SQL VIEW

SQL VIEW is essentially a virtualized table that does not exist in nature. This table is created by an SQL statement that combines one or more tables.

Create SQL VIEW

Syntax for CREATE VIEW in SQL:

CREATE VIEW view_name_id AS
SELECT columns_id
FROM tabs
[WHERE conds]

where:

• view_name_id – The SQL VIEW name that you want to create
• WHERE conds – Optional. Conditions that must be met to include records in the view.

Example:
Here is an example of how to use SQL CREATE VIEW.

CREATE VIEW sup_orders_id AS
SELECT.suppl_id,
The orders.quantity_id,
orders.price_id
FROM suppls
INNER JOIN orders_id
ON.suppl_id = orders.suppl_id
WHERE suppls.suppl_name = 'IBM';

This SQL example CREATE VIEW will create a virtual table based on the resulting set of the select operator. Now you can query SQL VIEW as follows.

SELECT *
FROM sup_orders_id;

Update SQL VIEW

You can change the SQL VIEW definition without removing it with the CREATE OR REPLACE VIEW SQL statement.

Syntax for CREATE OR REPLACE VIEW SQL statement.

CREATE OR REPLACE VIEW view_name_id AS
SELECT columns_id
FROM tab
[WHERE conds]

Example:
Here is an example of how you would use the CREATE OR REPLACE VIEW SQL statement.

CREATE or REPLACE VIEW sup_orders_id AS
SELECT.suppl_id,
The orders.quantity_id,
orders.price_id
FROM suppls
INNER JOIN orders_id
ON.suppl_id = orders.suppl_id
WHERE suppls.suppl_name = 'Microsoft';

In this SQL example, CREATE OR REPLACE VIEW updates the SQL VIEW definition called sup_orders without removing it. If SQL VIEW does not already exist, SQL VIEW will simply be created for the first time.

Drop SQL VIEW

After creating SQL VIEW, it can be deleted using the DROP VIEW SQL statement.

Syntax for DROP VIEW SQL statement:

DROP VIEW view_name_id;

• view_name_id – Name of the view that you want to delete.

Example:
Here is an example of using SQL DROP VIEW.

DROP VIEW sup_orders_id;

In this SQL example, the DROP VIEW will delete VIEW with the name sup_orders_id.

Frequently Asked Questions

Q: Is it possible to update data in SQL VIEW.
A: VIEW in SQL is created by combining one or more tables. When you update records in a view, the records in the base tables that make up the SQL view are updated.

So, yes, you can update data in SQL VIEW if you have the appropriate privileges for the base SQL tables.

Q: Is there an SQL view if the table is removed from the database.
A: Yes, in Oracle SQL VIEW continues to exist even after one of the tables (on which SQL VIEW is based) is removed from the database. However, if you try to execute an SQL VIEW query after a table has been deleted, you will get a message that there are errors in SQL VIEW.

If you recreate a table (a table that you have deleted), SQL VIEW will be fine again.

SQL Tutorial – SQL VIEWS: Complex Queries, Cross Joins, Unions