Override properties in derived classes - some have fixed value, some do not - C# Discussion Boards

Override properties in derived classes - some have fixed value, some do not

2-Sep-16 3:10

Did you even bother reading the answers the last time you posted about this[^]?

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amaturi1-Sep-16 22:32

amaturi

1-Sep-16 22:32

Hi everyone,

I would like your opinion on the following. I have an abstract base class with a property:

public abstract class BaseClass
{
    public abstract double SomeProperty { get; set; }
}

I have several derived classes based on it. Some of these derived classes have a fixed value for the property, and some do not. How would you implement the derived classes with the fixed value for SomeProperty? Maybe something like this:

public class DerivedClass : BaseClass
{
    private double _fixedValue;

    public override double SomeProperty
    {
        // For the sake of argument the value is always 1d
        get { return _fixedValue; }
        set { _fixedValue = 1d; } 
    }
}

The problem with the above implementation is that I can access the property from the outside and the code makes me think I can modify the value, but it will always give me the same result. This is not what I want, obviously.

Maybe I need to rethink how to set up the base class? If so, do you have any suggestions?

Re: Override properties in derived classes - some have fixed value, some do not

Pete O'Hanlon1-Sep-16 22:57

Re: Override properties in derived classes - some have fixed value, some do not

1-Sep-16 22:57

You don't actually have to implement anything inside the setter so it's perfectly possible to do this:

public class DerivedClass : BaseClass
{
  public override double SomeProperty
  {
    get { return 1d; }
    set { }
  }
}

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OriginalGriff1-Sep-16 23:13

OriginalGriff

1-Sep-16 23:13

As Pete says, you don't have to put anything in the setter.
But I must admit, I don't like that, as you can still write:

DerivedClass dc = new DerivedClass();
dc.SomeProperty = 23.0;

And it will appear to work - there is no compile or runtime error here which is potentially confusing:

public class DerivedClass2 : BaseClass
    {
    public override double SomeProperty { get; set; }
    }

Allows:

BaseClass bc = new DerivedClass();
bc.SomeProperty = 23.0;
bc = new DerivedClass2();
bc.SomeProperty = 23.0;

Which doesn't do the same thing in both cases.
You could throw an exception in the "unwanted" setter:

public class DerivedClass : BaseClass
    {
    public override double SomeProperty
        {
        get { return 1d; }
        set { throw new ApplicationException("Cannot set SomeProperty of DerivedClass - it is read only");  }
        }
    }

But that just moves the problem to runtime and I don't like that either.
It might be better to make the Setter protected:

public abstract class BaseClass
    {
    public abstract double SomeProperty { get; protected set; }
    }

Because at least then you are restricting the confusion to classes that are directly involved, instead of letting the rest of the world get confused as well.

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Re: Override properties in derived classes - some have fixed value, some do not

BillWoodruff2-Sep-16 1:49

BillWoodruff

2-Sep-16 1:49

I learn something: I happy. You good.

«There is a spectrum, from "clearly desirable behaviour," to "possibly dodgy behavior that still makes some sense," to "clearly undesirable behavior." We try to make the latter into warnings or, better, errors. But stuff that is in the middle category you don’t want to restrict unless there is a clear way to work around it.» Eric Lippert, May 14, 2008

Re: Override properties in derived classes - some have fixed value, some do not

OriginalGriff2-Sep-16 3:57

OriginalGriff

2-Sep-16 3:57

"If you learn something new every day, you can teach something new every day." --- Martha Stewart

My wife learns something new from me everyday. She thinks it's important to learn from her mistakes. Wink | ;)

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TimeStamp to PDF

Member 119141971-Sep-16 22:06

Member 11914197

1-Sep-16 22:06

Hello,
I have problem with insert timestamp to PDF.
On line Array.Copy(pk, 0, outc, 0, pk.Length); is error because outc.Length = 4096, but pk.Length = 7541. Metod DejCasoveRazitko work correctly.

