Как использовать идентификатор области видимости в SQL-команде?
Моя концепция использования идентификатора области приведена ниже. Как правильно использовать идентификатор области видимости, который поддерживает мою концепцию?
Для отдельных данных:
Imports System.Data.SqlClient
Public Class Class1
Sub Something()
Using con As SqlConnection = New SqlConnection("ConnnectionString")
Dim tran As SqlTransaction = con.BeginTransaction("ATransaction")
Using cmd As SqlCommand = New SqlCommand("DECLARE @ScopeId bigint;INSERT INTO AuditEvents(UserId) VALUES(@UserId);SELECT @ScopeId=SCOPE_IDENTITY();")
cmd.Parameters.AddWithValue("@UserId", 1)
cmd.Transaction = tran
For rowNumber As Integer = 0 To 5 'DataGridView.Rows.Count - 1
Next
Using childCommand As SqlCommand = New SqlCommand("INSERT INTO AuditEventDetails(EventId, ResourceName, OldValue, NewValue) SELECT @EventId, @ResourceName, @OldValue, @NewValue")
childCommand.Parameters.AddWithValue("@EventId", "@ScopeId") '???????
childCommand.Parameters.AddWithValue("@ResourceName", "Something")
childCommand.Parameters.AddWithValue("@OldValue", "OldValue")
childCommand.Parameters.AddWithValue("@NewValue", "NewValue")
'............................................................................
'............................................................................
'............................................................................
'............................................................................
End Using
End Using
End Using
End Sub
End Class
Для нескольких данных:
Imports System.Data.SqlClient
Public Class Class1
Sub Something()
Using con As SqlConnection = New SqlConnection("ConnnectionString")
Dim tran As SqlTransaction = con.BeginTransaction("ATransaction")
Using cmd As SqlCommand = New SqlCommand("DECLARE @ScopeId bigint;INSERT INTO AuditEvents(UserId) VALUES(@UserId);SELECT @ScopeId=SCOPE_IDENTITY();")
cmd.Parameters.AddWithValue("@UserId", 1)
cmd.Transaction = tran
For rowNumber As Integer = 0 To 5 'DataGridView.Rows.Count - 1
Using childCommand As SqlCommand = New SqlCommand("INSERT INTO AuditEventDetails(EventId, ResourceName, OldValue, NewValue) SELECT @EventId, @ResourceName, @OldValue, @NewValue")
childCommand.Parameters.AddWithValue("@EventId", "@ScopeId") '???????
childCommand.Parameters.AddWithValue("@ResourceName", "Something")
childCommand.Parameters.AddWithValue("@OldValue", "OldValue")
childCommand.Parameters.AddWithValue("@NewValue", "NewValue")
'............................................................................
'............................................................................
'............................................................................
'............................................................................
Next
End Using
End Using
End Using
End Sub
End Class
1 ответ
Если вы используете хранимые процедуры, то я думаю, что предпочтительнее использовать выходные параметры.
Для текстовых команд SQL я склонен использовать что-то вроде:
public int InsertRecord(string ANumber, string Note)
{
string SQL_INSERT_RECORD = "INSERT INTO AnumberNotes ( ANumber, Note ) VALUES ( @ANumber, @Note ) ; SELECT CAST(scope_identity() AS int)";
int NewId = -1;
try
{
using (IDbConnection conn = DBFactory.GetConnection())
{
using (IDbCommand cmd = conn.CreateCommand())
{
cmd.CommandText = SQL_INSERT_RECORD;
cmd.Parameters.Clear();
IDbDataParameter param = cmd.CreateParameter();
param.ParameterName = "@ANumber";
param.Value = ANumber;
cmd.Parameters.Add(param);
param = cmd.CreateParameter();
param.ParameterName = "@Note";
param.Value = Note;
cmd.Parameters.Add(param);
NewId = (Int32) cmd.ExecuteScalar();
}
}
} catch( Exception ex ) {
throw new DAOException("AnumberNotesDAOBase.insertRecord: ", ex );
}
return NewId;
}