Re: Database design for multiple choice questionnaire results?

[timb]

For my much smaller surveys, multiple-choice questions get just one tinyint column with possible values of 1, 2, 3, etc. up to the number of answers available for that question. This assumes that the respondent may only select one answer for each question. Only questions where the respondent is allowed to select more than one answer have a column for each answer.

If even half of your 600 survey questions are single answer only that would reduce the number of columns from 3,000 to 1,800 and allow indexing of the single answer columns (300 indexes instead of 1,500).