PHP Comparing date in table with current date - php

I am trying to compare a stored date to the current date, and send back data accordingly. I'm not fluent in PHP so this is what I have so far
while ($row = mysql_fetch_array($result)) {
// temp user array
$event_date_str = $row["date"];
$todays_date_str = date("m-j-Y");
$today = strtotime($todays_date_str);
$event_date = strtotime($event_date_str);
if($event_date > $today){
$event = array();
$event["pid"] = $row["pid"];
$event["name"] = $row["name"];
$event["longitude"] = $row["longitude"];
$event["latitude"] = $row["latitude"];
$event["pavement"] = $row["pavement"];
$event["traffic"] = $row["traffic"];
$event["environment"] = $row["environment"];
$event["image_b64"] = $row["image_b64"];
$event["created_at"] = $row["created_at"];
$event["date"] = $row["date"];
$event["time"] = $row["time"];
$event["type"] = $row["type"];
// push single product into final response array
array_push($response["events"], $event);
}else{
//delete it here
}
With that code right there I am getting nothing back. I have 2 items stored in the database, One with the date "2-28-2014" and another with "2-14-2014", so I should be getting one back and not the other but I am getting neither back. I know that there are no leading zeros with the dates saved so I should use j right? Could someone help me figure out why this is not working, sorry if it seems like a simple question.
Thank you in advance,
Tyler

This is not an efficient way to do things. If you need to pick items based on date, do it in the MySQL query directly. PHP filtering will always be slower than MySQL. Especially since you have to deliver extra data over network when filtering at PHP level.
So do it like this:
SELECT * FROM `table` WHERE `record_expires_datetime_gmt` > UTC_TIMESTAMP();
SELECT * FROM `table` WHERE `record_expires_date_gmt` > DATE(UTC_TIMESTAMP());
// use NOW() for local time, UTC_TIMESTAMP() is GMT/UTC
Then do what you need to do with the records. Never SELECT * and then filter records in PHP.
There's a whole set of DATETIME functions in MySQL to allow you MySQL server side filtering of data.
PS: Obviously, for this method to work, your MySQL table has to be properly designed. Date (date and time) fields need to be of type DATE or DATETIME not surrogate strings that are meaningful only within your project.

Related

Time Calculations with MySQL

I'm writing a time logging programme for a client who is a piano tuner, and I've written the following PHP code to give a record a status of 'to do':
$last_tuned = '2017-01-05';
$tuning_period = 3;
$month_last_tuned = date('Y-m', strtotime(date('Y-m-d', strtotime($last_tuned))));
$next_tuning = date('Y-m', strtotime($month_last_tuned.(' +'.$tuning_period.' months')));
if (time() > strtotime($next_tuning.' -1 months')) {
if (time() > strtotime($next_tuning)) {
return 'late';
} else {
return 'upcoming';
}
}
As you can see, the $last_tuned variable is of the date(YYYY-MM-DD) format. This is then converted to a (YYYY-MM) format.
Once convered, an additional number of months, identical to $tuning_period is then added to the $month_last_tuned variable giving us a month and year value for when we need to add a new record.
If the current time (found with time()) is greater than the $next_tuning variable - 1 month, it returns that the task is upcoming. If it's after the $next_tuning variable, it returns that the task is late.
I now have to write a MySQL query to list the items that would return as upcoming or late.
How would I write this in MySQL? I'm not very good with MySQL functions, and some help would be much appreciated.
My attempt at the logic is:
SELECT * FROM records
// The next lines are to get the most recent month_last_tuned value and add the tuning_period variable
WHERE
NOW() > (SELECT tuning_date FROM tunings ORDER BY tuning_date ASC LIMIT 1)
+
(SELECT tuning_period FROM records WHERE records.id = INITIAL CUSTOMER ID)
I know that that is completely wrong. The logic is pretty much there though.
My database schema is as follows:
I expect the rows returned from the query to be on-par with the 'late' or 'upcoming' values in the PHP Code above. This means that the rows returned will be within 1 months of their next tuning date (calculated from last tuning plus tuning period).
Thanks!
You'd probably be better off with using the DateTime object instead of manipulating date strings.
$last_tuned = '2017-01-05';
$tuning_period = 3; // months
$dt_last_tuned = DateTimeImmutable::createFromFormat('Y-m-d',$last_tuned);
$dt_next_tuning = $dt_last_tuned->add(new DateInterval('P3M'));
$dt_now = new DateTimeImmutable();
$dt_tuning_upcoming = $dt_next_tuning->sub(new DateInterval('P1M'));
if( $dt_now > $dt_next_tuning) {
return 'late';
}
if( $dt_now > $dt_tuning_upcoming) {
return 'upcoming';
}
You can also use these DateTime objects in your MySQL queries, by building the query and passing through something like $dt_next_tuning->format('Y-m-d H:i:s'); as needed.
Given your table structure, however, it may be easier to just get all the relevant records and process them. It's a little difficult to tell exactly how the pieces fit together, but generally speaking MySQL shouldn't be used for "processing" stuff.

