Question

I am building an app which requires users to fill out a questionnaire on a daily basis. The questions are always the same. Essentially it is a diary system and ‘entries’ are made on a daily basis (each entry is the set of answers to the 5 questions on a particular date by a particular user).

My question is this:

What is the best way to orgabise this in terms of database schematics? I was thinking of having two tables:

Users:
username(pk)
password
.
.
diaryNo

Entries:
date(pk)
diaryNo(pk)
Qu1
Qu2
...

My problem with this is that the entry table will store entries for all users. A particulat entry can be mapped to a user by linking diaryNo. Obviously after a while, the entries table will become massive and sql performance will decrease.

This must be a common problem- are there any workarounds? better ideas for implementation?

Answer 1

An index on either Entries (diaryNo) or Entries (diaryNo,date), especially if you are selecting Entries based on diaryNo frequently. i.e. diaryNo=? appears in most of the select queries.