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A while ago I posted a query to create a list of all the Integration Services packages deployed to the MSDB.  I am now using that query to take it a step further.

If you’ve been using SSIS for a while you’ve probably noticed that the Management Studio doesn’t like to delete Integration Services folders that are not empty.  In fact, it will politely ask you if you’re sure that you want to delete the folder on which you’ve just selected the “Delete” option through the right-click menu.

Right-click pop-up menu on SSIS folder

I am sure I want to delete this non-empty SSIS folder

So you click the Yes button.  But then it shows you the following message:

SSIS folder ‘FolderWithSubfolders’ contains packages and/or other folders. You must drop these first. (Microsoft SQL Server Native Client 10.0)

Graphically it looks like this:

Object Explorer pop-up: you can't delete SSIS folders that contain packages or other folders

And this message can be really annoying if you’ve got a main folder with, let’s say, five subfolders, and each subfolder contains about 20-30 packages.  If you want to delete this folder you first need to delete each package separately and then delete the five subfolders, and then you can finally delete the main folder.  And all that through the right-click pop-up menu because you can’t just select the object in the Object Explorer and hit the Delete button on the keyboard – it doesn’t have an action on SSIS objects…

So, I wasn’t planning on doing such a job manually and came up with the following stored procedure.

It’s probably a bit long but don’t run away just yet, I will explain what’s going on down below the code, and there are some comments in the code as well.

/*
DESCRIPTION: Deletes all folders and packages under, and including, specified folder.
WRITTEN BY:  Valentino Vranken
CREATED:     2010-02-28
VERSION:     1.0
USAGE:
  -- mind the forward slash
  EXEC dbo.SSIS_RecursiveDeleteFolder '/FolderWithSubfolders'
  -- to delete a subfolder
  EXEC dbo.SSIS_RecursiveDeleteFolder '/FolderWithSubfolders/ASubfolderWithPackages'

COPIED FROM: http://blog.hoegaerden.be

Note 1: folder names are not case-sensitive
Note 2: uses system tables and (undocumented) stored procedures located in MSDB.
Note 3: this code was written for SQL Server 2008. For 2005:
  o sysssispackagefolders -> sysdtspackagefolders90
  o sysssispackages -> sysdtspackages90
  o sp_ssis_deletefolder -> sp_dts_deletefolder
  o sp_ssis_deletepackage -> sp_dts_deletepackage
*/
CREATE PROCEDURE dbo.SSIS_RecursiveDeleteFolder
    @Folder varchar(2000)
AS
BEGIN
    set nocount on;

    declare @foldersToDelete table
    (
        folderid uniqueidentifier,
        Lvl int
    );

    declare @packagesToDelete table
    (
        PackageName sysname,
        folderid uniqueidentifier,
        Lvl int
    );

    --retrieve list of folders to be deleted
    with ChildFolders
    as
    (
        select PARENT.parentfolderid, PARENT.folderid, PARENT.foldername,
            cast('' as sysname) as RootFolder,
            cast(PARENT.foldername as varchar(max)) as FullPath,
            0 as Lvl
        from msdb.dbo.sysssispackagefolders PARENT
        where PARENT.parentfolderid is null
        UNION ALL
        select CHILD.parentfolderid, CHILD.folderid, CHILD.foldername,
            case ChildFolders.Lvl
                when 0 then CHILD.foldername
                else ChildFolders.RootFolder
            end as RootFolder,
            cast(ChildFolders.FullPath + '/' + CHILD.foldername as varchar(max))
                as FullPath,
            ChildFolders.Lvl + 1 as Lvl
        from msdb.dbo.sysssispackagefolders CHILD
            inner join ChildFolders on ChildFolders.folderid = CHILD.parentfolderid
    )
    insert into @foldersToDelete
    select F.folderid, F.Lvl
    from ChildFolders F
    where F.FullPath like @Folder + '%';

    --retrieve list of packages to be deleted
    with ChildFolders
    as
    (
        select PARENT.parentfolderid, PARENT.folderid, PARENT.foldername,
            cast('' as sysname) as RootFolder,
            cast(PARENT.foldername as varchar(max)) as FullPath,
            0 as Lvl
        from msdb.dbo.sysssispackagefolders PARENT
        where PARENT.parentfolderid is null
        UNION ALL
        select CHILD.parentfolderid, CHILD.folderid, CHILD.foldername,
            case ChildFolders.Lvl
                when 0 then CHILD.foldername
                else ChildFolders.RootFolder
            end as RootFolder,
            cast(ChildFolders.FullPath + '/' + CHILD.foldername as varchar(max))
                as FullPath,
            ChildFolders.Lvl + 1 as Lvl
        from msdb.dbo.sysssispackagefolders CHILD
            inner join ChildFolders on ChildFolders.folderid = CHILD.parentfolderid
    )
    insert into @packagesToDelete
    select P.name, F.folderid, F.Lvl
    from ChildFolders F
        inner join msdb.dbo.sysssispackages P on P.folderid = F.folderid
    where F.FullPath like @Folder + '%';