P.S. Sorry, my English is bad Sigh | :sigh:

private const String ID_TIME_STAMP_TOKEN = "1.2.840.113549.1.9.16.2.14"; // RFC 3161 id-aa-timeStampToken

public void PodepisPdfCer(string SouborPDF, string OtiskCertifikatu)
{
    //http://www.dotnetportal.cz/blogy/15/Null-Reference-Exception/5250/Digitalni-podepisovani-PDF-souboru-v-C-cast-2

    //Get certificate
    //Open the currently logged-in user certificate store
    var store = new System.Security.Cryptography.X509Certificates.X509Store(System.Security.Cryptography.X509Certificates.StoreName.My, System.Security.Cryptography.X509Certificates.StoreLocation.CurrentUser);
    store.Open(System.Security.Cryptography.X509Certificates.OpenFlags.ReadOnly);

    string thumbprint = OtiskCertifikatu.Replace(" ", "").ToUpperInvariant();
    if (thumbprint[0] == 8206)
    {
        thumbprint = thumbprint.Substring(1);
    }

    //Select a certificate from the certificate store
    var certs = store.Certificates.Find(System.Security.Cryptography.X509Certificates.X509FindType.FindByThumbprint, thumbprint, true);
    store.Close();

    //Verify that a certificate exists
    if (certs.Count == 0)
    {
        MessageBox.Show("Nelze najít určený certifikát v Current user certificate store!", "Sign PDF", MessageBoxButtons.OK, MessageBoxIcon.Warning);
        return;
    }

    //Open Pdf document
    byte[] pdfData = File.ReadAllBytes(SouborPDF);

    //Sign the PDF document
    using (MemoryStream stream = new MemoryStream())
    {
        var reader = new PdfReader(pdfData);
        var stp = PdfStamper.CreateSignature(reader, stream, '\0');
        var sap = stp.SignatureAppearance;

        //Protect certain features of the document
        stp.SetEncryption(null,
            Guid.NewGuid().ToByteArray(), //random password
            PdfWriter.ALLOW_PRINTING | PdfWriter.ALLOW_COPY | PdfWriter.ALLOW_SCREENREADERS,
            PdfWriter.ENCRYPTION_AES_256);

        //Get certificate chain
        var cp = new Org.BouncyCastle.X509.X509CertificateParser();
        var certChain = new Org.BouncyCastle.X509.X509Certificate[] { cp.ReadCertificate(certs[0].RawData) };

        sap.SetCrypto(null, certChain, null, PdfSignatureAppearance.WINCER_SIGNED);

        //Set signature appearance
        BaseFont helvetica = BaseFont.CreateFont(BaseFont.HELVETICA, BaseFont.CP1250, BaseFont.EMBEDDED);
        iTextSharp.text.Font font = new iTextSharp.text.Font(helvetica, 12, iTextSharp.text.Font.NORMAL);
        sap.Layer2Font = font;
        //sap.SetVisibleSignature(new iTextSharp.text.Rectangle(415, 100, 585, 40), 1, null);

        var dic = new PdfSignature(PdfName.ADOBE_PPKMS, PdfName.ADBE_PKCS7_SHA1);
        //Set some stuff in the signature dictionary.
        dic.Date = new PdfDate(sap.SignDate);
        dic.Name = certs[0].Subject;    //Certificate name
        if (sap.Reason != null)
        {
            dic.Reason = sap.Reason;
        }
        if (sap.Location != null)
        {
            dic.Location = sap.Location;
        }

        //Set the crypto dictionary
        sap.CryptoDictionary = dic;

        //Set the size of the certificates and signature.
        int csize = 4096; //Size of the signature - 4K

        //Reserve some space for certs and signatures
        var reservedSpace = new Dictionary<PdfName, int>();
        reservedSpace[PdfName.CONTENTS] = csize * 2 + 2; //*2 because binary data is stored as hex strings. +2 for end of field
        sap.PreClose(reservedSpace);    //Actually reserve it

        //Build the signature
        System.Security.Cryptography.HashAlgorithm sha = new System.Security.Cryptography.SHA256CryptoServiceProvider();

        var sapStream = sap.GetRangeStream();
        int read = 0;
        byte[] buff = new byte[8192];
        while ((read = sapStream.Read(buff, 0, 8192)) > 0)
        {
            sha.TransformBlock(buff, 0, read, buff, 0);
        }
        sha.TransformFinalBlock(buff, 0, 0);

        //Place message in a ContentInfo object. This is required to build a SignedCms object.
        System.Security.Cryptography.Pkcs.ContentInfo contentInfo = new System.Security.Cryptography.Pkcs.ContentInfo(sha.Hash);

