I have an interesting conundrum which I believe can be solved in purely SQL. I have tables similar to the following:
responses: user_id | question_id | body ---------------------------- 1 | 1 | Yes 2 | 1 | Yes 1 | 2 | Yes 2 | 2 | No 1 | 3 | No 2 | 3 | No questions: id | body ------------------------- 1 | Do you like apples? 2 | Do you like oranges? 3 | Do you like carrots?
and I would like to get the following output
user_id | Do you like apples? | Do you like oranges? | Do you like carrots? --------------------------------------------------------------------------- 1 | Yes | Yes | No 2 | Yes | No | No
I don't know how many questions there will be, and they will be dynamic, so I can't just code for every question. I am using PostgreSQL and I believe this is called transposition, but I can't seem to find anything that says the standard way of doing this in SQL. I remember doing this in my database class back in college, but it was in MySQL and I honestly don't remember how we did it.
I'm assuming it will be a combination of joins and a GROUP BY statement, but I can't even figure out how to start.
Anybody know how to do this? Thanks very much!
Edit 1: I found some information about using a crosstab which seems to be what I want, but I'm having trouble making sense of it. Links to better articles would be greatly appreciated!
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