    --use cursor to loop over objects to be deleted
    declare objectsToDelete_cursor cursor
    for
        select P.folderid, P.Lvl, P.PackageName, 'P' as ObjectType
        from @packagesToDelete P
        UNION ALL
        select F.folderid, F.Lvl, null, 'F'
        from @foldersToDelete F
        order by Lvl desc, ObjectType desc;

    open objectsToDelete_cursor;

    declare @folderid uniqueidentifier;
    declare @lvl int;
    declare @packageName sysname;
    declare @objectType char;

    fetch next from objectsToDelete_cursor
    into @folderid, @lvl, @packageName, @objectType;

    while @@FETCH_STATUS = 0
    begin
        if @objectType = 'F'
        begin
            print 'exec msdb.dbo.sp_ssis_deletefolder '
                + cast(@folderid as varchar(max));
            exec msdb.dbo.sp_ssis_deletefolder @folderid;
        end
        else
        begin
            print 'exec msdb.dbo.sp_ssis_deletepackage '
                + @packageName + ', ' + cast(@folderid as varchar(max));
            exec msdb.dbo.sp_ssis_deletepackage @packageName, @folderid;
        end

        fetch next from objectsToDelete_cursor
        into @folderid, @lvl, @packageName, @objectType;
    end;

    close objectsToDelete_cursor;
    deallocate objectsToDelete_cursor;
END

Before trying to dismantle this stored procedure, I recommend you to read my previous article on retrieving the list of packages.  That already explains half of the code, if not 75%.

Our mission is to find a way to recursively delete packages and folders contained in a specified folder.  To be able to loop over those objects in the correct order (from the deepest level up until the level of the folder specified), the SP creates two table variables: one to hold all folders under the specified folder (@foldersToDelete) and one to hold the packages under the specified folder, including all subfolders (@packagesToDelete).

Based on those two lists I create a cursor that joins these two together, taking their level and object type into consideration.  That’s important because we first need to delete the packages in the lowest level folder, followed by their containing folder, then move one level up and do the same.

We then use the cursor to loop over the packages and folders and use two undocumented system stored procedures – one for each object type- to delete the package or folder.  These system SPs are located in the MSDB.  Here’s how they are defined:

ALTER PROCEDURE [dbo].[sp_ssis_deletefolder]
  @folderid uniqueidentifier
AS

ALTER PROCEDURE [dbo].[sp_ssis_deletepackage]
  @name sysname,
  @folderid uniqueidentifier
AS

As you can see, the parameters for these procedures are not that complicated.  Both of them expect a uniqueidentifier as identification for the folder.  That’s okay, these IDs are stored in the msdb.dbo.sysssispackagefolders table and retrieved by our queries to create the list of to-be-deleted objects.

Furthermore, the sp_ssis_deletepackage SP expects the name of the package to be deleted.  Not a problem either, those names are obtained from the msdb.dbo.sysssispackages table.

Note for SQL Server 2005 users: this code was written for SQL Server 2008.  The system stored procedures and system tables exist in 2005 as well, but they have different names.  See the comment header of my SP for more details.

So, let’s give it a little test.  Following screenshot shows the setup.  What I will do is use the stored procedure to delete the FolderWithSubfolders folder.  If you’ve been paying close attention, that is the same folder which I tried to delete manually through the Management Studio’s right-click menu (see first screenshot above).

Overview of my deployed folders and packages

After creating the SP, I ran following command:

EXEC dbo.SSIS_RecursiveDeleteFolder '/FolderWithSubfolders'

And that gave me the following output in the Messages pane:

exec msdb.dbo.sp_ssis_deletepackage AnotherPackage, 7F38288D-4370-40A8-80E3-E92283033E4C

exec msdb.dbo.sp_ssis_deletepackage Package, 7F38288D-4370-40A8-80E3-E92283033E4C

exec msdb.dbo.sp_ssis_deletefolder 4102ED59-ED75-4D93-BBAE-0A162447BF02

exec msdb.dbo.sp_ssis_deletefolder 7F38288D-4370-40A8-80E3-E92283033E4C

exec msdb.dbo.sp_ssis_deletefolder C156B436-8C78-4BF9-99F9-5ABFAB10C405

I have deliberately put a couple of print commands in the stored procedure to dump the commands that are actually being executed.  This gives us a good idea of what’s going on.

That’s it for now folks.  Thank you for reading this, and if you found it useful or you’ve got some questions about it: post a comment!

Have fun!

Valentino.