        //Instantiate SignedCms object with the ContentInfo above.
        //Has default SubjectIdentifierType IssuerAndSerialNumber.
        System.Security.Cryptography.Pkcs.SignedCms signedCms = new System.Security.Cryptography.Pkcs.SignedCms(contentInfo, false);

        //Formulate a CmsSigner object for the signer.
        System.Security.Cryptography.Pkcs.CmsSigner cmsSigner = new System.Security.Cryptography.Pkcs.CmsSigner(certs[0]);  //First cert in the chain is the signer cert

        //Do the whole certificate chain. This way intermediate certificates get sent across as well.
        cmsSigner.IncludeOption = System.Security.Cryptography.X509Certificates.X509IncludeOption.ExcludeRoot;

        //Časové razítko z TSA
        if (!String.IsNullOrEmpty(textBox_ServerCasovehoRazitka.Text.Trim()))
        {
            try
            {
                System.Security.Cryptography.AsnEncodedData timeData = new System.Security.Cryptography.Pkcs.Pkcs9AttributeObject(ID_TIME_STAMP_TOKEN,
                                                                                                                                  DejCasoveRazitko(stream.GetBuffer(), textBox_ServerCasovehoRazitka.Text)
                                                                                                                                 );
                cmsSigner.UnsignedAttributes.Add(timeData);
            }
            catch (Exception e)
            {
                MessageBox.Show("Chyba TSA!\n" + e.Message);
            }
        }

        //Sign the CMS/PKCS #7 message. The second argument is needed to ask for the pin.
        signedCms.ComputeSignature(cmsSigner, false);

        //Encode the CMS/PKCS #7 message.
        byte[] pk = signedCms.Encode();

        //Put the certs and signature into the reserved buffer
        byte[] outc = new byte[csize];
        Array.Copy(pk, 0, outc, 0, pk.Length);

        //Put the reserved buffer into the reserved space
        PdfDictionary certificateDictionary = new PdfDictionary();
        //certificateDictionary.Put(PdfName.CONTENTS, new PdfString(outc).SetHexWriting(true));

        //Write the signature
        sap.Close(certificateDictionary);

        //Close the stamper and save it
        stp.Close();

        reader.Close();

        byte[] signedData = stream.GetBuffer();
        File.WriteAllBytes(SouborPDF, signedData);
    }
}

static protected byte[] DejCasoveRazitko(byte[] PDF, string ServerTSA)
{
    System.Security.Cryptography.SHA256Managed hashString = new System.Security.Cryptography.SHA256Managed();
    string hex = "";

    var hashValue = hashString.ComputeHash(PDF);
    foreach (byte x in hashValue)
    {
        hex += String.Format("{0:x2}", x);
    }

    // VSTUPEM je hash dokumentu, pro který se razítko vyžaduje
    NotservisTSA.GetTimeStampRequest Request = new NotservisTSA.GetTimeStampRequest(new NotservisTSA.GetTimeStampRequestBody(hex, 0));

    NotservisTSA.Print2PDF_WebServiceSoap Soap = new NotservisTSA.Print2PDF_WebServiceSoapClient();

    ((NotservisTSA.Print2PDF_WebServiceSoapClient)Soap).Endpoint.Address = new System.ServiceModel.EndpointAddress(new Uri(ServerTSA + "/Default.asmx"));

    PodepsaniPDF.NotservisTSA.GetTimeStampResponse Response = Soap.GetTimeStamp(Request);

    // VÝSTUPEM je zakódované časové razítko (GetTimeStampResult - BASE-64 v kódované struktuře TimeStampResp, viz RFC 3161) a návratová hodnota s případným popisem chyby.
    byte[] responseBytes = Encoding.ASCII.GetBytes(Response.Body.GetTimeStampResult);

    if(!String.IsNullOrEmpty(Response.Body.Error))
        MessageBox.Show(Response.Body.Error, "Chyba", MessageBoxButtons.OK, MessageBoxIcon.Error);

    string base64String = Encoding.UTF8.GetString(responseBytes, 0, responseBytes.Length);
    return Convert.FromBase64String(base64String);
}

Suggesstions on saving 100s of rowsto the database

Giridhar Aruri1-Sep-16 15:27

Giridhar Aruri

1-Sep-16 15:27

Hi Team,

Could someone suggest ideal way to submit 100s of rows from UI to db ?

i think better approach would be to Prepare XML and send it to DB.
Any other ideas are welcome.

