Hello,
I am trying to use the find method to locate a particular record in a
table. The code is :
object[]findTheseVals = new object[2];
findTheseVals[0] = station_ID; // an integer
findTheseVals[1] = dt; // a datetime
DataRow foundRow = dsStationDays.T ables["StationDay s"].Rows.Find(
findTheseVals);
It is virtually verbatim from the help file. The StationDays table has a
primary key on an integer and datetime field combination, but I get a
[MissingPrimaryK eyException: Table doesn't have a primary key.] exception
when I execute the code. I have included the sql below that creates the
table:
CREATE TABLE [dbo].[StationDays] (
[Station_ID] [int] NOT NULL ,
[Day] [smalldatetime] NOT NULL ,
[Range] [float] NULL ,
[HighTide] [float] NULL ,
[LowTide] [float] NULL ,
[HighTime] [smalldatetime] NULL ,
... many more ...
[MoonSet] [smalldatetime] NULL ,
[MoonPhase] [float] NULL
) ON [PRIMARY] TEXTIMAGE_ON [PRIMARY]
GO
ALTER TABLE [dbo].[StationDays] WITH NOCHECK ADD
CONSTRAINT [PK_StationDays] PRIMARY KEY CLUSTERED
(
[Station_ID],
[Day]
) ON [PRIMARY]
GO
CREATE UNIQUE INDEX [StationDay] ON [dbo].[StationDays]([Station_ID],
[Day]) ON [PRIMARY]
GO
I'm not clear if I have an sql problem, or a csharp problem, but
hopefully someone here can help me.
Thanks
Marc Pelletier 4 5598
You must register those primary eys with your DataTable.
for example:
myDataTable.Pri maryKey = new DataColumn[] {
myDataTable.Col umns["Station_ID "], myDataTable.Col umns["Day"] };
"=?Utf-8?B?TXJOb2JvZHk =?=" <Mr******@discu ssions.microsof t.com> wrote in
news:A2******** *************** ***********@mic rosoft.com: myDataTable.Pri maryKey = new DataColumn[] { myDataTable.Col umns["Station_ID "], myDataTable.Col umns["Day"] };
That works. Thank you very much.
Marc Pelletier
PS are you related to the Mr Nobody who spills all the milk and dumps the
Lego on the floor at my house?
"Cor Ligthert" <no************ @planet.nl> wrote in
news:Oz******** ******@TK2MSFTN GP11.phx.gbl: Did you ever look at the Dataview.find method, you see it seldom in these newsgroups, however it is in my opinion very fine to use.
http://msdn.microsoft.com/library/de...y/en-us/cpref/ html/frlrfsystemdata dataviewclassfi ndtopic.asp
Thanks for reminding me about the DataView, I found it too painful to use
earlier, but I should revisit the topic.
cheers
Marc Pelletier This thread has been closed and replies have been disabled. Please start a new discussion. Similar topics |
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