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A while ago I had been playing a bit with the new spatial data types in SQL Server 2008.  Not only can SQL Server store such data, it can also visualize it.  So I had come up with the following query:

select geometry::STPolyFromText
('POLYGON((1 1, 1.5 1.85, 2.5 1.85, 3 1, 2.5 0.15, 1.5 0.15, 1 1),
(1.5 1.5, 1.5 0.5, 1.7 0.5, 1.7 0.9, 2.3 0.9, 2.3 0.5, 2.5 0.5, 2.5 1.5, 2.3 1.5,
2.3 1.1, 1.7 1.1, 1.7 1.5, 1.5 1.5))', 0);

Running that in the Management Studio produces something like this on the Spatial results tab:

Hoegaerden - the polygon

I’m using the STPolyFromText function to produce a six-sided polygon with a letter H in the center.  To get to the result, I’m passing a bunch of XY coordinates to the function.  A line gets drawn between two coordinates following each other.

The first list of coordinates (the first list of numbers enclosed in round brackets) creates the hexagon while the second list produces the letter H.  Each list of coordinates thus represents one polygon.   The starting XY coordinate must be equal to the ending coordinate to form a closed shape.  The shape is then filled with a color.  Overlapping shapes will be filled using different colors, as shown above.

Producing these coordinates was quite interesting: to be able to calculate the angled sides of the hexagon I used the following formulas.

With S being the length of one side:

Width = 2 * S

Height = S * SQRT(3)

Note: these formulas are only applicable when the hexagon is rotated as shown above.

I needed to know these distances to be able to calculate how much I should increase the X/Y coordinates to get to the next connector.

Okay, enough theory, back to the story now.

Q: “So, why are you creating a helipad platform?”

A: No, it’s not supposed to look like a helipad platform.  The shape resembles the beer coasters for the beer called Hoegaarden.  And those coasters always have a funny drawing or comment on them.  Let’s see if I can find one that’s understandable for non-native Dutch-speakers…

(And half an hour later – turns out it’s really not easy to find one without text – luckily they’ve also created some in English!)

Hoegaarden beer coaster

Initially I was planning on writing a longer article about the spatial data types but hadn’t found the time to do it yet.  And then a couple of days ago I came across a challenge that made me think of this query and so now I’m publishing it in this post.

The challenge to which I’m referring was started by Itzik Ben-Gan and is called Geekiest Sig Challenge.  The point is to use the new SQL Server spatial data types to create a signature for yourself.  Well, a perfect description for my query!

I was happy to just get an H on there, getting those coordinates right without first putting it on paper is really a challenge :-)   And on top of that, I was never any good at drawing.  I remember in secondary school we got an assignment to draw a tree.  Any tree.  So at home I looked out the window and started drawing the tree.  I ended up with the most atrocious thing I’d ever seen (well, that may be a bit exaggerated), it could have starred in a Hitchcock movie straight away, really spiky, and probably spooky when encountered in the dark and with the right background noises playing.

Anyway, what I wanted to say, some people are just talented: check out this submission by Michael J. Swart!  No further words needed.

Right, enough geeky stuff to close the week, and remember: have fun!

(Hmm, now I’ve got something to build my favicon from…)

Valentino.

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Using the Management Studio (SSMS) I just received an error which I hadn’t seen before.  Here’s what I was doing.

On my freshly-installed Windows 7 64-bit machine I have both SQL Server 2008 SP1 and SQL Server 2008 R2 (NOV CTP) running (both 64-bit as well).  And I just installed the new Contoso data warehouse and OLAP DB.

After setting up the data source connection of the Contoso_Retail OLAP database and processing it successfully, the next logical step is to try and browse the cubes, through the Management Studio.  So that’s what I tried, but unfortunately it gave me the following error:

Invalid class string (Exception from HRESULT: 0x800401F3 (CO_E_CLASSSTRING)

Hmm, okay, that doesn’t look good!  “Invalid class string”, what does that mean??

So I tried the link that says “Click here to see detailed error information”, which gave me this:

Error pop-up: I don't see the details

I’m sorry, but where exactly are the details in this message?

Luckily a quick internet search gave me the solution (and reminded me of something which I actually knew but just didn’t think of because it’s all running in a totally new environment).

To browse cubes, SSMS is using a component from the “Microsoft Office 2003 Web Components” package, whatever that that means.

And the solution (as described here) is to:

  • Open the list of installed programs (Windows Key + R > appwiz.cpl > enter)
  • Locate the Office 2003 Web Components, right-click and select Change
  • Follow the wizard to repair/reinstall the components

Programs and Features

And now I am able to browse the cube without any issue!

Have fun!

Valentino.

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Sometimes my posts are over 20 pages long when pasted into a Word document.  That’s when I call them article, or tutorial.  Other times I post real quickies about little things that have annoyed me in the past, because I had to spend too much time looking for a solution to a certain issue, or just because they are not very obvious and I can image fellow developers doing a search on the internet on that specific subject.

This post is one of the latter.

In a SQL Server Integration Services project, have you ever wondered how on earth you can get files into that Miscellaneous folder?  When you right-click on the folder in the Solution Explorer, nothing happens, no pop-up menu.