How to transform a PHP loop to a MySQL query?

I am trying to make a PHP loop work for me in MySQL. Currently all visits to a website via a specific URL parameterare logged into a table along with the date and time of the visit. I am rebuilding the logging procedure to only count the visits via one specific parameter on one day, but I'll have to convert the old data first.
So here's what I'm trying to do: The MySQL table (let's call it my_visits) has 3 columns: parameter, visit_id and time.
In my PHP code, I've created the following loop to gather the data I need (all visits made via one paramter on one day, for all parameters):
foreach (range(2008, 2014) as $year) {
$visit_data = array();
$date_ts = strtotime($year . '-01-01');
while ($date_ts <= strtotime($year . '-12-31')) {
$date = date('Y-m-d', $date_ts);
$date_ts += 86400;
// count visit data
$sql = 'SELECT parameter, COUNT(parameter) AS total ' .
'FROM my_visits ' .
'WHERE time BETWEEN \''.$date.' 00:00\' AND \''.$date.' 23:59\' '.
'GROUP BY parameter ORDER BY total DESC';
$stmt = $db->prepare($sql);
$stmt->execute(array($date));
while ($row = $stmt->fetch()) {
$visit_data[] = array(
'param' => $row['parameter'],
'visit_count' => $row['total'],
'date' => $date);
}
$stmt->closeCursor();
}
}
Later on, the gathered data is inserted into a new table (basically eliminating visit_id) using a multiple INSERT (thanks to SO! :)).
The above code works, but due to the size of the table (roughly 3.4 million rows) it is very slow. Using 7 * 365 SQL queries just to gather the data seems just wrong to me and I fear the impact of just running the script will slow everything down substantially.
Is there a way to make this loop work in MySQL, like an equivalent query or something (on a yearly basis perhaps)? I've already tried a solution using GROUP BY, but since this eliminates either the specific dates or the parameters, I can't get it to work.
You can GROUP further.
SELECT `parameter`, COUNT(`parameter`) AS `total`, DATE(`time`) AS `date`
FROM `my_visits`
GROUP BY `parameter`, DATE(`time`)
You can then execute it once (instead of in a loop) and use $row['date'] instead of $date.
This also means you don't have to update your code when we reach 2015 ;)

Comparison between a timestamp in MYSQL table with a PHP variable NOT Working - PHP MYSQL

