计算两个表中匹配的记录

Question

I have two tables. "question_answers" having columns question and answer . "question_attempts" having questionid and responsesummary .

Example : question =4 having 5 records from "question_answers". Same questionid in the "question_attempts" and find and get the count of matching records count in "question_attempts"

"question_answers" "question_attempts"

Answer 1

It would be much easier if i could have a sample of those tables here, but give this a try

SELECT 
    answers.id AS 'answer id',
    count(attempts.id) AS 'number of attempts'    
FROM
    question_attempts AS attempts
JOIN
    question_answers AS answers ON answers.answer = attempts.responsessummary
WHERE 
    question_answers.question = 1
GROUP BY 
    answers.id;

if it works correctly you should receive a table of answer ids with the number of attempts for that answer.

BUT you need to have exact match in those two fields. answer from question_attempts and responsessummary from question_answers.

if it not possible the workaround is to use LIKE clause :

SELECT 
    answers.id AS 'answer id',
    count(attempts.id) AS 'number of attempts'    
FROM
    question_attempts AS attempts
JOIN
    question_answers AS answers ON answers.answer 
        LIKE CONCAT('%', attempts.responsessummary , '%')
WHERE 
    question_answers.question = 1
GROUP BY 
    answers.id;