Then create the view as following: CREATE OR REPLACE VIEW myview (place, name, hour, price, counter) AS SELECT place, name, hour, price, func_inc_var_session() FROM yourtable WHERE input_conditions_here; The trick here is that you may see NULL on the counter column.

Jun 3, 2016 · A view definition is subject to the following restrictions: The SELECT statement cannot contain a subquery in the FROM clause. The SELECT statement cannot refer to system variables or user-defined variables .

Dec 19, 2012 · I've getting suggestions from people that using views in MySql is not a good idea. Because you can't create index for views in mysql like in oracle. But in some test that I took, indexes can be used in view select statement. Maybe I've created those views in a wrong way. I'll use a example to describe my problem.

create or replace view my_view_2 as select mv1.id, mv1.name, mt.address from my_view_1 mv1 join my_table mt on mt.id = mv1.id; view MY_VIEW_2 created. But you can't reference anything in the underlying tables, including any fields that are not part of the view:

Feb 26, 2010 · Cannot Create VIew on MySQL. 0. MYSQL - cant create view. 1. SHOW CREATE VIEW for all views in MySQL.

Sep 19, 2012 · So in order to ''create'' a primary compound key for a view you could concatenate the PKs from the three tables: concat_ws("+", table1.ID, table2.ID, table3.ID) as PK inside your view, which is in fact similarly to what most rdbms do when creating compound indexes or keys. This could be used to search in the view and you could even, depending ...

Dec 14, 2017 · A MySql View does not use for return a complete definition of a table it's basic use to return a part of the tables with a specification or marge data. V iews would not be of much use without it.The principle also applies if you select from a view that selects from the table if the view selects from the table in a subquery and the view is ...

Mar 28, 2013 · Write your selective columns, your join explicitly, and reanme the common column names from two tables. create view OrderItemsVW as select wp_cart66_orders.bill_first_name as Bill_First_Name, wp_cart66_orders.bill_last_name as Bill_Last_Name, wp_cart66_orders.Description as OrdersDescription, wp_cart66_order_items.Description as OrderItemsDescription from wp_cart66_orders inner join wp_cart66 ...

Jul 17, 2013 · Flexviews supports materialized views in MySQL by tracking changes to underlying tables and updating the table which functions as a materialized view. This approach means that SQL supported by the view is a bit restricted (as the change logging routines have to figure out which tables it should track for changes), but as far as I know this is ...

Aug 6, 2014 · Because a view is a derived table, the performance of the view is only as good as the query it is built on. If that query sucks, the performance issue will just snowball... That said, when querying a view - if a view column reference in the WHERE clause is not wrapped in a function (IE: WHERE v.column LIKE ..., not WHERE LOWER(t.column) LIKE ...