How to log OPC Data Access item changes into an...
QuickOPC.NET
Product Version 5.1
Application Note
How to log OPC Data Access item changes into an SQL database
It is often required that a status of certain process variable is logged into a SQL database. Following example shows how to do that with QuickOPC:
// SimpleLogToSql: Logs OPC Data Access item changes into an SQL database, using a subscription.
// The database creation script is in the QuickOPCExamples.sql file. The examples that the database is already created.
using System;
using System.Data;
using System.Data.SqlClient;
using OpcLabs.EasyOpc.DataAccess;
namespace SimpleLogToSql
{
class Program
{
static void Main()
{
const string connectionString =
"Data Source=(local);Initial Catalog=QuickOPCExamples;Integrated Security=true";
Console.WriteLine("Starting up...");
using (var connection = new SqlConnection(connectionString))
{
connection.Open();
// Create all necessary ADO.NET objects.
var adapter = new SqlDataAdapter("SELECT * FROM SimpleLog", connection);
var dataSet = new DataSet();
adapter.FillSchema(dataSet, SchemaType.Source, "SimpleLog");
adapter.InsertCommand = new SqlCommandBuilder(adapter).GetInsertCommand();
DataTable table = dataSet.Tables["SimpleLog"];
CODE Consulting and Development, s.r.o. , Bolevecka naves 27, 323 00 Plzen, Czech Republic
e-mail: sales09@opclabs.com, Web: www.opclabs.com, tel. +420 603 214 412, fax +420 378 600 795
QuickOPC.NET-7-How to log OPC Data Access item changes into an SQL database.docx; 2013-11-21
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QuickOPC.NET
Product Version 5.1
Application Note
Console.WriteLine("Logging for 30 seconds...");
// Subscribe to an OPC item, using an anonymous method to process the notifications.
int handle = EasyDAClient.DefaultInstance.SubscribeItem(
"",
"OPCLabs.KitServer.2",
"Simulation.Incrementing (1 s)",
100,
(_, eventArgs) =>
{
Console.Write(".");
// In this example, we only log valid data. Production logger would also log errors.
if (eventArgs.Vtq != null)
{
// Fill a DataRow with the OPC data, and add it to a DataTable.
table.Rows.Clear();
DataRow row = table.NewRow();
row["ItemID"] = eventArgs.ItemDescriptor.ItemId;
row["Value"] = eventArgs.Vtq.Value;
row["Timestamp"] = eventArgs.Vtq.Timestamp;
row["Quality"] = (short)eventArgs.Vtq.Quality;
table.Rows.Add(row);
// Update the underlying DataSet using an insert command.
adapter.Update(dataSet, "SimpleLog");
}
}
);
System.Threading.Thread.Sleep(30*1000);
Console.WriteLine();
Console.WriteLine("Shutting down...");
EasyDAClient.DefaultInstance.UnsubscribeItem(handle);
}
Console.WriteLine("Finished.");
CODE Consulting and Development, s.r.o. , Bolevecka naves 27, 323 00 Plzen, Czech Republic
e-mail: sales09@opclabs.com, Web: www.opclabs.com, tel. +420 603 214 412, fax +420 378 600 795
QuickOPC.NET-7-How to log OPC Data Access item changes into an SQL database.docx; 2013-11-21
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QuickOPC.NET
Product Version 5.1
Application Note
}
}
}
The database creation script is here:
-- Creates a database with tables needed to run QuickOPC examples.
CREATE DATABASE QuickOPCExamples;
GO
USE QuickOPCExamples;
GO
CREATE TABLE SimpleLog(
ItemID nvarchar(50) NULL,
Value sql_variant NULL,
[Timestamp] datetime NULL,
Quality int NULL
);
GO
CODE Consulting and Development, s.r.o. , Bolevecka naves 27, 323 00 Plzen, Czech Republic
e-mail: sales09@opclabs.com, Web: www.opclabs.com, tel. +420 603 214 412, fax +420 378 600 795
QuickOPC.NET-7-How to log OPC Data Access item changes into an SQL database.docx; 2013-11-21
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QuickOPC.NET
Product Version 5.1
Application Note
And (part of) the resulting data may look like this:
This example will be included with the product starting with build 5.12.1305.1. Please use the example from the product itself for the most up-to-date code of the example.
General information about integration of QuickOPC and Microsoft SQL Server is here.
CODE Consulting and Development, s.r.o. , Bolevecka naves 27, 323 00 Plzen, Czech Republic
e-mail: sales09@opclabs.com, Web: www.opclabs.com, tel. +420 603 214 412, fax +420 378 600 795
QuickOPC.NET-7-How to log OPC Data Access item changes into an SQL database.docx; 2013-11-21
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QuickOPC.NET
Product Version 5.1
Application Note
OPC Alarms and Events notifications can be logged using the same approach, with EasyAEClient component.
Update: The original example (SimpleLogToSql) stores values of all data types in a single SQL_VARIANT column. As of build 5.12.1309.1, we are including two additional
examples of SQL logging with the product:
LogAsString: Values of all data types are stored in a single NVARCHAR column.
LogAsUnion: Values of all data types are stored in separate columns.
CODE Consulting and Development, s.r.o. , Bolevecka naves 27, 323 00 Plzen, Czech Republic
e-mail: sales09@opclabs.com, Web: www.opclabs.com, tel. +420 603 214 412, fax +420 378 600 795
QuickOPC.NET-7-How to log OPC Data Access item changes into an SQL database.docx; 2013-11-21
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