i have a web page, that will load data from three tables is there a way to load all the data at once using a Sqldatasource, or must i do it in coding?
i also want to sort it. but that i know how to do. and all the data goes into a gridview, which is why i want to use just one Sqldatasource.
this is what i have so far:
<asp:SqlDataSource ID="SqlDataSource1" runat="server" ConnectionString="<%$
ConnectionStrings:testpicsConnectionString %>" SelectCommand="SELECT * FROM [tball]
select * from tb1
select * from tb2"></asp:SqlDataSource>
and do i just add
sort id desc
to them all?
i just want to know can it be done with one Sqldatasource?
btw, I'm using c# and sql (obviously)
sorry forgot to add the schema from the tables
all the tables are the same: they have id, desc and pic
id int primary key identity not null,
[desc] varchar(max) null,
pic varbinary(max) null
that is used for all tables. so if i had to join, on where or what would i join?
you could use UNION to select the columns from the different tables...
select * from tb1
union all
select * from tb2
union all
select * from tb3
order by id desc;
union all
- will show all records in your result.
union
- will remove duplicate records from your result.
Union all
will give better performance as the database engine won't have any overhead for managing the result to remove the duplicates.
您还可以在数据库中创建一个视图,该视图将收集所需的所有数据,然后在c#应用程序中对其进行查询。
select * from Table1 union all select * from Table2 order by 1
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