Well, the answer is simple, once you know it.

All you need to do is go one level up in the tree and right-click the Project node in the Solution Explorer.  In the menu that appears, select Add > Existing Item….

How to add a file to the SSIS Miscellaneous folder

In the pop-up window, navigate to any file that you’d like to add to the project.  Files of a different type than the usual SSIS files such as .dtsx and .ds are automatically added under the Miscellaneous folder.  When adding files, they will be automatically copied to the SSIS project folder, no matter where they were stored originally.  See, not that complicated… once you know it!

In the following screenshot I’ve added three different file types to the folder, just to prove that it’s working.

Miscellaneous folder with some files added to it

I like using this folder to store files that belong with that particular project.  Examples of those are configuration files, XSLT files for complex XML conversions, and also the SQL scripts that create my databases.  Each time when I make schema changes, I update the scripts.  And as I’m using TFS integration, I can rest assured that I always have a backup of my files.  (At least, assuming the TFS team is doing their job – this is usually beyond my responsibility :-) )

Speaking about TFS, watch out if you use Business Intelligence Development Studio 2008 to connect to Team Foundation Server 2005!  There’s an interesting setting in the Options screen (through the Tools menu), located in the Source Control > Visual Studio Team Foundation Server page.  This setting is called Get latest version of file on check out.

Get latest version of item on check out

However, there’s one caveat!  On TFS2005 it doesn’t do anything!  If you’re not aware of that, you may get an annoying surprise when you’re trying to check in your changes because you may have been working on an outdated version of your package!  And as you probably already know: merging two versions of an SSIS package is, well, what shall I call it, a challenge?

Another setting that helps you to avoid the issue described above is located under Source Control > Environment and is called Get everything when a solution or project is opened.  Activate this setting and each time when you open your project, you’ll get a popup window which allows you to Get the latest version of the files.

Get evrything when a solution or project is opened

That leaves one more possible conflict situation.  If someone changes a package on the same day as you, the second person will need to explicitly do a Get Latest Version or he/she will be working on an outdated version.  So, communicate with your team mates so that you know if someone has gotten an assignment that collides with yours.  Of course, this last problem is just a theoretical possibility.  In teams, work is usually divided so that developers do not need to work with more than one person on the same piece of code.  The same logic applies to SSIS packages.

And remember, have fun!

Valentino.

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With great pleasure I’d like to share with you that my employer has approved my request to attend the SQL PASS European Conference! (Thank you Ordina :-) )

This event will take place at 21-23 April 2010 in Neuss, Germany.

PASS European Conference: April 21 - 23, 2010

I’m really looking forward to this, I’m sure it will be three days with a lot of learning, a lot of networking and a lot of fun!

Sessions I’m hoping to see (in no particular order):

Sessions are currently still being added to the agenda, so I’ll update my list here as well when needed.

If you’re going too and you’re from Belgium: have a look at the Belgian SQL Server User Group site for a discount code!

Ow, and post a comment here so we that can have a chat over there!

Have fun!

Valentino.

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I usually don’t write posts just to mention a link to another site.  Except when I’ve come across articles which are so good that I want everyone to know about them.  Here are a couple of articles in that particular category.

What Does Microsoft Do With Those Memory Dumps?

The first one is written by Adam W. Saxton, a member of the Microsoft Customer Service and Support (CSS) SQL Server Escalation Services team.

The subject of the post is an issue that developers of Reporting Services reports may come across: “InvalidReportParameterException with Data Driven Subscription”.  The report complains about an invalid parameter while the parameters seem to be okay, visually.  Then the author goes on to describe the actual issue: trailing spaces!  If you’ve been doing BI for a while, this is a quite common issue.  Adam also shows the difference between the LEN() and the DATALENGTH() functions.

But that’s not the reason that I’m mentioning that article here.  The best part starts following the Summary chapter, and is entitled Techie Details.  In that extra chapter he shows how the CSS team uses those crash memory dumps which I’m sure you’ve all seen now and then. 

I won’t give you any details about that, just have a look at the article.  If you’re a developer, there’s some very valuable information there!

I am definitely looking forward to seeing his pre-conference session at the SQL PASS European Conference in Germany this year: Tackling Top Reporting Services Issues!

Some Crazy Code Samples

The second article that I’d like to mention here is written by Phil Factor, a regular at the Simple-Talk site.

This article is called Laying out SQL Code and mentions some database naming conventions and T-SQL coding layout, as the title already implies.  Even if you’re not interested in that (although as a serious developer you should be!!), the article is worth the effort of reading just for its code samples.

Here’s my favorite one:

CREATE TABLE "╚╦╩╗" ( "└┬┴┐" nvarchar(10))
DECLARE @ nvarchar(10)  set @='═'
INSERT  INTO "╚╦╩╗"
        ( "└┬┴┐" )
        SELECT  replicate(@,5)

SELECT  *
FROM    "╚╦╩╗"

And just to prove to you that this really is valid code, here’s the result:

Result of crazy query

So, how about that database for that plumbing company? :-)

BTW: when running that code without paying attention to the details (such as what DB your SSMS is connected to), you may end up with something like this:

Silly table stored in master DB - that's not a best practice! 

