视图是一种虚拟表 ,本身是不具有数据 的,占用很少的内存空间,它是 SQL 中的一个重要概念.视图建立在已有表的基础上, 视图赖以建立的这些表称为基表.视图的创建和删除只影响视图本身,不影响对应的基表。但是当对视图中的数据进行增加、删除和修改操作时,数据表中的数据会相应地发生变化,反之亦然。视图...
现在A、B发生了转账行为(假设都有10w元,小明给小红转账10w元)--从A账户减去5w元UPDATEaccountSETmoney=money-50000WHEREname="A";--小红对应的账户增加100元UPDATEaccountSETmoney=money+50000WHEREname="B";--说明: 上面的2条SQL可以被认为是一个事务 其中有任何一条SQL语句执行错误或系统宕机都会导致数据恢复到...
When true, the layer is visible in the view. Value of this property is inherited from the layer.visible unless the developer overrides it. The layerView.visible will take precedence over layer.visible if both properties are set. Default Value:true visibleAtCurrentScale Inherited Property visib...
OleDbConnection conn =newOleDbConnection(connString);stringsql ="INSERT INTO TableName (Column1, Column2, Column3) VALUES (@Value1, @Value2, @Value3)"; conn.Open(); OleDbCommand cmd =newOleDbCommand(sql, conn);foreach(DataGridViewRow rowindataGridView1.Rows) { cmd.Parameters.AddWithValue("@...
This name is visible to users in the View list. DisplayName Name IsValidForForm False IsValidForRead True LogicalName name RequiredLevel SystemRequired Type String Format Text FormatName Text ImeMode Auto IsLocalizable True MaxLength 200 OfflineSqlQuery 展開資料表 PropertyValue Description String...
IN { # 根DNS、B网主机对非sunlinux.com请求则找根 type hint; file "named.ca"; }; zone "sunlinux.com" IN { type master; file "sunlinux.com.Bzone"; # B网主机对非sunlinux.com请求规则 }; }; view anyother { match-clients { Other; }; # 非限定网段主机 zone "." IN { type hint...
Oracle9i SQL Referencefor more information about subqueries Object Materialized Views If a materialized view is based on an object table and is created using theOFtypeclause, then the materialized view is called anobject materialized view. An object materialized view is structured in the same way as...
As Per above Example as 'Odit' category is newly added so it Should come in the last.(Not in starting or in middle) Any help .how could I make a view Auto Increment with Out changing the categoryID of Existing Category All replies (2)...
A helper component is written by a developer working in the presentation tier, while the delegate is typically written by a developer working on the services in the business tier. (Note: The delegate may also be provided as part of a framework.) Thus, this strategy is as much about who ...
In tabular models deployed to SQL Server 2012 Analysis Services (SSAS) instances. Inmultidimensional models on an SSAS server(if you’re usingPower View in SharePoint Server). Top of Page Create charts and other visualizations In Power View, you can quickly create a variety of...