Hello,
What are your top 2 rules for database normalization?
Thanks
Database Normalization
3 years ago
3 years ago
#1
3 years ago
#2
Ok,
How about how many columns in a table?
Maximun
How about how many columns in a table?
Maximun
3 years ago
#3
Hi Dan,
It's been a while since my last post, and have noticed no one here has tried to answer your query :(
For me, there are 2 main rules for normalisation.
- First Normal Form (1NF) is to keep each piece of information in its own box, avoiding any mixing of data. Avoid repeatpng groups of data, each column should also contain data that is relevant to that column.
- Second Normal Form (2NF) Make sure related info is kept together, so if one thing changes, it doesn't cause confusion elsewhere. Eliminate partial dependencies; this means that each non-key column should be fully dependent on the entire primary key, not just part of it.
Also, as a general rule, max columns - no more than 20 to 30 as long as they keep to the above normal form rules.
Cheers,
Si
It's been a while since my last post, and have noticed no one here has tried to answer your query :(
For me, there are 2 main rules for normalisation.
- First Normal Form (1NF) is to keep each piece of information in its own box, avoiding any mixing of data. Avoid repeatpng groups of data, each column should also contain data that is relevant to that column.
- Second Normal Form (2NF) Make sure related info is kept together, so if one thing changes, it doesn't cause confusion elsewhere. Eliminate partial dependencies; this means that each non-key column should be fully dependent on the entire primary key, not just part of it.
Also, as a general rule, max columns - no more than 20 to 30 as long as they keep to the above normal form rules.
Cheers,
Si