So you may want to clean up after running the query using this statement:

drop table "╚╦╩╗"

Have fun!

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Introduction

This article is aimed at report developers who are used to develop reports using relational databases and have gotten a first-time assignment to develop reports on OLAP cubes.

It demonstrates how to build a report using SQL Server Reporting Services 2008 with data coming from an OLAP cube running on SQL Server Analysis Services 2008.

The OLAP database used in the article is called “Adventure Works DW 2008”, available for download at CodePlex.

If you’re fairly new to Reporting Services (aka SSRS) and you find that this article is going a bit too fast, I’d like to point you to my other article which explains how to build a report that’s retrieving data using regular stored procedures.

OLAP <> OLTP

When people are talking about databases, what they are usually referring to are “regular” relational OLTP databases.  OLTP stands for Online Transaction Processing.  As the name implies, these types of databases are built to handle many simultaneous transactions (consisting of actions such as inserts, updates, deletes) in real-time.  I’m sure you’re familiar with these types of database so I won’t go further into them.

OLAP (Online Analytical Processing) on the other hand is a totally different story.  OLAP cubes are built to answer multi-dimensional analytical queries as fast as possible.  For that purpose, what you can find in such a database are measures (these are the numbers) stored in cubes, and dimensions which allow filtering the measures.  This filtering is often referred to as slicing and dicing.  Furthermore, OLAP cubes contain pre-aggregated data, again to be able to answer queries as fast as possible.

Let’s make this clear with an example.  Imagine the following request:

“Give me the sum of all sales of product X for period Y in country Z.”

Three dimensions can be recognized in that request: “product X” is found in the Product dimension, “period Y” in the Date dimension and “country Z” in the Geography dimension.  (I’ve used the actual dimension names as they are called in the Adventure Works OLAP database.)

Each dimension consists of attributes and attribute hierarchies and it’s those attributes that you’re actually referring to when building an MDX query.  MDX stands for Multidimensional Expressions and that is the language used to query an OLAP database, just like you use SQL to query a relational database.

Looking at our example, what we need is for the Product attribute in the Product dimension to be equal to X.  An attribute in a dimension can also be written as [Dimension].[Attribute], thus we also want [Date].[Date] to be equal to Y and [Geography].[Country] equal to Z.

As for the measure part, that’s what “the sum of all sales” is referring to.  When looking at the measures available in the Adventure Works cube, one of the measures that would fulfill the request is the Reseller Sales Amount in the Reseller Sales measure group.  The Analysis Services engine searches the cube and retrieves the aggregated number for [Measures].[Reseller Sales Amount] available at the intersection of [Product].[Product] X, [Date].[Date] Y and [Geography].[Country] Z.

OLAP cubes are usually, although not necessarily, build on top of a data warehouse.  In SQL Server, a data warehouse is still a relational database, unlike an OLAP cube, but the table structure is different from an OLTP database.  A data warehouse contains tables that represent dimensions and other tables that contain the facts.  The facts are the numbers, so the measures that were mentioned earlier.  This is called a dimensional model.  Dimensional modeling was invented by Ralph Kimball, one of the pioneers in data warehousing.  For completeness I’d like to mention that another data warehousing approach was described by Bill Inmon.  I’ll leave it up to you to do some research on both approaches and decide for yourself which one you prefer, possibly even a mix of both.

As far as the “Adventure Works DW 2008” OLAP database is concerned, it’s built on top of the AdventureWorksDW2008 dimensional database.

Okay, I believe this theoretical explanation was sufficient for now, let’s start with the report!

Your First Report

Business Requirements

You’ve gotten the assignment to create a report that shows the reseller sales numbers by region.  The highest level to be shown is Country, with drilldown through State/Province to City.

Creating The Shared Data Source

Just like when building reports on OLTP databases, we’re not going anywhere without a Data Source.  I’m going to create a Shared Data Source called OLAP_AdventureWorks.rds:

Shared Data Source connecting to Adventure Works OLAP Database

The Type that we need is Microsoft SQL Server Analysis Services, which is the SQL Server service that’s running the OLAP databases.  Furthermore I’ve selected the “Adventure Works DW 2008” database.

Connection Properties specifying the Adventure Works DW 2008 OLAP database

There’s no need to type the database name yourself.  After you’ve provided sufficient credentials in the Credentials page, you can just select it from the dropdown in the Connection Properties screen.  This screen is opened by clicking that Edit button on the Shared Data Source Properties window.

Your First OLAP Dataset

I’ve created a new report called FirstOLAPReport.rdl.  In that report I’ve specified that I’ll be using the Shared Data Source created earlier.  This source is known as srcAdventureWorksOLAP in my report.

