w3hello.com logo
Home PHP C# C++ Android Java Javascript Python IOS SQL HTML videos Categories

"too many declarations of 'SUBSTR' match this call" while refreshing Materialized view


If Oracle doesn't let you run so many times "substr" function in that mv - do some trick to cheat him ;) You can make this "substr" calls before fast refresh by using virtual column like that:

alter table YOUR_TABLE add
History_substr as (DBMS_LOB.SUBSTR (History,2000,
1)) virtual;

do here other "3 more blob columns with similar conversions" as above and then you can use your virtual columns:

CREATE MATERIALIZED VIEW Employee_MV
REFRESH FAST ON COMMIT
WITH PRIMARY KEY
AS
SELECT UTL_RAW.CAST_TO_VARCHAR2(History_substr),
//BLOB column
       <3 more blob columns with similar
conversions>,
       <misc columns from different tables>,
       <rowid columns for tables for REFRESH
FAST to work>
FROM   <list of tables with JOINs>

Categories : Oracle

Related to : "too many declarations of 'SUBSTR' match this call" while refreshing Materialized view
Materialized view not refreshing
You should check the following points: You specified refresh period as 1 minutes(1/1440 day = 1 min). Is the materialized view refreshed after 1 minute? Try to execute the select part and it is finished running in 1 minute.

Categories : Oracle
Refreshing an existing materialized View
For periodic refresh you must use NEXT clause. To refresh everyday at 00:00: ALTER MATERIALIZED VIEW EMPLOYEE_INFO REFRESH COMPLETE NEXT TRUNC(SYSDATE) + 1 To refresh every 6 hours: ALTER MATERIALIZED VIEW EMPLOYEE_INFO REFRESH COMPLETE NEXT SYSDATE + 6/24 From documentation (ALTER MATERIALIZED VIEW): START WITH Clause Specify START WITH date to indicate a date for the first aut

Categories : Oracle
How can I prevent materialized views from refreshing during pg_restore?
David G Johnston posted an answer for me on the pgsql-hackers mailing list. "Have/can you try the '-l (el) & -L' options to pg_restore? http://www.postgresql.org/docs/9.3/static/app-pgrestore.html (example of usage is toward the bottom of the page) Basically re-order the command sequence so that the materialize runs as late as possible, or just disable it altogether. pg_dump/pg_restore sh

Categories : Postgresql
Refreshing a materialized view does not include added column
SELECT * is expanded at execution time, just like with all similar operations (CREATE VIEW, CREATE TABLE AS) The key word is "early binding" as opposed to "late binding". Postgres saves the list of columns present at execution time of SELECT *, columns added later are not included automatically. The query string itself is not saved, only the internal representation after expanding SELECT * and ot

Categories : Postgresql
When refreshing a materialized view, are indexes also refreshed automatically?
The indexes will of course be kept up-to-date. A quick test seems to indicate they maintain their size after each REFRESH too, which suggests they are being recreated from scratch. That would make sense because I think the view is created anew for each refresh and basically renamed into place.

Categories : Postgresql


© Copyright 2017 w3hello.com Publishing Limited. All rights reserved.