Thanks,
Giri

Re: Suggesstions on saving 100s of rowsto the database

OriginalGriff1-Sep-16 20:22

OriginalGriff

1-Sep-16 20:22

Or you could just use the SqlBulkCopy.WriteToServer Method[^]

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Re: Suggesstions on saving 100s of rowsto the database

Eddy Vluggen1-Sep-16 23:10

Eddy Vluggen

1-Sep-16 23:10

Depends on the database-server.

In the case of SQLite, you'd be better of doing 100 inserts wrapped in a transaction.

Bastard Programmer from Hell Suspicious | :suss:

If you can't read my code, try converting it here[^]

Need to cancel BackgroundWorker

David_411-Sep-16 13:01

1-Sep-16 13:01

Hello all. I have a background worker that executes a query against an SQL Server database. The user clicks a button and the query runs, then the results of the query go into a datagrid. The users are requesting a Cancel button for the query because the queries can take a very long time to run. So when the user clicks the Run Query button, a small form with a Cancel Button opens. If the user clicks the button, DialogueResult.Cancel is returned and I execute CancelAsync().

Meanwhile, in my DoWork thread, I am preparing to run the query. When I run the query, I execute

adapter3.Fill(GlobalData.g_queryData);

So, there is no loop. Most of the forums I have seen tell you to check Backgroundworker.CancellationPending. The problem is that I am not running in a loop.

So, can someone suggest maybe another approach to canceling a query that is currently running?

Thanks,
David

using (SqlConnection connection = new SqlConnection(GlobalStr.sqlConnStringMetadata))
                {
                    try
                    {
                        connection.Open();

                        /*
                         * DRW 3/10/2016
                         * Added the following Transaction object in order to set the isolation level of all queries
                         * run from MAnDA to to Read Uncommited.
                         */
                        SqlTransaction Transaction = connection.BeginTransaction(IsolationLevel.ReadUncommitted);

                        using (SqlCommand testQuery = new SqlCommand(GlobalStr.previewQueryString, connection))
                        {
                            /*
                             * DRW 3/11/2016
                             * User sets the query timeout value via a textbox on the main form. The value is held in a variable.
                             * testQuery.CommandTimeout = 300;
                             */

                            testQuery.CommandTimeout = m_QueryTimeout;
                            testQuery.Transaction = Transaction;                           

                            using (SqlDataAdapter adapter3 = new SqlDataAdapter(testQuery))
                            {
                                adapter3.Fill(GlobalData.g_queryData);

                                // Open the DataSetViewer form and send the table to it
                                DataSetViewer dsv = new DataSetViewer();
                                dsv.SetSource(GlobalData.g_queryData);
                                // set the dataview classification 05272015
                                string strClassification = string.Format("{0} {1}", GlobalStr.g_classification, GlobalStr.g_releaseability);
                                dsv.setClassification(strClassification);
                                Cursor.Current = Cursors.Default;
                                dsv.ShowDialog();

                                //dataGridView1.DataSource = GlobalData.g_queryData;
                            }
                        }
                        connection.Close();
                    }
                    catch (Exception ex)
                    {
                        /// Print error message
                        MessageBox.Show("The query test failed: " + ex.Message);
                        return;
                    }
                }

Pete O'Hanlon1-Sep-16 21:01

1-Sep-16 21:01

I have accomplished a similar task in the past using a variation of this code:

public sealed class ExtendedBackgroundWorker : BackgroundWorker
{
  private Thread thread;
  public void Stop()
  {
    thread?.Abort(); // Abort the thread if it has been set.
	thread = null;
  }
  protected override void OnDoWork(DoWorkEventArgs eventArgs)
  {
    thread = Thread.CurrentThread;
	try
	{
	  base.OnDoWork(eventArgs);
	}
	catch (ThreadAbortException threadAbort)
	{
	  Debug.WriteLine("ExtendedBackgroundWorker has been aborted");
	  Thread.ResetAbort();
	  eventArgs.Cancel = true;
	}
  }
}

With this, you're going to Abort the Thread. Now, an Abort is normally a bad method to call (there are various resources you can look up about why it's not recommended), but we're going to handle it in a controlled manner. When the thread is aborted, a ThreadAbortException is raised so, in our OnDoWork handler, we want to Cancel the DoWorkEventArgs and reset the Abort so that it doesn't destabilise our system. Now, you have a background worker that can be killed from the calling code. By the way, I call the method Stop rather than Abort because while this code is carefully written to prevent Abort issues, I don't want people to get into the habit of calling Abort wherever they see thread codes. By hiding the implementation, I'm hiding the idea that Abort should be called.

