Dear all, A table "book" looks like this:
"page" "content" -------------- 1 abc 1 de 2 fgh 3 ijk 3 lmn 3 opq ... 210 z I need a query to randomly select 90% of all pages and their corresponding contents. I have written the following querys. But I have problems to combine them into a single one. (I use mysql.) // Randomly select 40 pages of the book. Query1: SELECT DISTINCT page FROM tbl ORDER BY RAND() LIMIT 40; // Count the total pages of the book. But how to use this value in the LIMIT clause in the above query to indicate 90% of all pages? Query2: SELECT COUNT(DISTINCT page) FROM book; // How to embed/alias Query1 in Query3? Query3: SELECT * FROM book WHERE page IN Q1; Thanks a lot.
