I worked on a task where I had to modify our NANT build file to MSBuild file and I had to all those changes in notepad.
Sometime I wonder why I never did googling for "UI editor for modifying the MSBuild file". It may not be very important finding but I thought to put it blog because I made a mistake by not doing even basic analysis work before starting a tedious work.
Friday, December 22, 2006
Microsoft Build Sidekick
Tuesday, December 12, 2006
Normalization - Where to Stop?
Why most designers don't go beyond the 3NF?
The First thing we learn in our DBMS Topics is Normalization. Whether you are a data modeler, DBA, or SQL developer, normalization is one of those topics we all learn. We learn this early either at work or during our formal IT degree.
But take a look at most production databases. The best you will find that the database has been implemented using Third normal form (3NF). Very few databases reflect higher normal forms, such as Boyce-Codd normal form (BCNF), the Fourth normal form (4NF), and the Fifth normal form (5NF). So, why don't most database designers go beyond the 3NF?
If you want to know what these normal forms are, they can be found in my previous post for your reference.
How far should you go with normalization?
To be sure, each progressive step may impact upon overall performance. I have seen normalization taken to absurd lengths. In one of the recent discussion one person came out with the idea of different financial document types. As though the world of accounting is going to change. I had to remind him that Accounting is just the recording of historical events :)
A while ago I was reading an article and there the author mentioned about the normalization. Over a period of time I learnt to ask few questions before I decide how much normalization is required.
1. What is the nature of the system. Is it an OLTP or OLAP system?
2. What is the nature of DB Query. Are they mostly Insert or Retrieve?
3. For Part of DB where the inserts are more, its better to have the Data in 3rd normal form.
4. For system where Retrieve operation is more than Inserts, 2nd Normal form is the best.
Where you draw the line in the sand is ultimately up to you, but you will be better equipped to draw it with a sound understanding of the various normal forms and the risks of not going far enough.
Until Next Time... :)
The First thing we learn in our DBMS Topics is Normalization. Whether you are a data modeler, DBA, or SQL developer, normalization is one of those topics we all learn. We learn this early either at work or during our formal IT degree.
But take a look at most production databases. The best you will find that the database has been implemented using Third normal form (3NF). Very few databases reflect higher normal forms, such as Boyce-Codd normal form (BCNF), the Fourth normal form (4NF), and the Fifth normal form (5NF). So, why don't most database designers go beyond the 3NF?
If you want to know what these normal forms are, they can be found in my previous post for your reference.
How far should you go with normalization?
To be sure, each progressive step may impact upon overall performance. I have seen normalization taken to absurd lengths. In one of the recent discussion one person came out with the idea of different financial document types. As though the world of accounting is going to change. I had to remind him that Accounting is just the recording of historical events :)
A while ago I was reading an article and there the author mentioned about the normalization. Over a period of time I learnt to ask few questions before I decide how much normalization is required.
1. What is the nature of the system. Is it an OLTP or OLAP system?
2. What is the nature of DB Query. Are they mostly Insert or Retrieve?
3. For Part of DB where the inserts are more, its better to have the Data in 3rd normal form.
4. For system where Retrieve operation is more than Inserts, 2nd Normal form is the best.
Where you draw the line in the sand is ultimately up to you, but you will be better equipped to draw it with a sound understanding of the various normal forms and the risks of not going far enough.
Until Next Time... :)
Database Normalization
I was talking to a developer a while ago and when I started talking about database normalization the other person was kind of lost in a vaccum. I was wondering what happened, but then realized that he does not know much about the normalization and he finds it kind of boring. Boring because all the text books give very lengthy explanation of normalization and most of the times they are boring to read :)
Being a Developer It's important to understand the differences between 3NF, BCNF, 4NF, and 5NF along with other normal forms. Here are concise definitions of each normal form.
First normal form (1NF)
Each table must have a primary key, i.e., a minimal set of attributes that can uniquely identify a record. Eliminate repeating groups (categories of data that would seem to be required a different number of times on different records) by defining keyed and non-keyed attributes appropriately. Atomicity: Each attribute must contain a single value, not a set of values.
Second normal form (2NF)
The database must meet all the requirements of the 1NF. In addition to that, if a table has a composite key, all attributes must be related to the whole key. And, data that is redundantly duplicated across multiple rows of a table is moved out to a separate table.
Third normal form (3NF)
In Addition to all the requirements for 2NF, The data stored in a table must be dependent only on the primary key and not on any other field in the table. Any field that is dependent not only on the primary key but also on another field is moved out to a separate table.
Boyce-Codd normal form (BCNF)
There must be no non-trivial functional dependencies of attributes on something other than a superset of a candidate key (called a superkey).
Fourth normal form (4NF)
There must be no non-trivial multi-valued dependencies of attribute sets on something other than a superset of a candidate key. A table is said to be in 4NF if and only if it is in the BCNF and multi-valued dependencies are functional dependencies. The 4NF removes unwanted data structures: multi-valued dependencies.
Fifth normal form (5NF)
There must be no non-trivial join dependencies that do not follow from the key constraints. A table is said to be in the 5NF if and only if it is in 4NF and every join dependency in it is implied by the candidate keys.
Happy Reading :)
Until Next time... :)
Being a Developer It's important to understand the differences between 3NF, BCNF, 4NF, and 5NF along with other normal forms. Here are concise definitions of each normal form.
First normal form (1NF)
Each table must have a primary key, i.e., a minimal set of attributes that can uniquely identify a record. Eliminate repeating groups (categories of data that would seem to be required a different number of times on different records) by defining keyed and non-keyed attributes appropriately. Atomicity: Each attribute must contain a single value, not a set of values.
Second normal form (2NF)
The database must meet all the requirements of the 1NF. In addition to that, if a table has a composite key, all attributes must be related to the whole key. And, data that is redundantly duplicated across multiple rows of a table is moved out to a separate table.
Third normal form (3NF)
In Addition to all the requirements for 2NF, The data stored in a table must be dependent only on the primary key and not on any other field in the table. Any field that is dependent not only on the primary key but also on another field is moved out to a separate table.
Boyce-Codd normal form (BCNF)
There must be no non-trivial functional dependencies of attributes on something other than a superset of a candidate key (called a superkey).
Fourth normal form (4NF)
There must be no non-trivial multi-valued dependencies of attribute sets on something other than a superset of a candidate key. A table is said to be in 4NF if and only if it is in the BCNF and multi-valued dependencies are functional dependencies. The 4NF removes unwanted data structures: multi-valued dependencies.
Fifth normal form (5NF)
There must be no non-trivial join dependencies that do not follow from the key constraints. A table is said to be in the 5NF if and only if it is in 4NF and every join dependency in it is implied by the candidate keys.
Happy Reading :)
Until Next time... :)
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