Question

i am currently working on a project where i have ‘units’ that will have three different ‘phases’ and three ‘steps’ to each ‘phase’. I am having trouble designing the layout of my database whereby i dont not know whether to put it all in one table or multiple tables.

for instance:

table 1: unit_id, unit_category, unit_name, unit_phase, unit_step

or:

table 1: unit_id, unit_category, unit_name

table 2: phase_id, phase_name, unit_id

table 3: step_id, step_name, unit_id

…

is it easier to constantly update fields in a row, or is it better to place the ‘units’ id in other tables??

(also, each phase has the exact same steps)

to clarify:
each unit goes through 5 different phases. within each phase is 3 steps. once the unit has gone through all of the phases, it returns to a rest state. the user is the one who starts the process.

Answer 1

You should loot at database normal forms rules. That will help to design your tables.

Look at:

• Database Normalization Basics
• Rules of DB normalization
• DB normalization

Rules:

• Eliminate duplicative columns from the same table.
• Create separate tables for each group of related data and identify each row with a unique column or set of columns (the primary key).
• Remove subsets of data that apply to multiple rows of a table and place them in separate tables.
• Create relationships between these new tables and their predecessors through the use of foreign keys.
• Remove columns that are not dependent upon the primary key.