582 reputation
38
bio website
location
age
visits member for 3 years, 5 months
seen yesterday

Retired. Once a programmer, then a DBA.


2d
revised subtypes wiki excerpt
added 63 characters in body
2d
revised subtypes wiki description
added 929 characters in body
2d
wiki created subtypes description
2d
wiki created subtypes excerpt
2d
suggested suggested edit on subtypes tag wiki
2d
suggested suggested edit on subtypes tag wiki excerpt
2d
awarded  Organizer
2d
revised Relationships between subtypes of an entity
Added new tag, subtypes
2d
suggested suggested edit on Relationships between subtypes of an entity
Jul
26
comment Database Design for classifieds site
WRT subcategories, it sounds like they are like classes and subclasses in OOP. If so, check out the answers to This question.
Jul
13
revised Entity Relationship Model - double one to many
added 181 characters in body
Jul
13
comment Data modeling with many attributes where few apply to each record
Option 1 is convenient when you want to use data that pertains to all rows, regardless of subclass. The width of the table adds unnecessary bulk, slowing things down. But it's easy. See my Option 4 answer for an alternative.
Jul
12
comment Entity Relationship Model - double one to many
What normal form does LEAD violate?
Jul
12
answered Entity Relationship Model - double one to many
Jul
12
comment Datatype for different categories in a database
I agree with Sebas. When three tables all have the same columns, the chances are the data will be more useful if it's all stored in one table. In your case, there shouldn't be enough rows to warrant splitting the tables for physical reasons.
Jul
12
comment Data modeling with many attributes where few apply to each record
I haven't built a MySQL database, but I can't see where the technique would require anything that MySQL doesn't offer. It's just a collection of Tables, rows, columns, primary keys, and foreign keys.
Jul
11
answered Data modeling with many attributes where few apply to each record
Jul
7
comment Relational Database design best practice
Shared primary key looks weird to me as well. But it has a lot to recommend it, even in the real world.
Jul
5
revised How can I improve my table design for different types of an entity?
added 3 characters in body
Jul
4
comment Personal and Global messaging database design
It would seem that the relationship between persons and messages is really many-to-many. If so, you should make that clearer in your question.