I'm trying to filter out repeated values entering into a MySQL table, by comparing the input PHP variable with the timestamp of an entry already present in the table and only if they don't match, the input PHP variable is entered into the table.
$user1_date = mysql_real_escape_string($user1_date); // the date variable
$user1_temp1 = mysql_real_escape_string($user1_temp1);
$user1_temp2 = mysql_real_escape_string($user1_temp2);
$user1_temp3 = mysql_real_escape_string($user1_temp3);
$user1_date = date("Y-m-d H:i:s", strtotime($user1_date)); //Typecasting PHP variable into timestamp
$sql_check = "SELECT * FROM user_details WHERE temp_date ='$user1_date'";
$result_check = mysql_query($sql_check);
$num_rows_check = mysql_num_rows($result_check);
if ($num_rows_check == 0) // To check if there is no entry in the table with the same date and time as input PHP variable
{
$sql_insert = "INSERT INTO data_hour (user_id, temp1, temp_date, temp2, temp3)
VALUES (1,'$user1_temp1', '$user1_date', '$user1_temp2', '$user1_temp3')";
$result_insert = mysql_query($sql_insert);
}
temp_date is a column in the table of type timestamp. Even when the $user1_date is the same as the temp_date(timestamp) column for one of the entries in the table, it considers it as not equal and is inserting it into the table and hence I'm getting repeated values. I'm guessing the WHERE temp_date = '$user1_date'is not working properly. Some troubleshooting that I have done included
Changing '$user1_date' to just $user1_date in the WHERE
statement
Changing the WHERE clause as follows WHERE temp_date = (date)'$user1_date'
It will be great if somebody can help me out with this!
A nice easy solution would be giving temp_date a UNIQUE INDEX in your Mysql Table, as that would not allow the same value to be inserted twice. This would also make your operations more efficient, as you wouldn't have to do SELECT * every time you want to insert something.
However, for what you're doing, I think I see your problem; there are some quirks in your logic so I'll try to dispel them here. (Hopefully?) this will make your program cleaner and you'll be able to pinpoint the error, if not eliminate it altogether.
Examining this piece of code:
// $user1_date doesn't have a value here! //
$user1_date = mysql_real_escape_string($user1_date);
...
$user1_date = date("Y-m-d H:i:s", strtotime($user1_date));
Error 1 - You escape the string before ever setting a value.
What you are doing is that you are using mysql_real_escape_string() before $user1_date is ever defined.
Correction:
// Getting better, but not done. //
$user1_date = date("Y-m-d H:i:s", strtotime($user1_date));
...
$user1_date = mysql_real_escape_string($user1_date);
Error 2 - You do not give the date() function appropriate parameters
The date() function in PHP expects a timestamp, which is just an int. You can easily get the time with time(), so that should rectify your problem
Correction:
// You use strtotime($user1_date), but you should use time() //
$user1_date = date("Y-m-d H:i:s", time());
...
$user1_date = mysql_real_escape_string($user1_date);
These are small mistakes, but they can be deadly. Like I said, you should assign temp_date to a UNIQUE INDEX in your MySQL table, but make sure to correct these errors listed as well.
Let me know how it goes!

MySQL - Compare all values in a column and write in another column

I need to create a script that compares one field in the database (has a date stored, it's type is "TEXT" and cannot be changed DATE) to the current server date.
The dates are encoded like this "1380571547", so i need to use strftime() to decode them. This field for example, decoded with strftime corresponds to this "Sep-30-2013, 22:05"
What I need is to compare those fields with the current date, and according to that condition, write something like "Expired" in another field.
To achieve this, I made this block of code:
<?php
require("connection.php");
$today = strftime('%b-%d-%Y, %H:%M');
$exp_date = mysql_query("SELECT numbers FROM date");
while($row = mysql_fetch_array($exp_date))
{
echo (strftime ( '%b-%d-%Y, %H:%M', $row ['numbers'])). "<br />";
}
if ($exp_date < $today) {
$sql = "INSERT INTO date (changed) VALUES ('EXPIRED')";
$result = mysql_query($sql);
echo "ADDED!";
}
?>
However, this code is not working, can someone help me ?
PHP is not my strong point but it looks to me like you condition is doing a comparison on an array,
IE:
if ($exp_date < $today) // will always be false.
Your code would probably have to look something more like this.
while($row = mysql_fetch_array($exp_date))
{
if ($row[0] < $today)
{
$sql = "Update date set changed = VALUE where rowid = rowid";
$result = mysql_query($sql);
echo "ADDED!";
}
}
having said that i would probably do the comparison and update in SQL using a case statement,
Update Date
set changed = case when number > ExpiryDate
then "Expired"
else "Current"
end
You can do all this in a single query:
UPDATE `date` set `changed`='Expired' where date(now()) > date(from_unixtime(`numbers`))
But this is not what your code is attempting to do. Your second block seems to be inserting the word Expired in new rows, rather than updating anything.
Note that the table name date should be wrapped in backticks to avoid any possible clash with MySQL keywords
I don't understand the second block of code with the insert. I would do an update inside the loop. but if your going to do that, it could probably be done in one combined update statement.

