    SELECT DATABASE_PRINCIPAL_ID(&#39;role&#39;)
    --or
    IF DATABASE_PRINCIPAL_ID(&#39;role&#39;) IS NULL

[USER_ID][1] is deprecated and could break. [CREATE ROLE][2] indicates SQL 2005+ so it&#39;s OK


  [1]: http://msdn.microsoft.com/en-us/library/ms181466.aspx
  [2]: http://msdn.microsoft.com/en-us/library/ms187936%28SQL.90%29.aspx

    if not exists (select 1 from sys.database_principals where name=&#39;role&#39; and Type = &#39;R&#39;)
    begin
    CREATE ROLE role
        AUTHORIZATION MyUser;
    end



While updating for loops to for-each loops in our application, I came across a lot of these &quot;patterns&quot;:

    for (int i = 0, n = a.length; i &lt; n; i++) {
        ...
    }

instead of

    for (int i = 0; i &lt; a.length; i++) {
        ...
    }

I can see that you gain performance for collections because you don&#39;t need to call the *size()* method with each loop. But with arrays??

So the question arose: is `array.length` more expensive than a regular variable?


What is the Cost of Calling array.length

How can i use the server.mappath method in a C# class library class ,which acts as my BusinessLayer for My ASP.NET WEbsite

Server.Mappath in C# classlibrary

I&#39;m trying to figure out how I can check if a database role exists in SQL Server.  I want to do something like this:


    if not exists (select 1 from sometable where rolename=&#39;role&#39;)
    begin
    CREATE ROLE role
        AUTHORIZATION MyUser;
    end

What table/proc should I use here?

How do I determine if a database role exists in SQL Server?

I'm trying to figure out how I can check if a database role exists in SQL Server. I want to do something like this:
<pre><code class="hljs language-sql">if not exists (select 1 from sometable where rolename='role')
begin
CREATE ROLE role
 AUTHORIZATION MyUser;
end
</code></pre>
What table/proc should I use here?

For `INSERT`, `UPDATE` and `DELETE` SQL statements executed directly against the database, most database providers return the count of rows affected. For stored procedures, the number of records affected is always `-1`.

How do we get the number of records affected by a stored procedure?





How can I get the number of records affected by a stored procedure?

Im calling a SQL stored procedure from a piece of C#.net code:

    SqlHelper.ExecuteDataset(sqlConnection, CommandType.StoredProcedure, STORED_PROC_NAME, sqlParameters);

where the `sqlParameters` variable is defined as:

            SqlParameter[] sqlParameters = new SqlParameter[SQL_NUMBER_PARAMETERS];

            Log.Logger.Debug(string.Format(&quot;Running proc: {0} &quot;, STORED_PROC_NAME));

            SqlParameters[0] = new SqlParameter(&quot;fieldID&quot;, SqlDbType.BigInt );
            SqlParameters[0].Value = fieldID;
            SqlParameters[0].Direction = ParameterDirection.Input;

I need to now pass in another two parameters to this Stored Proc, (both are of type `SqlDateTime`), which are going to *NULL* in this case.

Thanks,

IN

How to pass a null variable to a SQL Stored Procedure from C#.net code

This seems like a duplicate even as I ask it, but I searched and didn&#39;t find it. It seems like a good question for SO -- even though I&#39;m sure I can find it on many blogs etc. out there. SO will have more of a debate than you can get on a blog. 

I&#39;m running into an issue with a join: getting back too many records. I think of this as &quot;expansion&quot;. I added a table to the set of joins and the number of rows expanded, way too much. Usually when this happens I add a select of all the ID fields that are involved in the join. That way it&#39;s pretty obvious where the expansion is happening and I can change the ON of the join to fix it. Except in this case, the table that I added doesn&#39;t have an ID field. To me, this is a problem. But perhaps I&#39;m wrong. 

The question: should every table in a database have an IDENTITY field that&#39;s used as the PK? Are there any drawbacks to having an ID field in every table? What if you&#39;re reasonably sure this table will never be used in a PK/FK relationship? 

Related, but not duplicate: https://stackoverflow.com/questions/932913/when-having-an-identity-column-is-not-a-good-idea

Apparently this debate has been [going on for a while][1]. Shoulda known. 

[This post][2] (surrogate vs. natural keys) is also relevant.


  [1]: http://en.wikipedia.org/wiki/Surrogate_key
  [2]: https://stackoverflow.com/questions/63090/surrogate-vs-natural-business-keys

in general, should every table in a database have an identity field to use as a PK?

I have a column that looks something like this:

    CASE
        WHEN col1 &gt; col2 THEN SUM(col3*col4)
        ELSE 0
    END AS some_product

And I would like to put it in my GROUP BY clause, but this seems to cause problems because there is an aggregate function in column.  Is there a way to GROUP BY a column alias such as `some_product` in this case, or do I need to put this in a subquery and group on that?

SQL GROUP BY CASE statement with aggregate function

I have a couple of properties in `C#` which are `double` and I want to store these in a table in SQL Server, but noticed there is no `double` type, so what is best to use, `decimal` or `float`?

This will store latitude and longitude values, so I need the most accurate precision.

Thanks for the responses so far.

What represents a double in sql server?

We are dealing with an application that needs to handle global time data from different time zones and daylight savings time settings. The idea is to store everything in UTC format internally and only convert back and forth for the localized user interfaces. Does the SQL Server offer any mechanisms for dealing with the translations given a time, a country and a timezone?

This must be a common problem, so I&#39;m surprised google wouldn&#39;t turn up anything usable.

Any pointers?




Content Type	Original Author	Original Content on Stackoverflow
Question	Jon Kruger	View Question on Stackoverflow
Solution 1 - Sql	gbn	View Answer on Stackoverflow
Solution 2 - Sql	George Mastros	View Answer on Stackoverflow

How do I determine if a database role exists in SQL Server?

Sql Problem Overview

Sql Solutions

Solution 1 - Sql

Solution 2 - Sql

Server.Mappath in C# classlibrary

What is the Cost of Calling array.length

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