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David_416-Sep-16 8:12

6-Sep-16 8:12

Thank you Peter. I actually worked on this over my long weekend. Sorry for not getting back to you sooner.

I got it working by partly using your suggestion to abort the thread. This works because the only types of queries that will be run here are SELECT queries. So no records are actually being modified. So, no need to worry about rolling back transactions.

I am no longer using a background worker. I am just creating my own thread. I want to show my code below.

Class Level Code:

CloseCancelForm(); //This form contains the Cancel Button

Cancel Form

public partial class FormCancelQuery : Form
    {
        DialogResult result = DialogResult.OK;
        public FormCancelQuery()
        {
            InitializeComponent();
        }

        private void btnCancel_Click(object sender, EventArgs e)
        {
            result = DialogResult.Cancel;
            this.Close();
        }
    }

Main UI Form

private void qbTestQueryBtn_Click(object sender, EventArgs e)
        {            
            frmCancel = new FormCancelQuery();
            RunQueryThread = new Thread(new ThreadStart(RunQuery));
            RunQueryThread.Start();
            DialogResult dr = frmCancel.ShowDialog(this);
            if (dr == DialogResult.Cancel)
            {
                frmCancel.DialogResult = DialogResult.OK;
                RunQueryThread.Abort();
            }                       
        }

private void RunQuery()
        {
            if (ValidQuery())
            {
                string queryTestString = GlobalStr.previewQueryString;
                // Check the query for the where fill flag, and if it contains it, branch off to the filling routine
                string fillFlag = "'mandafillflag'";
                if (queryTestString.ToLower().Contains(fillFlag))
                {
                    MessageBox.Show("This query requires completing the fields. Click OK to begin procedure.");
                    QueryFiller qf = new QueryFiller();
                    queryTestString = qf.FillQuery(queryTestString.ToLower(), fillFlag);
                }

                GlobalStr.previewQueryString = queryTestString;
                //selectTB.Text = GlobalStr.previewQueryString;
                selectTB.Invoke(new MethodInvoker(delegate { selectTB.Text = GlobalStr.previewQueryString; }));
                //whereTB.Clear();
                whereTB.Invoke(new MethodInvoker(delegate { whereTB.Clear(); }));
                //fromTB.Clear();
                fromTB.Invoke(new MethodInvoker(delegate { fromTB.Clear(); }));
                //orderTB.Clear();
                orderTB.Invoke(new MethodInvoker(delegate { orderTB.Clear(); }));

                try
                {
                    //examineQueryInputString(GlobalStr.previewQueryString, "", cmplxWhereClauseCB.Checked);
                    examineQueryInputString(GlobalStr.previewQueryString, "", GlobalBool.g_CmplxWhereClauseChecked);
                }
                catch (System.Exception ex)
                {
                    CloseCancelForm();
                    MessageBox.Show(ex.Message);
                    return;
                }

                // Clear the data table
                
                try
                {
                    GlobalData.g_queryData.Rows.Clear();
                    GlobalData.g_queryData.Columns.Clear();
                }
                catch (Exception ex)
                {
                    GlobalData.g_queryData = new DataTable();                    
                }                
                
                // set the wait cursor if query takes long. ens 01/28/2015
                Cursor.Current = Cursors.WaitCursor;
                //using (SqlConnection connection = new SqlConnection(GlobalStr.sqlConnString))
                using (SqlConnection connection = new SqlConnection(GlobalStr.sqlConnStringMetadata))
                {
                    try
                    {
                        connection.Open();

                        /*
                         * DRW 3/10/2016
                         * Added the following Transaction object in order to set the isolation level of all queries
                         * run from MAnDA to to Read Uncommited.
                         */
                        SqlTransaction Transaction = connection.BeginTransaction(IsolationLevel.ReadUncommitted);

                        using (SqlCommand testQuery = new SqlCommand(GlobalStr.previewQueryString, connection))
                        {
                            /*
                             * DRW 3/11/2016
                             * User sets the query timeout value via a textbox on the main form. The value is held in a variable.
                             * testQuery.CommandTimeout = 300;
                             */

                            testQuery.CommandTimeout = m_QueryTimeout;
                            testQuery.Transaction = Transaction;                           

