sp_helpdb

 This query produces the following output:

 Hope this helps!

1.  Export the following data into a CSV file.  For this example, we’re using the AdventureWorks database.  The following SQL statement was used to get the sample data below: 

SELECT EmployeeID, LoginID, Title, MaritalStatus, VacationHours FROM HumanResources.Employee

2.  Create a Windows Console Application in C# and create the class that maps to your file like the following:

public class Employee
    {
        public int EmpID { get; set; }
        public string LoginID { get; set; }
        public string Title { get; set; }
        public string MaritalStatus { get; set; }
        public int VacationHours { get; set; }
    }

3.  Code that creates the query to get only those records where VacationHours > 0.  We will also print out every line and then the last line will print out the number of records.

var query = from e in
                           (from line in File.ReadAllLines(@"C:\AdvWorksEmployees.csv")
                            let employeeRecord = line.Split(',')
                            select new Employee()
                                {
                                    EmpID = int.Parse(employeeRecord[0]),
                                    LoginID = employeeRecord[1],
                                    Title = employeeRecord[2],
                                    MaritalStatus = employeeRecord[3],
                                    VacationHours = int.Parse(employeeRecord[4])
                                })
                       where e.VacationHours > 0
                       select e;

int rowCount = query.Distinct().Count();

foreach (var item in query)
{
     Console.WriteLine("{0}, {1}, {2}, {3}, {4}", item.EmpID, item.LoginID,   item.MaritalStatus, item.Title, item.VacationHours); 
 }

Console.WriteLine("Number of rows:  " + rowCount);

4.  We’re done!!  Here’s the entire code file for reference:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.IO;

namespace TextToLinqDemo
{
    public class Employee
    {
        public int EmpID { get; set; }
        public string LoginID { get; set; }
        public string Title { get; set; }
        public string MaritalStatus { get; set; }
        public int VacationHours { get; set; }
    }

    class Program
    {
        static void Main(string[] args)
        {
            var query = from e in
                            (from line in File.ReadAllLines(@"C:\AdvWorksEmployees.csv")
                             let employeeRecord = line.Split(',')
                             select new Employee()
                                 {
                                     EmpID = int.Parse(employeeRecord[0]),
                                     LoginID = employeeRecord[1],
                                     Title = employeeRecord[2],
                                     MaritalStatus = employeeRecord[3],
                                     VacationHours = int.Parse(employeeRecord[4])
                                 })
                        where e.VacationHours > 0
                        select e;

            int rowCount = query.Distinct().Count();

            foreach (var item in query)
            {
                Console.WriteLine("{0}, {1}, {2}, {3}, {4}", item.EmpID, item.LoginID,
                                    item.MaritalStatus, item.Title, item.VacationHours);
            }

            Console.WriteLine("Number of rows:  " + rowCount);
            Console.Read();
        }

    }
}

Why would you use this?

• Need to import a file but only import select records in the file, this would be a good tool to filter out data before importing

Other resources:  101 LINQ Samples – great site to dig deeper into LINQ

You can think of it as a Publish—>Subscription type of idea where if you subscribe to a magazine, for instance, you receive the magazine.  When your subscription runs out, the magazine is no longer delivered.

Here are the key components to an Observer Pattern:

1.  Subject – a value/object that, when changes, notifies the observers

2.  Observer – objects that have subscribed to the Provider to be notified when it’s state has changed.

Some examples on when to use this would include the following:

• Weather – the weather statistics change and there’s a need to notify multiple observers (maybe multiple user interfaces)
• Stocks – when a stock price changed, there’s a need to notify all of their investors (observers).

Here is a C# console application coding example using a Stock as a Subject and Investors as observers:

Show Code

<font size="1">using System;
using System.Collections.Generic;
using System.Text;

namespace ObserverPattern
{
    class Program
    {
        static void Main(string[] args)
        {
            // Create MSFT stock (subject) and attach investors (observers)

            MSFT msft = new MSFT(&quot;MSFT&quot;, 120.00);

            //Attach each investor to the stock
            msft.Attach(new Investor(&quot;Sorros&quot;));
            msft.Attach(new Investor(&quot;Berkshire&quot;));

            // Fluctuating prices will notify investors
            msft.Price = 120.10;
            msft.Price = 121.00;
            msft.Price = 120.50;
            msft.Price = 120.75;
            // Wait for user