Next step is to create the dataset.  I’m calling it dsResellerSalesByRegion.  As this is our first OLAP report, we’re not going to write the MDX ourselves but we will use the Query Designer which is opened by clicking the button that has the words Query Designer printed on them, how difficult can that be?!

How to open the MDX Query Designer

The BIDS knows that it should open the MDX Query Designer because our data source is connecting to an Analysis Services server.  All we need to do now is to drag the measures and dimension attributes that we require into the area marked with “Drag levels or measures here to add to the query.”.

Let’s start by dragging our measures into that area.  We need two measures, both located in the Reseller Sales measure group.  They are called Reseller Order Quantity and Reseller Sales Amount.  Following screenshot shows the situation after the first measure has been added.  The second measure was being dragged into it as well.  When dragging items into the area, a vertical blue line appears to indicate where the item can be added.

MDX Query Designer: dragging a measure into the query

Next I’m going to drag the Geography hierarchy, located in the Geography dimension, into the design area.

MDX Query Designer: dragging a hierarchy into the query

Now we’ve got all the data we need for our report.

As you have noticed, the Query Designer automatically executes the query each time it gets modified when you’re dragging an item into the design area.  If you don’t want this behaviour, it can be switched off by clicking the Auto Execute button in the toolbar (indicated by a red 1 in the screenshot below).

Query Designer toolbar

Another interesting button is the Design Mode button (indicated by a green 2).  This one allows you to toggle between the graphical designer and the text editor.  By clicking it you can see the actual MDX query that the designer has prepared for you.

As you can see, the query is nicely formatted using capitals for the keywords and so on.  Well, no, actually it’s the worst editor around!  No syntax coloring, no multi-line formatting, nothing.  So if you are going to take a close look at the query, I recommend you to use the Management Studio.  Connect to your Analysis Services server, locate your database and right-click it in the Object Explorer.  Then choose New Query > MDX and paste the query into that new window.  You’ll still need to manually break it down into different lines but at least you get syntax coloring.  Furthermore, if you’re going to make manual modifications to it, you’ve got some command completion and error indicators as well.

Please take into account that once you’ve made manual changes to your query, you cannot switch back to the graphical designer.  Well, you can, but you will lose all manual modifications.  Don’t worry about doing it accidentally though, a nice pop-up will warn you:

Warning message when switching back to design mode.

Something else that you’ll also notice is that the results displayed in the Query Designer and those displayed in the Management Studio are not exactly the same.  That’s because both environments interpret the results differently.  Remember, you’re not retrieving two-dimensional row/column data like with a SQL query.  You’re retrieving multi-dimensional data!

If you take a closer look at the query that we’ve produced above, it’s similar to this:

SELECT something ON COLUMNS,
    something_else ON ROWS
FROM [Adventure Works]
That query is selecting data on two axes: COLUMNS and ROWS.  But in fact, MDX supports up to 128 axes.  However, the client tools that we are using here are not able to visualize that kind of cellset (as the result set of an MDX query is also called).
 
Okay, enough about our dataset.  We’ve got the data, let’s put it on the report!
 

Displaying The Result Set

As a reference, these are the fields available in our dataset:

Fields available in OLAP dataset

Without going into too much detail – there’s no difference compared to reporting off a relational database – I’ve set up a table with three grouping levels on the rows.  I’ve also added some makeup like background colors and font modifications.

As shown in following screenshot, the highest-level group is Country, followed by State_Province and City to conclude, just as specified in the requirements mentioned at the start of this chapter.

Table with three groupings defined

Rendering the report in preview gives us something like this:

Report without any numeric formatting applied

What is still missing at this point is decent formatting for those numbers!  And here’s where we can take advantage of the fact that we’re retrieving data from an OLAP cube.  A cube developer has the possibility to define the format for the measures in the cube itself.  Doing that ensures that the same formatting is applied no matter what OLAP client tool is used.  Any client that supports this way of formatting will show the numbers using the same format.

As you’ve seen in that last screenshot, there’s no formatting applied at all.  Does this mean that there was no format defined in the cube?  Let’s find out!

A Little Walk Into The Analysis Project

We are going to open up the Analysis Services project that contains the cube definition.  If you don’t have any experience with SSAS, don’t worry!  We will just have a look at a couple of properties and that’s it, plus I’ll explain each step as needed.  In case you’ve forgotten where the sources are located, this is the default location: C:\Program Files\Microsoft SQL Server\100\Tools\Samples\AdventureWorks Analysis Services Project\.  I’m opening the project located under the \enterprise subfolder by double-clicking the Adventure Works.sln file.

Once the project is loaded into the BIDS, locate and open the Adventure Works.cube in the Solution Explorer.  You can find it in the Cubes folder of the Adventure Works DW project.

