user_default_avatar table, but the result of the query is always greater than 500 instead of floating around 500?
select *
from user_default_avatar
order by rand()
limit 100;
user_default_avatar table, but the result of the query is always greater than 500 instead of floating around 500?
select *
from user_default_avatar
order by rand()
limit 100;well, in fact, it has something to do with the id distribution density of the data. If the later number distribution density is large, it will result in a number greater than 1 answer 2.
this algorithm is not more efficient than the one you have been scolded. Aren't you afraid of being scolded again?
both methods need to calculate a random number for each row, and your new statement may not be as fast as before.
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