            Console.ReadKey();

        }
    }

    abstract class Stock
    {
        private string _symbol;
        private double _price;
        private List<iinvestor> _investors = new List<iinvestor>();

        //Constructor
        public Stock(string symbol, double price)
        {
            this._symbol = symbol;
            this._price = price;
        }

        public void Attach(IInvestor investor)
        {
            _investors.Add(investor);
        }

        public void Detach(IInvestor investor)
        {
            _investors.Remove(investor);
        }

        public void Notify()
        {
            foreach (IInvestor investor in _investors)
            {
                investor.Update(this);
            }

            Console.WriteLine(&quot;&quot;);
        }

        public double Price
        {
            get { return _price; }
            set
            {
                if (_price != value)
                {
                    _price = value;
                    Notify();
                }
            }
        }

        //Gets the Symbol
        public string Symbol
        {
            get { return _symbol; }
        }
    }

        class MSFT : Stock
        {
            public MSFT(string symbol, double price)
                : base(symbol, price)
            { }
        }

        interface IInvestor
        {
            void Update(Stock stock);
        }

        class Investor : IInvestor
        {
            private string _name;
            private Stock _stock;

            public Investor(string name)
            {
                this._name = name;
            }

            public void Update(Stock stock)
            {
                Console.WriteLine(&quot;Notified {0} of {1}'s &quot; + &quot;change to {2:C}&quot;, _name, stock.Symbol, stock.Price);
            }

            public Stock stock
            {
                get { return _stock; }
                set { _stock = value; }
            }
        }
    }
</font>

I noticed this happened after I installed Microsoft Office Live Add-In.

Solution:  Type the url as http://[servername]/loader.aspx instead of http://[servername]

Here’s a SQL code snippet that will do exactly that:

SELECT Employee, Count(Employee) AS NumOccurrences

FROM table

GROUP BY Employee

HAVING (Count(Employee) > 1)

You can also order them by the number of duplicates you have like this:
SELECT Employee, Count(Employee) AS NumOccurrences

FROM table

GROUP BY Employee

HAVING (Count(Employee) > 1)

ORDER BY (Count(Employee)) DESC
This little trick was taken from a Microsoft entry that also explains How to Remove Duplicate Rows from a table in SQL

1.  Open Visual Studio 2005 -> New Project -> Visual C# -> Database -> SQL Server Project -> OK

2.  Add a Database Reference: Enter SQL Server name, credentials, and database name -> OK

3.  Accept the prompt to enable CLR debugging in the database.

4.  In the Solution Explorer window, right click on your Project name -> Add -> User Defined Function -> save it as “IsUserPartOfADGroup.cs” (this will be the name of your function)

5.  Copy and paste the following code into the “IsUserPartOfADGroup.cs window:

 

using System;
using System.Data;
using System.Data.SqlClient;
using System.Data.SqlTypes;
using Microsoft.SqlServer.Server;

using System.DirectoryServices;
using System.Collections;

public partial class UserDefinedFunctions
{
    [Microsoft.SqlServer.Server.SqlFunction]
    public static SqlInt16 IsUserPartOfADGroup(string username, string GroupToCheck)
    {
        string[] ary = username.ToString().Split('\');
        return Check_If_Member_Of_AD_Group(ary[1].ToString(),
                                                        GroupToCheck.Trim(),
                                                        ary[0].ToString(),
                                                        "",
                                                        "");
    }

    public static SqlInt16 Check_If_Member_Of_AD_Group(string username,
                                                            string grouptoCheck,
                                                            string domain,
                                                            string adlogin,
                                                            string adpassword)
    {

        try
        {
            //Sets up the connection string
            string entryString = "LDAP://" + domain;
            DirectoryEntry de;

            grouptoCheck = grouptoCheck.ToLower();

            if (adlogin != "" && adpassword != "")
            {
                de = new DirectoryEntry(entryString, adlogin, adpassword);
            }
            else
            {
                de = new DirectoryEntry(entryString);
            }

            DirectorySearcher myDirectorySearcher = new DirectorySearcher(de);
            myDirectorySearcher.Filter = "sAMAccountName=" + username;
            myDirectorySearcher.PropertiesToLoad.Add("MemberOf");