By default it will open the cube Design showing the first page called Cube Structure.  At the top-left, we’ve got the Measures pane.  The measures are shown in measure groups.  Open the group called Reseller Sales.  Now locate the measure called Reseller Sales Amount and select it.

Cube in Design with Reseller Sales Amount selected

Now that we’ve selected one of the measures that we are retrieving in our report, have a look at the Properties window.  In case it’s not open yet you can right-click the measure and select Properties.  The property that we’re interested in is called FormatString.

Properties of the Reseller Sales Amount measure showing Currency as format string

The cube developer has specified that this measure should be shown as being a Currency.

Now that you’re in the cube, have a look at the properties for our other measure, the Reseller Order Quantity.  This one is being formatted as #,#.

The FormattedValue Field Property

So why are we not seeing those formats in our report?  Because by default they are not applied in an SSRS report!  When dragging fields from the Report Data window onto the design area, what the BIDS is retrieving is the Value property of the field.  However, there’s also a property called FormattedValue.

(You may want to make a copy of your report before applying the following changes.)

Now, change the six table cells that are showing the numbers (so including the ones showing the totals) to retrieve the FormattedValue property instead of the Value property.  The expression for the totals of the Reseller Sales Amount looks like this:

=Sum(Fields!Reseller_Sales_Amount.FormattedValue)

Once you’ve done that, have a look at the Preview:

Report Preview showing no numbers after retrieving the FormattedValue property

That doesn’t look right, does it?  We’ve lost our numbers!

Now hit the Refresh button: Refresh button in Report Preview

This time we’ve got some numbers:

Report Preview showing formatted numbers, and errors!

But we’ve also got some errors for free!  Looking at the Output window we get some extra details on the reason for the error.  Here’s one of them:

[rsAggregateOfNonNumericData] The Value expression for the textrun ‘Reseller_Order_Quantity1.Paragraphs[0].TextRuns[0]’ uses a numeric aggregate function on data that is not numeric.  Numeric aggregate functions (Sum, Avg, StDev, Var, StDevP, and VarP) can only aggregate numeric data.

In short, what it says is that our data is not numeric.  And this poses an issue when it tries to apply the SUM() aggregate function.  Right, as our data now contains formatting, it became a string instead of a number, and strings can’t be added together using SUM().

So that’s not a good way to apply the formatting, not in this case anyway.  Luckily there’s another method to do that.

But first, undo those last changes and replace the FormattedValue with the Value property.

(Or switch back to the original report if you took a copy earlier.)

The Cell Properties

What exactly is our MDX query doing?  I’m taking a closer look at it by taking it from the Dataset Properties window and pasting it into a MDX query window in the Management Studio:

SELECT
NON EMPTY { [Measures].[Reseller Sales Amount], [Measures].[Reseller Order Quantity] }
ON COLUMNS,
NON EMPTY { ([Geography].[Geography].[Postal Code].ALLMEMBERS ) }
DIMENSION PROPERTIES MEMBER_CAPTION, MEMBER_UNIQUE_NAME
ON ROWS
FROM [Adventure Works]
CELL PROPERTIES VALUE, BACK_COLOR, FORE_COLOR, FORMATTED_VALUE,
FORMAT_STRING, FONT_NAME, FONT_SIZE, FONT_FLAGS

Besides retrieving the requested measures and dimension attributes, it’s retrieving several Cell Properties, including FORMATTED_VALUE and FORMAT_STRING.  I believe that the first one rings a bell by now.  What we’re going to do is to retrieve the second one and apply it as Format property for our numeric table cells.

In the report’s Design, select one of the table cells containing a number.  In the Properties window, one of the properties is called Format.  Click to select it, then in the dropdown choose Expression….  For each of the six numeric cells, create an expression similar to the following:

=Fields!Reseller_Order_Quantity("FORMAT_STRING")

The example above tells the BIDS to retrieve the FORMAT_STRING cell property from the Reseller_Order_Quantity field.

Tip: you don’t need to open up the Expression builder for each of the six cells.  You can just copy/paste the string from the Format field.  Just ensure that you’re retrieving the format from the same field as the one that the cell is displaying.

Now let’s have a look at the Preview again:

Format is working for the quantity amounts but not for Currency!

Hmm,  the quantities are fine now, but the currencies are not!  So, let’s try out yet another method for those cells.

For the three cells containing a currency measure, remove the Format property – it’s not working anyway!

Next, change the expression that’s retrieving the Value property to something similar as this one:

=Format(Sum(Fields!Reseller_Sales_Amount.Value),
    Fields!Reseller_Sales_Amount("FORMAT_STRING"))

This expression applies the value of the FORMAT_STRING property using the Format() function.  In this particular case it’s the expression used to produce the Reseller Sales Amount total.

Having modified all three currency cells, here’s another Preview look:

Both Currency and regular numeric cells are showing formatted values!

That certainly looks better doesn’t it?!

Okay, to conclude, let’s activate drilldown by setting the subgroup levels to a collapsed state by default.

