SQL Server - How do I select just the date portion of a datetime field

There are a few ways to do this, but I find the easiest is to use the float version of a datetime and crop off the decimal portion (right of the decimal place is the time portion)

DECLARE @currentDate DateTime
SET @currentDate = Cast(Floor(Cast(GetDate() as Float )) As DateTime)

"Failed to pause full-text catalog for backup" while backing up a database

So you're trying to back up your database and you get the following error:

Failed to pause full-text catalog for backup. Backup was aborted. Check to make sure Microsoft Full-text Service is running properly and SQL server service have access to full-text service.

There are a couple of things that could be up here. Try all of the following and see if that get's you out of this:

1. Check if the full text service is running. This can be found by opening up the windows services and locating either "SQL Server Full Text Search" or "Microsoft Search Service". If it's not running or disabled then this may be your problem- Retry the backup.

2. Ensure full text catalog is enabled on the databases by running the following command:

exec sp_fulltext_database 'enable'

Retry the backup.

3. If all of the above fails take a note of how the full text catalog is set up on the database in question. It should be accessible via Storage -> Full Text Catalogs. When you see what tables and fields it references try dropping and recreating the full text catalog. Retry the backup.


Hope this helps!

"The virtual directory specified already exists"... but it doesn't!

I've come across this issue intermittently on some servers, but I haven't figured out yet why it happens. The times I've seen it happen is when the virtual folder wasn't created with all the permissions required, and then deleting it seems to leave a remnants of it behind. An example of this is when you cannot locate the virtual directory but can see it referenced by an app pool.

So, how do you get rid of it?

9 times out of 10 the following works for me. Let's say the new virtual directory is called "MyDir" and was located in the web site "My Web"

- Open up a command prompt
- Type in the following command:

IIsVDir /delete "My Web"/MyDir

Sometimes if that doesn't work creating the virtual directory (using the same name - MyDir in this example) and running the above command again usually works.

If anyone can shed any light on why this remnants happens please do.

How to programatically move the mouse in C#

.Net gives you access to the mouse via the "Cursor" class. You can interact with the mouse position like this:


Cursor.Position = new Point(Cursor.Position.X + 10, Cursor.Position.Y + 10);

Easy peesy

DateTime.Min != SqlDateTime.Min

Yes, as the title says, .Net DateTime Minimum does not equal Sql Servers equivalent. For whatever reason you come across this gem of an issue you have a couple of options to get around it.

1. Use a .net Nullable datetime instead. i.e. Declare your "DateTime" as "DateTime?". Putting question marks after a lot of .Net variable types in C# turns them into nullable types.

2. If you really do need the min date, use SqlDateTime.Min.Value. "Value" gives you access to a DateTime type containing SQLs min date.

SQL Server - Select rows of a "max date" from a table (using ROW_NUMBER() OVER)

I often come across different requirements where I need to get the "top row" where certain criteria exists. It often applies to VAT Rates, Exchange Rates, even historical data where a different record may apply depending on the scenario. For this example, let's use VAT rates.

Let's create sample data using the following:

create table #myvattable (vatname nvarchar(50), effectivedate datetime)
insert #myvattable values('Rate A', '01/01/2009')
insert #myvattable values('Rate B', '01/01/2009')
insert #myvattable values('Rate C', '01/01/2009')
insert #myvattable values('Rate A', '01/02/2009')
insert #myvattable values('Rate B', '01/02/2009')
insert #myvattable values('Rate B', '01/02/2008')


So, we have several instances of the same "Rate" in the table that have different effective dates. Now, let's take this requirement:

I want to retrieve all VAT rates applicable for a certain date. How do we do this?


Step 1 - use a row_number() clause on your dataset:

select * from
(
select row_number() over (partition by a.vatname order by a.vatname, a.effectivedate desc) as rownum,
a.vatname, a.effectivedate
from #myvattable a
)
tbl



This simply puts a row_number clause on each row partitioning by the vatname. This returns a result set similar to this:

rownum vatname effectivedate
------ ------------- -----------------------
1 Rate A 2009-01-02 00:00:00.000
2 Rate A 2009-01-01 00:00:00.000
1 Rate B 2009-01-02 00:00:00.000
2 Rate B 2009-01-01 00:00:00.000
3 Rate B 2008-01-02 00:00:00.000
1 Rate C 2009-01-01 00:00:00.000


Ok, so what does this do for us? It effectively ranks the rows by each vatname so that we can see which ones are most applicable. Basically we want all the 1's.

Step 2 - Filter the rownums.
So our query becomes this:

select * from
(
select row_number() over (partition by a.vatname order by a.vatname, a.effectivedate desc) as rownum,
a.vatname, a.effectivedate
from #myvattable a
)
tbl
where rownum = 1


Ok, pretty much there now. The only step really that is left is... what if someone wants historical data? This query is fixed to the latest most applicable vatrate.


Step 3 - Make the date flexible

select * from
(
select row_number() over (partition by a.vatname order by a.vatname, a.effectivedate desc) as rownum,
a.vatname, a.effectivedate
from #myvattable a
where effectivedate <= @DATEVARIABLE )
tbl
where rownum = 1


So, @DATEVARIABLE could be a parameter/variable... or, even better, a field from another joined table.

How to calculate the width/height of a string in a particular font

- Follow up from the listbox width issue -

This applies to mainly asp.net, but the technique for winforms isn't drastically different. What we need to use is a Graphics object to measure a string width. Here's how:


// Bitmap is solely required for creating the graphics object
Bitmap TextBitmap = new Bitmap(1, 1);
Graphics g = Graphics.FromImage(TextBitmap);

// Create the font relative to the text (let's say Arial 8)
Font myFont = new Font("Arial", 8);
SizeF fontSize = g.MeasureString("This is a test string", myFont);



Done. The values you need are fontSize.Height and fontSize.Width.