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Is it possible to create a view on non-existent table?
It is possible to delete a dependant view after the view is installed, so it is possible for the database to be in a state where a view exists that depends on a non-existent object.
Can we create a view based on other views?
2 Answers. You can certainly have a view that’s built on top of another view: create table my_table (id number, name varchar2(20), address varchar2(30)); table MY_TABLE created.
Can you have a trigger on a view?
Yes, you can create triggers on views. (Since at least SQL Server 2000.) If you create a trigger on a view, it won’t fire on inserts to the base table. If you want something to happen when you insert data into a base table, create a trigger on the base table.
Can we call view inside view in SQL?
No, it’s fine. In many cases I personally consider it preferable to writing one view with a giant and difficult to understand definition. In my opinion, using multiple views allows you to: Encapsulate discrete logic in individual views.
How do you make a read-only view?
A view is read-only if it is not deletable, updatable, or insertable. A view can be read-only if it is a view that does not comply with at least one of the rules for deletable views. The READONLY column in the SYSCAT. VIEWS catalog view indicates a view is read-only (R).
Which conditions will create read-only views?
Read-Only Views A view will be read-only if its SELECT statement has any of the following characteristics: Specifies a row quantifier other than ALL (i.e., DISTINCT, FIRST, SKIP) Contains fields defined by subqueries or other expressions. Contains fields defined by aggregating functions and/or a GROUP BY clause.
Which statement can a trigger not be based on?
Since triggers execute as part of a transaction, the following statements are not allowed in a trigger: All create commands, including create database, create table, create index, create procedure, create default, create rule, create trigger, and create view. All drop commands. alter table and alter database.
How do you create a new view in Object Explorer?
In Object Explorer, expand the database where you want to create your new view. Right-click the Views folder, then click New View…. In the Add Table dialog box, select the element or elements that you want to include in your new view from one of the following tabs: Tables, Views, Functions, and Synonyms. Click Add, then click Close.
What happens if I create a view that depends on another view?
If I create a view that depends on a view not yet created, I get an Invalid Object error. Rather than go through the whole lot and work out the dependencies and then deal with creating them all in the correct order, is there a way I can just switch this checking off until all the views are created?
How to create a new view in Excel?
Right-click the Views folder, then click New View…. In the Add Table dialog box, select the element or elements that you want to include in your new view from one of the following tabs: Tables, Views, Functions, and Synonyms.
How to create a new view in SQL Server?
In Object Explorer, expand the database where you want to create your new view. Right-click the Views folder, then click New View…. In the Add Table dialog box, select the element or elements that you want to include in your new view from one of the following tabs: Tables, Views, Functions, and Synonyms.