Survey access_code not guaranteed to be unique about surveyor

[yoon]

Since one may generate surveys (and corresponding fixtures) at a very different time than importing them, looking up surveys in the database won't help the parser generate a unique access_code. Additionally, there aren't many use cases for having surveys with the same title, as users would be unable to differentiate them. If a use case is found, we'll rely on the developer to assign unique access codes with the survey method hash in the dsl.

We'll add unique index on access_code in the surveys table, and a validator to the Rails model should someone create Surveys through an admin index.

[yoon]

contrain surveys to have unique access_codes. closed by 572faf219240aeebcd15082bc97031f18da0117d, #42

[jakewendt]

Thank you for making the mods. I can clean up some of my code now. However, the indexes added for access_codes in surveys and response_sets is missing the ":unique => true". Without it, the db won't enforce uniqueness, although the model will.

[yoon]

add unique indicies. closed by 660dc3f