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ADO.NET passing SQL InputOutput parameter problem

Hi.

I have problem with ParameterDirection.InputOutput.

I'm still in problem when passing imput value to InputOutput parameter. When i look on SQL I see that there is alway NULL pased regardles to what I set to Value.

Code:
SqlC_GetActualVersion.Parameters("@version").Value = CDec(Version)
SqlC_GetActualVersion.Parameters("@version").Direction = ParameterDirection.InputOutput
SqlC_GetActualVersion.Connection.Open()
SqlC_GetActualVersion.ExecuteReader()
SqlC_GetActualVersion.Connection.Close()
Version = CType(SqlC_GetActualVersion.Parameters("@version").Value, String)

SQL command send in background:
declare @P1 numeric(8,4)
SET @P1=NULL
EXEC dbo.GetActualVersion @version=@P1 output

Return value is Ok.

EBatista

you cannot access the reader value if you close the connection, and if you actually dont need the db cursor then use ExecuteNonQuery method instead:

SqlC_GetActualVersion.Connection.Open()
SqlC_GetActualVersion.ExecuteNonQuery()
SqlC_GetActualVersion.Connection.Close()
Version = CType(SqlC_GetActualVersion.Parameters("@version").Value, String)

regards

EBatista

also ExecuteReader() method is for retrieve "records" from the database, it wont perform any insert or update, so if you are trying to write back changes or inserting rows to the db you have to use ExecuteNonQuery.

patrikt

ASKER

Yes I know that. ExecuteReader is only "fosil" after my experimenting.

I'have found "way arround". Everything is working if ALL parameters are defined as InpurOutput and output in Sp. But why to do this? It looks like bug in SqlCommand.

Patrik

EBatista

nope, no bugs, can u paste the whole code for the stored procedure

ihenry

>> you cannot access the reader value if you close the connection
In addition to EBatista comment,
you can't as well retrieve the output parameters until close the datareader

Try this,
SqlC_GetActualVersion.Connection.Open()
SqlDataReader dr = SqlC_GetActualVersion.ExecuteReader()
dr.Close()
Version = CType(SqlC_GetActualVersion.Parameters("@version").Value, String)
SqlC_GetActualVersion.Connection.Close()

patrikt

ASKER

There is no problem with reading parameters. There is problem with passing paramaters.
I investigatet this and there is my result:
1) Problem is only with SQLCommand. OLEDBCommand works well.
2) Problem is only when stored procedure has some but not all paramaters as output.
3) If 1 and 2 is true and I assign value to output parameter it is set to null when calling stored procedure regardles I set it as InputOutput.

Workaround is to set all parametere in stored procedure as output. Then it works OK. But it is still bug.

Any comments?

ASKER CERTIFIED SOLUTION

ajitanand

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patrikt

ASKER

This question is not answered. I went arround the problem and have no time to investigate the source of errors.

Please give some points to Experts participating, but don't PAQ this question.

Patrik