            SearchResult myResult = myDirectorySearcher.FindOne();

            int numberOfGroups = myResult.Properties["MemberOf"].Count - 1;
            string tmpString;

            while (numberOfGroups >= 0)
            {
                tmpString = myResult.Properties["MemberOf"][numberOfGroups].ToString();
                tmpString = tmpString.Substring(0, tmpString.IndexOf(",", 0));

                tmpString = tmpString.Replace("CN=", "");
                tmpString = tmpString.ToLower();
                tmpString = tmpString.Trim();

                if (grouptoCheck == tmpString)
                {
                    return 1; //return true
                }

                numberOfGroups = numberOfGroups - 1;
            }

            return 0; //return false
        }

        catch (Exception ex)
        {
            string parms = "UserName:  " + username + "rnGroupToCheck: " + grouptoCheck + "rnDomain:  " + domain + "rnADLogin:  " + adlogin;
            WriteError(parms, ex.Message.ToString());

            return -1; //Error
        }
    }

    public static void WriteError(string parameters, string errorMsg)
    {
        //Creates a Souce in the Application Log
        string source = "SQL UDF";

        if (!System.Diagnostics.EventLog.SourceExists(source))
        {
            System.Diagnostics.EventLog.CreateEventSource(source, "Application");
        }

        System.Diagnostics.EventLog aLog = new System.Diagnostics.EventLog();
        aLog.Source = source;
        aLog.WriteEntry("Error checking if user is a part of an AD Group:  rn Parameters:  rn" + parameters + "rnError Message:  " + errorMsg.ToString(), System.Diagnostics.EventLogEntryType.Error);
    }

};

6.  Save. In Solution Explorer , right click on the name of your project and click Properties -> Select Database from left hand side -> Choose Permission Level to “Unsafe”.

• Note:  Not choosing “Unsafe” resulted in throwing a security exception when you attempt to run the UDF from SQL.

7.  Open SQL Server Management Studio and execute the following command using the name of the database you are using from step 2.

EXEC sp_configure ‘CLR ENABLED’, ‘1’
GO
RECONFIGURE
GO
ALTER Database DatabaseName SET TRUSTWORTHY ON
GO

8.  Since we are using the System.DirectoryServices namespace, we need to allow SQL to recognize this as an assembly

SET NOCOUNT ON
GO
USE Master
GO
CREATE ASYMMETRIC KEY SystemDirectoryServicesKey FROM EXECUTABLE FILE = 'C:WINDOWSMicrosoft.NETFrameworkv2.0.50727System.DirectoryServices.dll'
GO
--create logins for special goals
CREATE LOGIN SQLCLRSysDirServLogin FROM ASYMMETRIC KEY SystemDirectoryServicesKey
GO</pre>
-- grant necessary (UNSAFE) permissions
GRANT UNSAFE ASSEMBLY TO SQLCLRSysDirServLogin
GO
USE
GO

CREATE ASSEMBLY [System.DirectoryServices]
FROM 'C:WINDOWSMicrosoft.NETFrameworkv2.0.50727System.DirectoryServices.dll'
WITH PERMISSION_SET = UNSAFE
GO

9.  Go back to Visual Studio, select the “Debug” drop down and change that to “Release”.

10. Save. Hit F5. Visual Studio will both build it and deploy it automatically to the database specified.

11. In SQL Management Studio, query your database with the following statement:

SELECT IsUserPartOfADGroup(‘domainnameusername’, ‘Group To Check’)

A note:

• This function is meant to return a 1 if the specified user does exist in the specified Active Directory group, a 0 if not, and -1 if an error occurred. If an error occurred, it will right it in the Windows Event Log.

Further Resources:

How to Avoid 1000 Rows limitation when querying Active Directory – deals with additional Active Directory functions

This is my first experience in the world of blogging and hope to bring some ideas and technical knowledge to the web as the web has been a major help in my development. I’m writing this from Word 2007 since it’s able to plug-into WordPress.com.

I believe I should start out by introducing myself: I’m currently engaged to the most wonderful woman in the world and we are getting married in December. I’m currently working as a Software Developer near Columbus, Ohio developing custom solutions and customizations working primarily with all things Microsoft. My company specializes in Microsoft Dynamics SL, GP, and CRM. I love learning and experimenting with new technologies and hope to blog about some of my experiences here.

I hope you enjoy.