I will not go into full detail on this.  To start, make sure that the cells that are going to contain the +/- toggle have gotten a decent name, such as txtCountry for the cell that shows the Country name.  Then edit the properties of the subgroups by setting Visibility to Hide.  Also, activate the Display can be toggled by this report item checkbox and select the textbox showing the label one level higher.  Shown below is how to configure the group on State_Province.

Group Properties showing how to activate drilldown

 

Let’s have another look at the report Preview:

Fully working drilldown report

By default all nodes were collapsed.  I’ve expanded a couple of them just to show that it’s all working.

The InitialToggleState Property

Okay, I will not let you go just yet.  To really conclude I’ll let you in on a little feature related to the drilldown.  Open up the group properties for the State_Province group and set the initial visibility to Show (leave the “Display can be toggled by this report item” checked!).  Then checkout Preview:

Visibility toggle is broken!

Wow, that’s weird, the country level is expanded and yet there’s a plus icon in front of the country’s name.  Clicking it will collapse the states and change the icon to minus.  If that isn’t mixed up then I don’t know what is!

Well, the solution to this problem is simple.  Select the textbox showing the country name and locate the InitialToggleState property.  By default this is set to False, which means collapsed or in other words, False shows the plus icon.  Change it to True and now your initial state icon will be a minus!

Conclusion

With this article I believe to have shown you how to get started with reporting off an OLAP cube while throwing in a couple of tips in the process.

Have a look at another article that I wrote earlier, it explains an issue which you may run into when taking OLAP reporting a step further: SSRS and MDX: Detecting Missing Fields

Happy Reporting!

Valentino.

References

BOL 2008: The Basic MDX Query

BOL 2008: Using Cell Properties (MDX)

MDX: Retrieving Cell Properties by Greg Galloway

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If you’ve got some experience building Data Flows in your Integration Services packages, you probably already know that SSIS has its own representation of the different data types.  The names of these data types start with DT_, followed by the actual type such as BOOL for boolean and STR for string.

Some data types you use every day and others only once in a while.  So some you already know by heart and others you don’t.  A nice example of one that I certainly don’t need to look up anymore is the following cast as used in a Derived Column Transformation: (DT_STR, 100, 1252)YourField.  It converts YourField to a string field of length 100 using the ANSI – Latin 1 code page.

But the reason for this post are the other types, the ones not used daily.  Because each time that I need info on one of those, I find myself ploughing through several BOL pages before finding that page of which I know it exists but where, oh where?!

So, on the following Books Online page you can find a list of all SSIS data types and their definition: Integration Services Data Types

And at the bottom of that same page there’s an interesting table showing the mapping between the SSIS types and those of several RDBMS, including SQL Server of course.

Another interesting page is this one: Working with Data Types in the Data Flow

The bottom half of this page contains a mapping table between the SSIS data types and their corresponding managed type in .NET.  This is especially useful when you’re doing some custom development like a custom data flow component.  But you don’t need to take it that far, even when you’re just using the built-in Script Component task for some complex data conversions, you’ll find this useful.  After all, you’re also programming in a managed .NET language in that component.

Okay, that’s it for now, hopefully this will save you some time searching for those reference pages.  I already know that I’ll be coming back to this post once in a while :-)

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If you’re interested in seeing the next Service Pack for SQL Server 2008 released, vote for it at this Microsoft Connect page!  Now that the release date for R2 has been announced, hopefully the next one is for SQL 2008 Service Pack 2.

If you’re still on 2005 and thus more interested in an SP4 for that version, it has also been posted at Connect.

How did I find out?  Through the following blog posts at SSQA.NET:

SQL Server 2008 SP2

SQL Server 2005 SP4

Update (27 Feb 2010):

SQL Server 2008 SP2 is scheduled for Q3 2010.

SQL Server 2005 SP4 is scheduled for Q4 2010.

See this post on the Microsoft SQL Server Release Services blog for details.

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What?

image

Service Broker provides queuing and reliable messaging for SQL Server. Service Broker is used both for applications that use a single SQL Server instance and applications that distribute work across multiple instances.

Within a single SQL Server instance, Service Broker provides a robust asynchronous programming model. Database applications typically use asynchronous programming to shorten interactive response time and increase overall application throughput.

Service Broker also provides reliable messaging between SQL Server instances. Service Broker helps developers compose applications from independent, self-contained components called services. Applications that require the functionality exposed in these services use messages to interact with the services. Service Broker uses TCP/IP to exchange messages between instances. Service Broker includes features to help prevent unauthorized access from the network and to encrypt messages sent over the network.

(The above was quoted from the BOL.)

Who?

Dr. Nico Jacobs, PhD in Data Mining, trainer/consultant at U2U focusing on SQL Server/BI.

When?

February 11, 2010.

Where?

Avenade, Vilvoorde.

Register here: http://sqlug.be/nextevent/

More info at the SQLUG site.

See you there!

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