LIMIT then RAND rather than RAND then LIMIT

Posted by Larry on Stack Overflow See other posts from Stack Overflow or by Larry
Published on 2010-04-15T18:44:48Z Indexed on 2010/04/15 19:53 UTC
Read the original article Hit count: 532

Filed under:

mysql

|

rand

|

limit

I'm using full text search to pull rows.
I order the rows based on score (ORDER BY SCORE) , then of the top 20 rows (LIMIT 20), I want to rand (RAND) the result set.

So for any specific search term, I want to randomly show 5 of the top 20 results.

My workaround is code based- where I put the top 20 into an array then randomly select 5.

Is there sql way to do this?

© Stack Overflow or respective owner

Related posts about mysql

How to remove MySQL completely with config and library files on ubuntu 12.04 gnome 3.0

as seen on Ask Ubuntu - Search for 'Ask Ubuntu'
I tried everything till now: sudo apt-get remove mysql-server mysql-client mysql-common sudo apt-get purge mysql-server mysql-client mysql-common sudo apt-get autoremove and even more commands... But whenever I am trying to locate mysql. I get a no. of files related to mysql command: shell>>… >>> More
mysql: Cannot load from mysql.proc. The table is probably corrupted

as seen on Server Fault - Search for 'Server Fault'
Mysql was started: /usr/bin/mysqld_safe --datadir=/srv/mysql/myDB --log-error=/srv/mysql/logs/mysqld-myDB.log --pid-file=/srv/mysql/pids/mysqld-myDB.pid --user=mysql --socket=/srv/mysql/sockets/mysql-myDB.sock --port=3700 but when I'm trying to do something: ERROR 1548 (HY000) at line 1: Cannot… >>> More
Why is there a /etc/init.d/mysql file on this Slackware machine? How could it have gotten there?

as seen on Server Fault - Search for 'Server Fault'
A client of my IT-consulting service owns a web-development shop. He's been having problems with a Slackware 12.0 server running MySQL 5.0.67. The machine was set up by the client's sysadmin, who left on bad terms. My client no longer employs a sysadmin. As far as I can tell, the only copy of MySQL… >>> More
mysql: Bind on unix socket: Permission denied

as seen on Server Fault - Search for 'Server Fault'
Can't start mysql with: sudo /usr/bin/mysqld_safe --datadir=/srv/mysql/myDB --log-error=/srv/mysql/logs/mysqld-myDB.log --pid-file=/srv/mysql/pids/mysqld-myDB.pid --user=mysql --socket=/srv/mysql/sockets/mysql-myDB.sock --port=3700 120222 13:40:48 mysqld_safe Starting mysqld daemon with databases… >>> More
MySQL – Learning MySQL Online in 6 Hours – MySQL Fundamentals in 320 Minutes

as seen on SQL Authority - Search for 'SQL Authority'
MySQL is one of the most popular database language and I have been recently working with it a lot. Data have no barrier and every database have their own place. I have been working with MySQL for quite a while and just like SQL Server, I often find lots of people asking me if I have a tutorial which… >>> More

Related posts about rand

MySQL: LIMIT then RAND rather than RAND then LIMIT

as seen on Stack Overflow - Search for 'Stack Overflow'
I'm using full text search to pull rows. I order the rows based on score (ORDER BY SCORE) , then of the top 20 rows (LIMIT 20), I want to rand (RAND) the result set. So for any specific search term, I want to randomly show 5 of the top 20 results. My workaround is code based- where I put the top… >>> More
LIMIT then RAND rather than RAND then LIMIT

as seen on Stack Overflow - Search for 'Stack Overflow'
I'm using full text search to pull rows. I order the rows based on score (ORDER BY SCORE) , then of the top 20 rows (LIMIT 20), I want to rand (RAND) the result set. So for any specific search term, I want to randomly show 5 of the top 20 results. My workaround is code based- where I put the top… >>> More
PHP rand function (or not so rand)

as seen on Programmers - Search for 'Programmers'
I was testing PHP rand function to write on a image. Of course the output shows that it's not so random. The code I used: <?php header('Content-Type: image/png'); $lenght = 512; $im = imagecreatetruecolor($lenght, $lenght); $blue = imagecolorallocate($im, 0, 255, 255); for ($y = 0; $y < $lenght;… >>> More
Plotting points so that they do not overlap if they have the same co-ordinates

as seen on Stack Overflow - Search for 'Stack Overflow'
Hi everyone, I have a function that takes longitude and latitude and converts it to x and y to be plotted. The conversion to X and Y is working fine and that is not what I have the problem with. I want to ensure that two points are not plotted in the same place. In one set of results there are about… >>> More
problems with infinite loop

as seen on Stack Overflow - Search for 'Stack Overflow'
function addAds($n) { for ($i=0;$i<=$n;$i++) { while($row=mysql_fetch_array(mysql_query("SELECT * FROM users"))) { $aut[]=$row['name']; } $author=$aut[rand(0,mysql_num_rows(mysql_query("SELECT * FROM users")))]; $name="pavadinimas".rand(0,3600); $rnd=rand(0,1); if($rnd==0) { … >>> More