sql - Mysql query different random conditions -


i need have random question question bank. have table, question, column: questiontype. need random questions table depending on request of user.

for example, chooses, questiontype: ['identification', 'multiple choice'] , number of questions per questiontype: ['10', '20'].

so need query random 10 questions column questiontype value identification , 20 random questions column questiontype value multiple choice.

i have sql statement:

select question question questiontype = 'identification' order rand() limit 10;

so how can add condition:

questiontype = 'multiple choice' order rand() limit 20

can please me? thanks!

try this:

select question  ( (select question question questiontype = 'identification' order rand() limit 10) union (select question question questiontype = 'multiple choice' order rand() limit 20) ) t order rand()

see demo in sql fiddle.


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