如何用 mysql 按概率随机查询

可以试试 select * from products,products_description where products.master_categories_id=67 and products.products_id=products_description.products_id order by rand(10) limit 20

这是随机抽取前20条，主要是用到 order by rand()

select * from test_00

union all

select * from test_01

union all

select * from test_02

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