PHP: mysql_fetch_array() in a while-loop takes too long

I am creating an online calendar for a client using PHP/MySQL.
I initiated a <table> and <tr>, and after that have a while loop that creates a new <td> for each day, up to the max number of days in the month.
The line after the <td>, PHP searches a MySQL database for any events that occur on that day by comparing the value of $i (the counter) to the value of the formatted Unix timestamp within that row of the database. In order to increment the internal row counter ONLY when a match is made, I have made another while loop that fetches a new array for the result. It is significantly slowing down loading time.
Here's the code, shortened so you don't have to read the unnecessary stuff:
$qry = "SELECT * FROM events WHERE author=\"$author\"";
$result = mysql_query($qry) or die(mysql_error());
$row = mysql_fetch_array($result);
for ($i = 1; $i <= $max_days; $i++) {
echo "<td class=\"day\">";
$rowunixdate_number = date("j", $row['unixdate']);
if ($rowunixdate_number == $i) {
while ($rowunixdate_number == $i) {
$rowtitle = $row['title'];
echo $rowtitle;
$row = mysql_fetch_array($result);
$rowunixdate_number = date("j", $row['unixdate']);
}
}
echo "</td>";
if (newWeek($day_count)) {
echo "</tr><tr>";
}
$day_count++;
}
The slowness is most likely because you're doing 31 queries, instead of 1 query before you build the HTML table, as Nael El Shawwa pointed out -- if you're trying to get all the upcoming events for a given author for the month, you should select that in a single SQL query, and then iterate over the result set to actually generate the table. E.g.
$sql = "SELECT * FROM events WHERE author = '$author' ORDER BY xdate ASC";
$rsEvents = mysql_query($sql);
echo("<table><tr>");
while ($Event = mysql_fetch_array($rsEvents)) {
echo("<td>[event info in $Event goes here]</td>");
}
echo("</tr></table>");
Furthermore, it's usually a bad idea to intermix SQL queries and HTML generation. Your external data should be gathered in one place, the output data generated in another. My example cuts it close, by having the SQL immediately before the HTML generation, but that's still better than having an HTML block contain SQL queries right in the middle of it.
Have you run that query in a MySQL tool to see how long it takes?
Do you have an index on the author column?
There's nothing wrong with your PHP. I suspect the query is the problem and no index is the cause.
aside from their comments above, also try to optimize your sql query since this is one of the most common source of performance issues.
let say you have a news article table with Title, Date, Blurb, Content fields and you only need to fetch the title and display them as a list on the html page,
to do a "SELECT * FROM TABLE"
means that you are requiring the db server to fetch all the field data when doing the loop (including the Blurb and Content which you are not going to use).
if you optimize that to something like:
"SELECT Title, Date FROM TABLE" would fetch only the necessary data and would be more efficient in terms of server utilization.
i hope this helps you.
Is 'author' an id? or a string? Either way an index would help you.
The query is not slow, its the for loop thats causing the problem. Its not complete; missing the $i loop condition and increment. Or is this a typo?
Why don't you just order the query by the date?
SELECT * FROM events WHERE author=? ORDER BY unixdate ASC
and have a variable to store the current date you are on to have any logic required to group events by date in your table ex. giving all event rows with the same date the same color.
Assuming the date is a unix timestamp that does not account for the event's time then you can do this:
$currentDate = 0;
while(mysql_fetch_array($result)){
if($currentDate == $row['unixdate']){
//code to present an event that is on the same day as the previous event
}else{
//code to present an even on a date that is past the previous event
//you are sorting events by date in the query
}
//update currentDate for next iteration
$currentDate = $row['unixdate'];
}
if unixdate includes the event time, then you need to add some logic to just extract the unix date timestmap excluding the hours and minutes.
Hope that helps

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