Friday, July 30, 2010

MMC cannot open -- in Citrix

Today I had a problem with our citrix server, where in the Management Console was not opening as usual when I try to open any of the below processes. Citrix Access Management console, Event Viewer, Manage Server, Administrative tools etc.

but I could access the event viewer from another machine. Here is what the event viewer error message says.

Here are the steps I have been advised to follow by Aaron Mountford (gen-i consultant) to resolve this.

I have registered the two dlls as follows.

Click Start, click Run, type regsvr32 Msxml3.dll, and then click OK
Click Start, click Run, type regsvr32 %systemroot%\system32\inetsrv\wamreg.dll, and then click OK.

Thursday, July 29, 2010

Convert a date to show AM/PM in SQL

Today I was working on a date column -- create_date. I wanted to show whether the row was created in the morning or in the evening i.e., AM/PM

This is what I did to achieve this.

SELECT rn_create_date, SUBSTRING(CONVERT(varchar(20), Rn_create_date, 22), 18, 3) AS Expr1
FROM tablename;

Here is the link to the BIDN blog where I have posted
If we are used to the Query Analyser of SQL Server 2000, we might find it frustrating that the query window does not automatically come up when you start SSMS.

You have to either press Ctrl+N or Click on New Query to start it up.

Here is a way to start up the New Query window automatically.

Click on Tools-- Options click on the + to exapnd environment and click on General.

The following screen comes up.

Click on the drop down beside start up and choose ' Open Object Exlpoer and New query'.

Click Ok. Next time when you open SSMS the query window will automatically be opened for you.

Here is link to the blog I posted in my BIDN blog.

Friday, July 23, 2010

Hiding your folders using command prompt

To hide your folders using the command prompt, click start -- run -- Type cmd and press enter

The commoan screen appear.

Do the following:

  • To hide, d:/>attrib +h +s +r

  • To revert d:/>attrib -h -s -r

The folder ill be still hidden even if you set 'show all hidden files' under folder view options

Make sure you keep a note of your fodler name otherwise you cannot unhide it.

Thursday, July 22, 2010

Star Schema vs. Snowflake Schema

Star Schema

• Start schema is simpler and hence good to use for small data warehouses. The rules that apply here are as follows:
• Each dimension is represented by a single dimension table
• Each dimensional table is related to or linked to a fact table.
• The relation is merely a master and detail relationship with Primary key being the dimension and reference key in the fact table.
• When there are 5 or more dimensions referring to one fact table it appears like a star and hence the name star schema
• In terms of ease of use you need less complex queries and easy to understand
• This design has redundant data and hence hard to maintain and change.
• Lesser query execution time due to lesser number of queries

Snowflake Schema
• Snowflake schema starts like a star schema and more complex and hence it is good to use the snow flake schema for large data warehouses. The rules that apply here are as follows:
• Each dimension is represented by a two or more dimension tables
• Each dimensional table is not directly related to fact table
• Here the tables that describe the dimensions are normalised.
• In terms of ease of use you have to use more complex queries
• There is no redundancy and easy to maintain and change
• More query execution time because of more foreign keys

Friday, July 16, 2010

Make movies online

Today I came across this site where you can make movies on the web. Here is the link.

You can start creating movies just by typing your text.

Free Databases and Data Visualisations course for kids Weeks 9 to 11 update

It has been quite a while since I have posted about the free databases and data visualisation classes for 9 to 14 year old kids.  So here I...