I want to make a list of 10 random rows in $Tt. Because some old topics maybe interested for somebody, example in a poem/ story forum, But I don't know how to query MySql. I don't want to run 10 queries at once. Can you help me? Thank you very much.

I think, you don't have to run 10 queries, but just make a "random" order.

is probably about what you need...

Thanks.
But can 'order by rand()' take several seconds? Because it sort all rows then choose only 10 rows

SELECT * FROM $Tt WHERE (ABS(CAST((BINARY_CHECKSUM(*)*RAND()) as int)) %100) < 10