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How to randomly order or select rows in a MySQL query

October 28th, 2008  |  by Knix  |  published in mysql

I was looking for a way to order the rows randomly in a MySQL query and the solution was not easy for me to come by. I am posting the solution here in hopes of helping others.

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SELECT *
FROM my_table
ORDER BY RAND()

RAND() returns a random floating-point value but functions to randomly order the selection [...]

How to convert MySQL timestamp to PHP date type

October 5th, 2008  |  by Knix  |  published in mysql, php

Let’s say you have the following PHP code that extracts the date from the times table in your MySQL database. The date is of timestamp type which has the following format: ‘YYYY-MM-DD HH:MM:SS’ or ‘2008-10-05 21:34:02.’

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$res = mysql_query("SELECT date FROM times;");
while ( $row = mysql_fetch_array($res) ) {
echo $row[’date’] . "<br />";
}

How to count values with MySQL queries

October 5th, 2008  |  by Knix  |  published in mysql

Let’s say you have the following table called votes that keeps track of how people voted and you want a query to count the number of votes for you instead of having to loop through all the rows with a counter in PHP.

person
vote

obama
yes

mccain
no

obama
yes

obama
no

mccain
yes

obama
yes

obama
yes

obama
no

mccain
no

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