retrieving data from mysql DB using date comparison - php

Question

I want to send a reminder to my subscribers a month before their subscription ends, i have columns validity and reminder (type VARCHAR) in my MYSQL DB
date stored in those columns are saved using php date function
$validity = date('d/m/Y',strtotime("6 months"));
$reminder = date('d/m/Y',strtotime("5 months"));
now i want to send a mail when the current date is equals reminder date
I have a test entry with reminder value 22/06/2017 and $date variable echo the same value.
$date = date('d/m/Y');
$q = 'SELECT * FROM subscriptions WHERE reminder = "$date"';
$r = mysql_query($q);
if(!$r){
echo 'query err';
}
$a = mysql_num_rows($r);
echo 'No of rows returned '.$a;
*mailing script after this line*
this script outputs No of rows returned 0
Can someone give me some idea how i should approach this

Answer 1

First i suggest you your date format is change in database and type change datetime.
This format follow for you insert reminder date
$reminderdate = date('Y-m-d');
Then compare with currentdate when fetch data from database:
$date=date('Y-m-d');
if($r['reminder']==$date)
{
echo 'Mail sent here';
}
else
{
echo 'date not match';
}

Answer 2

Your script is at risk for SQL Injection Attacks, see this
The issue is here:
'SELECT * FROM subscriptions WHERE reminder = "$date"';
change it to:
"SELECT * FROM subscriptions WHERE reminder = '".$date."'";
to compare date, you have to wrap it into single quotes '

Answer 3

A few suggestions:
the reminder column may be redundant depending on your logic
in the future please use different approach to connect to the database, for example: http://php.net/manual/en/mysqli.quickstart.prepared-statements.php
the validity column should rather be DATETIME format
Now to your main question - it can be because of datetype mismatch so switch in database to DATETIME and in PHP use date('Y-m-d').

Answer 4

First Of all You should not store date in varachar.
Now to compare dates in varchar first you have to convert the string(varchar) into date.
for that you can use mysql's function:
str_to_date
You can get the example how to convert it and then compare it to get the result.

Answer 5

$q = "SELECT * FROM subscriptions WHERE reminder = '{$date}'";

Answer 6

I Know You have selected the answer already and ignored the comments, because you just want to get this done with and move on no matter how you did it. I will just make this answer a community WIKI.
Below are the things you need to note :
The API that you are using have depreciated for a long time ago rather use mysqli or even better PDO with prepared statements.
Also What I'm sure when the use subscrips on your website, you should have a column that stores the duration of the subscription and the actual expire date and a flag to identify expired subscriptions.
Mysql does provide its own date time functions, which you can use and use the date type on these columns.
Use API that is still active and maintained that is mysqli_* or pdo they both support prepared statements.
$host = '127.0.0.1';
$db = 'DBNAME';
$user = 'root';
$pass = '';
$charset = 'utf8';
$dsn = "mysql:host=$host;dbname=$db;charset=$charset";
$opt = array(
PDO::ATTR_ERRMODE => PDO::ERRMODE_EXCEPTION,
PDO::ATTR_DEFAULT_FETCH_MODE => PDO::FETCH_ASSOC,
PDO::ATTR_EMULATE_PREPARES => false
);
$dbh = new PDO($dsn, $user, $pass, $opt);
$stmt = $dbh->query("SELECT * FROM subscriptions WHERE subscriptionsExpireColumn = DATE_ADD(CURDATE(), INTERVAL 1 MONTH)");
if (!$stmt) {
echo "\nPDO::errorInfo():\n";
print_r($dbh->errorInfo());
} else {
$results = $stmt->fetchall();
if (count($results) > 0) {
foreach ($results as $row) {
//DO WHAT EVER YOU WANT TO DO WITH THE RESULTS
}
} else {
echo "no records found";
}
}
?>