Poor Man's SQL Pivot. List Questions as Columns and Answers per User in one row
Current query:
SELECT order_id AS OrderNumber, ordName, ordLastName, question, answer
FROM cart_survey
JOIN orders
ON cart_survey.order_id=orders.ordID
JOIN survey_answers
ON survey_answers.id=cart_survey.answer_id
JOIN survey_questions
ON survey_questions.id=cart_survey.question_id
Results:
OrderNumber ordName ordLastName question answer 8591 Larry Marshburn Type of Surgery: Colostomy 8591 Larry Marshburn Month of Surgery: 2 8591 Larry Marshburn Year of surgery: 2010 8591 Larry Marshburn Current Ostomy System Brand: ConvaTec 8591 Larry Marshburn Degree of Satisfaction: Somewhat Satisfied 8593 Melvin Belcher Type of Surgery: Urostomy 8593 Melvin Belcher Month of Surgery: 9 8593 Melvin Belcher Year of surgery: 2010 8593 Melvin Belcher Current Ostomy System Brand: ConvaTec 8593 Melvin Belcher Degree of Satisfaction: Very Satisfied
How do I properly query the tables to pull results that will look like this? Name and Lastname on a single line and questions for columns and answers for each column.
Desired Results
OrderNumber ordName ordLastName "Type of Surgery" "Month of Surgery" "Year of Surgery" etc. 8591 Larry Marshbourn Colostomy 2 2010 8593 Melvin Belcher Urostomy 9 2010
Solution 1:
The posted answers work but are clumsy and slow. You can do what I call parallel aggregation:
SELECT
ID,
SUM(case when question_id = 1 then 1 else 0 end) as sum1,
SUM(case when question_id = 2 then 1 else 0 end) as sum2,
SUM(case when question_id = 3 then 1 else 0 end) as sum3
GROUP BY ID
This will do one pass over the table instead of three and is very short. It is not a complete walk-through but you can surely adapt the concept to your needs.
Solution 2:
This is called a pivot, where information in rows is used to determine the list of columns. This sort of query requires dynamically-computed SQL if done entirely in a query, and is usually better suited to client-side formatting instead (many tools call it a pivot or cross-tab query, SSRS calls it a matrix query).