I used to label columns in my databases like this: user_id user_name user_password_hash To avoid conflicts when joining two tables, but then I learnt some more on how to alias tables, and I stopped ...
I am developing this application with an Oracle database. I haven't been documenting the data model, but now an auditor wants to have an entity relationship diagram of my database. There are many ...
Consider the following ternary relationship: Suppose that all entities have only two attributes (PK and Name). Here are the tables I derived (5 tables): Sector ------------------------- ...
I've been trying to figure this out for a while. Let's say you have a person, for example. An attribute of a person is his or her social security number, right? But a person also has a social ...
How can I import the contents of an Oracle database into Visio to create an Entity Relationship Diagram?
I have an Oracle database, and I would like to create an ERD in Visio 2007 Pro. I have so far looked at DBMS_METADATA.GET_DDL commands to generate ddl. I know that I can import an Access DB into ...
How much the decision to use ternary or binary relationship influences the accuracy of the model with regards to a given business model?
The question title is very long, so here's a little bit of context to (try to) make it clear. I asked a question regarding ternary relationship. The question was Ternary relationship: what's the ...
Consider the following ERD: Suppose that all entities only have two attributes: a PK plus a name/number. I want to convert that ERD to tables. Is it needed 4 tables (1 for each relationship ...
I am using mysql as my backend database. Here is the use case; A HolidayPackage is configured with some default offerings. These default offerings can be up/downgraded based on the options provided. ...