CREATEVIEW[Brazil Customers]AS SELECTCustomerName, ContactName FROMCustomers WHERECountry ='Brazil'; We can query the view above as follows: Example SELECT*FROM[Brazil Customers]; The following SQL creates a view that selects every product in the "Products" table with a price higher than the ...
Note: Not all SQL types support this. (e.g. can be done in Oracle and DBT, but not PostgreSQL.)To create a materialized view, add the MATERIALIZED keyword:CREATE MATERIALIZED VIEW myView AS [Query]; To refresh the view manually use the following command:REFRESH MATERIALIZED VIEW [view nam...
Select * from Complexview // to display view data. Inserting values in an existing view: Insert into View_Name values(48,'Ajay','India'); Updating values of an existing view: update View_Name set Name='Pankaj'where empId=10 Deleting a View: To delete a view use the drop view command...
A view could be used from inside a query, a stored procedure, or from inside another view. By adding functions, joins, etc., to a view, it allows you to present exactly the data you want to the user. The sample database Northwind has some views installed by default. The view "Curren...
【实例 1】在 tb_students_info 表上创建一个名为 view_students_info 的视图,输入的 SQL 语句和执行结果如下所示。 mysql>CREATE VIEW view_students_info-> AS SELECT *FROM tb_students_info; Query OK,0rows affected (0.00sec) mysql> SELECT *FROM view_students_info;+---+---+---+---+---...
创建一个SQLQuery对象:ISQLQuery query = session.CreateSQLQuery("your_sql_query"); 添加参数:query.SetParameter("param_name", param_value, NHibernateUtil.<data_type>);其中,param_name是参数名称,param_value是参数值,NHibernateUtil.<data_type>是参数的数据类型。 添加输出参数:query.AddScalar("out...
Query The ViewWe can query the view above as follows:Example SELECT * FROM [Brazil Customers]; Try it Yourself » CREATE OR REPLACE VIEWThe CREATE OR REPLACE VIEW command updates a view.The following SQL adds the "City" column to the "Brazil Customers" view:...
第十二章 SQL命令 CREATE QUERY 创建Query 大纲 CREATE QUERY queryname(parameter_list) [characteristics] [ LANGUAGE SQL ] BEGIN code_body ; END CREATE QUERY queryname(parameter_list) [characteristics] LANGUAGE OBJECTSCRIPT { code_body } 参数 queryname - 要在存储过程类中创建的查询的名称。queryname...
[ LANGUAGE SQL ] BEGIN code_body ; END CREATE QUERY queryname(parameter_list) [characteristics] LANGUAGE OBJECTSCRIPT { code_body } 1. 2. 3. 4. 5. 6. 7. 8. 9. 参数 queryname- 要在存储过程类中创建的查询的名称。queryname必须是有效的标识符。过程名可以是限定的(schema.procname),也可以...
在 table_or_view_name 后的括号中,按排序优先级列出组合索引中要包括的列。 一个组合索引键中最多可组合 32 列。 组合索引键中的所有列必须在同一个表或视图中。 对于聚集索引,组合索引值允许的最大大小为 900 字节,对于非聚集索引则为 1,700 字节。 对于 SQL 数据库 和 SQL Server 2016 (13.x) ...