                            using (SqlDataAdapter adapter3 = new SqlDataAdapter(testQuery))
                            {
                                adapter3.Fill(GlobalData.g_queryData);

                                // Open the DataSetViewer form and send the table to it
                                DataSetViewer dsv = new DataSetViewer();
                                dsv.SetSource(GlobalData.g_queryData);
                                // set the dataview classification 05272015
                                string strClassification = string.Format("{0} {1}", GlobalStr.g_classification, GlobalStr.g_releaseability);
                                dsv.setClassification(strClassification);
                                Cursor.Current = Cursors.Default;
                                CloseCancelForm();
                                dsv.ShowDialog();

                                //dataGridView1.DataSource = GlobalData.g_queryData;
                            }
                        }
                        connection.Close();                        
                    }
                    catch (Exception ex)
                    {
                        //frmCancel.Invoke(new MethodInvoker(delegate { frmCancel.Close(); }));                        
                        if (ex.Message != "Thread was being aborted.")
                        {
                            CloseCancelForm();
                            /// Print error message
                            MessageBox.Show("The query test failed: " + ex.Message);                            
                        }
                        return;
                    }
                }
            }
            else
            {
                CloseCancelForm();
                MessageBox.Show("SQL test failed.");
            } 
        }

        private void CloseCancelForm()
        {            
            try
            {
                if (frmCancel.InvokeRequired)
                {
                    frmCancel.Invoke(new MethodInvoker(delegate { frmCancel.DialogResult = DialogResult.OK; }));
                    frmCancel.Invoke(new MethodInvoker(delegate { frmCancel.Close(); }));
                }
                else
                {
                    frmCancel.DialogResult = DialogResult.OK;
                    frmCancel.Close();
                }                
            }
            catch(Exception ex)
            {
                string message = ex.Message;
                return;
            }
        }

Hopefully this will help someone.

David

Pete O'Hanlon6-Sep-16 9:39

6-Sep-16 9:39

Thanks for coming back and posting your update. Glad you got it working.

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Gerry Schmitz3-Sep-16 6:53

Gerry Schmitz

3-Sep-16 6:53

Yes; the usual reaction is to figure out how to "cancel the query".

Perhaps one should first look at "tuning" the query.

The "query" is being confused with the "what it is that is submitting the query" (existentially speaking). The "query" is the "database server engine"; not some thread that submitted the query.

Is the query returning a scalar or a "set"?

If a set, is it required to be viewed and paged? Reported on?

Is virtualization an option for "paged" results.

Can the execution plan be estimated and presented before kicking off the query?

What is the nature of query? Would a data reader suffice? Can intermediate results be used to confirm kicking of further queries instead of resorting to a single "large" (poorly optimized) query (e.g. when "drilling" down).

etc....

David_416-Sep-16 8:20

6-Sep-16 8:20

Hi Gerry,

These are user created queries, so there is no tuning the query.

Yes, I guess you are correct. The query is being run by the database server engine, so I guess there is no canceling the query. All I can really do is force my program to stop waiting for the query results. I guess since the query is running in a transaction, I could try rolling back the transaction.

The query returns a set.

The query is created by the user through a query designer that we wrote in C#. It only allows the user to execute SELECT queries against tables or Views in the database. It returns a dataset with the results displayed in a datagrid. The results can then be exported to a CSV or XLSX file.

Thanks or your input.

Gerry Schmitz6-Sep-16 9:08

Gerry Schmitz

6-Sep-16 9:08

The queries may be "user-created", but that does not mean they should have "free access" to the database.

I would give users "unlimited" query abilities; but with some "reasonableness" applied.

With an ERP system, it makes little sense to run queries on "all".

Based on the context (User; Department; Title; etc.), users may be required to provide a "year", "month", "department code", etc. via a query interface.

For "historical" data analysis, we would build data warehouses ("facts"; dimensions; "star" relationships) that were "optimized" for ad-hoc queries.

One simply does not unleash users on "unstructured" data without some planning (and expect performance).

David_416-Sep-16 9:14

6-Sep-16 9:14

Hi Gerry. They do not have free unlimited access to everything. We use User Roles to control what they have access to. They cannot run Action Queries or DROP or CREATE queries. If the application needs to do that, then we use an Application Role with elevated permissions. We have covered our bases I think.

Thanks,

David

David_416-Sep-16 9:18