Updating a view mssql
CREATE VIEW my_view AS SELECT In order to create the equivalent to a materialized view you create a table with the same name instead of a view.
CREATE TEMPORARY TABLE tmp_my_view SELECT LOCK TABLE my_database.my_view WRITE; DELETE FROM my_database.my_view; INSERT INTO my_database.my_view SELECT * FROM tmp_my_view; UNLOCK TABLES; The previous My SQL script can be run in Unix/Linux system by adding the following command as a cron entry:mysql -u userid --password=XXXXX -D my_database I was able to simulate a materialized view off of a regular view by executing a simpler script than above.
For example: CREATE TABLE new_materialized_view SELECT * from regular_view; RENAME TABLE materialized_view = old_materialized_view, new_materialized_view = materialized_view; DROP TABLE IF EXISTS old_materialized_view; Creating a materialized view emulation as described above looks good, the only problem is that we are inheriting the lack of indexes My SQL views expose.
My solution is to create a correctly indexed table according to my needs, having the exact same structure as the view, and then running something like this: LOCK TABLES materialized View WRITE; TRUNCATE materialized View; INSERT INTO materialized View SELECT * FROM regular View; UNLOCK TABLES; That way all indexes from materialized View are preserved on every "refresh".
With any regular view, "my Regular View": DROP TABLE IF EXISTS `my Database`.`my Materialized View`; CREATE TABLE `my Database`.`my Materialized View` SELECT * from `my Database`.`my Regular View`; Running this script at whatever interval is appropriate will create a new regular table with the contents of the view at the time of execution.
If an update on a row would result in a violation of a primary key or unique index, the update on that row is not performed.
CREATE TRIGGER TRGI_VW_PAYMENT ON VW_LAST_PAYMENT_DETAILS INSTEAD OF INSERT AS BEGIN INSERT INTO STUDENT_PAYMENT SELECT STD_ID, PAY_AMT, PAY_DATE FROM INSERTED END This Code working fine.
But Instead of static field i want dynamic field here, like i want to retrieve column name from information_schema.columns.
However, if such a column is updated explicitly, the only permitted value is , 2 is replaced by a constant string expression (ordering by a constant has no effect, so ordering by any constant will do).
If you experience view-evaluation errors such as just described, drop and recreate the view so that the PDF (US Ltr) - 38.0Mb PDF (A4) - 38.1Mb PDF (RPM) - 36.9Mb HTML Download (TGZ) - 10.0Mb HTML Download (Zip) - 10.1Mb HTML Download (RPM) - 8.8Mb Man Pages (TGZ) - 206.8Kb Man Pages (Zip) - 315.3Kb Info (Gzip) - 3.5Mb Info (Zip) - 3.5Mb My SQL Backup and Recovery My SQL Globalization My SQL Information Schema My SQL Installation Guide My SQL and Linux/Unix My SQL and OS X My SQL Partitioning My SQL Performance Schema My SQL Replication Using the My SQL Yum Repository My SQL Restrictions and Limitations Security in My SQL My SQL and Solaris Building My SQL from Source Starting and Stopping My SQL My SQL Tutorial My SQL and Windows My SQL NDB Cluster 7.5 My SQL 5.7 Secure Deployment Guide A simple workaround for My SQL's limitation on local variables usage in views is to use a function, which returns variable's value:create function book_subjectreturns varchar(64) asreturn @book_subject;create view thematical_books asselect title , author from books where subject = book_subject(); I ran into the restriction where your view cannot contain a subquery in the FROM clause.
The tipical command for creating a normal view is: CREATE VIEW my_view AS SELECT In order to create the equivalent to a materialized view you create a table with the same name instead of a view.