is a snippet:
CREATE MATERIALIZED VIEW "SCHEMA"."MV_NAME_MV" USING INDEX REFRESH COMPLETE ON DEMAND AS (SELECT distinct mapguide_persons(pl.location_code) "FULL_NAME_COSTCENTER",mapguide_jobemp(pl.location_code) "TRUNCNAME_JOB",mapguide_empnum(pl.location_code) "FULLNAME_EMPNUMBER_PHONE",mapguide_english(pl.location_code)
[code]....
we have a materialized view (in Oracle 11g), usually this MV we easily drop and recreate it.
But last few days, i am trying to drop a MV, but running a long time but no result and it keeps running. not dropped also.
Bcos, db performance is good since we tried to a view using script, it is fine. Problem seems only with Materialized view.
where and how to check what is the issue?
some of MVs become invalid (yes, we did app upgrade over the weekend). I looked on every object reference in the MV, all permissions - can't find anything.I dropped MVs and created them no errors. Status changed to VALID. I decided to re-COMPILE them (because I saw public synonyms for MVs as INVALID). After compilation status changed back to INVALID.Oracle 11.2, Solaris 10.
View 2 Replies View RelatedI have got a materialized view which is created over a dblink as below:
CREATE MATERIALIZED VIEW CRIMEREPORTODSV
TABLESPACE ODS_DATA
BUILD IMMEDIATE REFRESH FAST AS
(SELECT * FROM CRIME_INT@CRISP);
This is all fine and works apart from any changes to the source table (CRIME_INT) isn't reflected unless I perform a refresh. Whereas I want any changes to be reflected straight away. I have had to use a Materialized view in this case as one of the columns in the source table is a CLOB and Oracle won't allow creation of a view with a CLOB field over DBLINK.
I created a materialized view which takes around 6 hrs to refresh. way to reduce the refresh time.The query is:
create materialized view ERC_DAILY_DISBURSMENT_MIS_VIEW
refresh complete on demand as
with disb_qur as (select e.account_no,
e.journal_dt,
e.instr_amt disbursed_amt,
[code]....
Pipe Function and Materialized View.
There is a materialized view:
CODECREATE MATERIALIZED VIEW MY_MAT_VIEW NOLOGGING
REFRESH FORCE
START WITH SYSDATE NEXT SYSDATE + 5/24/60
AS
SELECT F1,
F2,
F3
from SOMETAB;
And there is a pipelined function:
CODEDROP TYPE MY_MAT_VIEW_table_type;
DROP TYPE MY_MAT_VIEW_row_type;
CREATE TYPE MY_MAT_VIEW_row_type AS OBJECT
(
F1 number,
F2 varchar2(100),
F3 date
[code].......
I've noticed that when materialized view is near to be refreshed (every 5 minutes) there is some "delay" in getting result sets using this query:
SELECT *
FROM TABLE(FN_GET_MY_MAT_VIEW(100)) a;
And when the refresh is finished the result set returns immediately.
Question.
Is there a way to avoid such "delay" while materialized view is refreshing?
I try to do this:
CREATE MATERIALIZED VIEW MV_NESTED_DATA
NOCACHE
LOGGING
NOCOMPRESS
NOPARALLEL
BUILD IMMEDIATE
USING NO INDEX
REFRESH COMPLETE
ON DEMAND
START WITH ROUND(SYSDATE)
NEXT ROUND(SYSDATE) + 1
WITH ROWID
AS
select NESTED_TABLE_FIELD from MY_TABLE@Y_DB_LINK;
where NESTED_TABLE_FIELD is a nested table stored as T_NESTED_TABLE
And I get the error: ORA-12014: table 'T_NESTED_TABLE' does not contain a primary key constraint
Why should it if I try to create a MV with "WITH ROWID" refresh option and not "WITH PRIMARY KEY" one?
I am new to Oracle and I inherited an existing database. I have a materialized view on a table that uses a materialized view log. I have been asked to see if it is possible to categories the rows by change type (inserted, updated or deleted) and populate another materialized view or table accordingly. If this is possible then how can it be achieved.
View 1 Replies View RelatedI have a PL/SQL procedure which gathers data from multiple places as well as calculates some data. I want to store all this in a materialized view.
So, I created an object type (I've shortened the definitions):
CREATE OR REPLACE TYPE mf_record_type AS OBJECT
(identifier VARCHAR2(6),
name VARCHAR2(100));
Then created the table type of the object:
CREATE OR REPLACE TYPE mf_table_type IS TABLE OF mf_record_type;
Then in the stored procedure defined a variable of the table type:
v_mf_record mf_table_type := mf_table_type();
Then I loop and populate the record type:
v_mf_record.EXTEND(1);
v_mf_record(x) := mf_record_type(v_rec.identifier, v_mf_detail.name);
When all that is done I try and create the materialized view:
EXECUTE IMMEDIATE ('CREATE MATERIALIZED VIEW mf_snapshot_mv AS
SELECT * FROM TABLE (CAST (v_mf_record AS mf_table_type))');
ORA-00904: "V_MF_RECORD": invalid identifier
Am I doing something wrong here? Can't I create the materialized view based on something other than a physical table?
i have created a fast refresh materialized view but it is not performing fast refresh or even complete refresh.Then i have checked my materialized view capabilities then in mv_capabilities_table i got a message that materialized view log is newer than old .
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