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MySql Query to get certain number of values from limit and order by rand()

In below SQL query I need 25 rows containing product = ‘y’ and 25 rows having product = ‘n’. Product is a column having Y/N value only. In limit of random 50 rows I need 25 rows from each values.

SELECT qno 
FROM `wp_question_bank` 
where brand='XYZ' 
and department='DOMESTIC' 
and product = 'y' 
and priority = 'p1' 
ORDER BY RAND() limit 50

Kindly assist. I have tried Union but it didn’t work.

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Answer

Simply use UNION for each product type:

(SELECT qno
FROM `wp_question_bank`
WHERE brand='XYZ' AND department='DOMESTIC' AND product = 'y' AND priority = 'p1'
ORDER BY RAND()
LIMIT 25)

UNION ALL

(SELECT qno
FROM `wp_question_bank`
WHERE brand='XYZ' AND department='DOMESTIC' AND product = 'n' AND priority = 'p1'
ORDER BY RAND()
LIMIT 25)

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