delete multiple rows from table doesnt contain primary key

[=?Utf-8?B?S2F5xLFoYW4=?=]

In my project,i added datagridview to my form , i transfered my table to
datagridview and added multiple rows and when i called dataadapther.up date
,,result is ok. But when i tried it for the delete operations,i got the
error like "set primary key in your table" ,,i want delete multiple rows from
Datatable which doesnt contain primary key

[Peter Bromberg [C# MVP]]

Re: delete multiple rows from table doesnt contain primary key

If your table doesn't have a primary key, then you'll need to supply a WHERE
clause that is distinct enough to disambiguate which rows to delete.
Peter

"Kayıhan" <Kayhan@discuss ions.microsoft. comwrote in message
news:A0103CCC-9627-4DD1-A874-D132D3F8E947@mi crosoft.com...

In my project,i added datagridview to my form , i transfered my table to
datagridview and added multiple rows and when i called
dataadapther.up date
,,result is ok. But when i tried it for the delete operations,i got the
error like "set primary key in your table" ,,i want delete multiple rows
from
Datatable which doesnt contain primary key

[=?Utf-8?B?S2F5xLFoYW4=?=]

Re: delete multiple rows from table doesnt contain primary key

instead of supply where clause, i prefer choose row from table and delete it
with
"row.Delete (); dataAdapther.Up date(table);" . idont understand why i am not
allowed; what is the harm about it? why primary key is needed for delete but
not for insert or update operations?
thanks

"Peter Bromberg [C# MVP]" wrote:

If your table doesn't have a primary key, then you'll need to supply a WHERE
clause that is distinct enough to disambiguate which rows to delete.
Peter
>
"Kayıhan" <Kayhan@discuss ions.microsoft. comwrote in message
news:A0103CCC-9627-4DD1-A874-D132D3F8E947@mi crosoft.com...

In my project,i added datagridview to my form , i transfered my table to
datagridview and added multiple rows and when i called
dataadapther.up date
,,result is ok. But when i tried it for the delete operations,i got the
error like "set primary key in your table" ,,i want delete multiple rows
from
Datatable which doesnt contain primary key

>

[=?UTF-8?B?TGFzc2UgVsOlZ3PDpnRoZXIgS2FybHNlbg==?=]

Re: delete multiple rows from table doesnt contain primary key

Kayıhan wrote:

instead of supply where clause, i prefer choose row from table and delete it
with
"row.Delete (); dataAdapther.Up date(table);" . idont understand why i am not
allowed; what is the harm about it? why primary key is needed for delete but
not for insert or update operations?
thanks
>
"Peter Bromberg [C# MVP]" wrote:
>

>If your table doesn't have a primary key, then you'll need to supply a WHERE
>clause that is distinct enough to disambiguate which rows to delete.
>Peter
>>
>"Kayıhan" <Kayhan@discuss ions.microsoft. comwrote in message
>news:A0103CC C-9627-4DD1-A874-D132D3F8E947@mi crosoft.com...

>>In my project,i added datagridview to my form , i transfered my table to
>>datagridvie w and added multiple rows and when i called
>>dataadapther. update
>>,,result is ok. But when i tried it for the delete operations,i got the
>>error like "set primary key in your table" ,,i want delete multiple rows
>>from
>>Datatable which doesnt contain primary key

What if you have multiple rows with the same data? I know you can simply
say "I know I don't", but .NET can't *know* that, and it requires
something to uniquely identify the rows to delete.

On a different note, every table should have a primary key or you'll
most likely have problems with it later on, like duplicate data.

--
Lasse Vågsæther Karlsen
mailto:lasse@vk arlsen.no

http://presentationmode.blogspot.com/

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