php/mysql math

[quasiman]

Hello,

I've found this script online that I'm trying to modify for my needs...still newbie at it though.
Basically it's supposed to take two values from the db table (AdmitDate and DischDate) and calculate the difference in days. If the dates are the same, make the value 1 day.

The error I'm getting is [code]Parse error: syntax error, unexpected T_ELSE in filename.php on line 13[/code]

[code]
<?php

// calculate difference and convert to days the absolute value; 1 day = 86400 s

$diff = abs($AdmitDate-$DischDate);
$diff = $diff/86400;

// remove decimals


    If ($AdmitDate == $dischDate);
        $diff = ceil($diff) + 1;
    else
       $diff = ceil($diff);

// Update records for LOS column in the database
$sql = "update PatientInfo set LOS=$diff";

// execute the select query
$open = execute_db($sql, $conn);

?>
[/code]

[redbullmarky]

might be worth checking the posting rules/etc as their is a forum for third party scripts (ie, stuff you never wrote yourself).

but hey, it's friday and i'm in a good mood so here you are:

[code]
If ($AdmitDate == $dischDate);
[/code]

the capital 'I' is not a problem, but best that it's all lower case (won't cause errors as far as i know, but i reckon it just looks rubbish). also - see the semi-colon at the end of that line? yup. you don't need it.

[code]
if ($AdmitDate == $dischDate)
[/code]

hope that helps :)

[quasiman]

AH HA!! Thank you!

Unfortunately it's not updating the days correctly, but at least I'm past the error!


Sorry it's in the wrong forum...

[AndyB]

[code]$sql = "update PatientInfo set LOS=$diff";[/code]
Assuming you only want to update one record, your query will need a WHERE clause as well ..

[code]$sql = "update PatientInfo set LOS= '$diff'  WHERE some_field = '$some_value' ";[/code]

[quasiman]

Hi AndyB,

Actually I want it to update all records. I have the script included on the index page, so on every load it updates based on the other two fields.

[Barand]

[code]mysql_query ("UPDATE mytable SET diff = (TO_DAYS(AdmitDate) - TO_DAYS(DischDate) + 1)");[/code]

[quasiman]

The Dischdate field is a date, so when I create a record and leave it blank, it has an automatic value of 0000-00-00. I want the LOS (length of stay) field to account for this and never be less than 1:

[code]if ($DischDate == 0000-00-00){
    mysql_query ("UPDATE mytable SET LOS = (TO_DAYS(AdmitDate) + 1)");
}
else {
    mysql_query ("UPDATE mytable SET LOS = (TO_DAYS(AdmitDate) - TO_DAYS(DischDate) + 1)");
}[/code]

This seems to work, but it creates records in the LOS as 732738 when there's only a 4 day difference. I'm assuming that's a date converted to a number? I have the LOS field set to VARCHAR.

[Barand]

TO_DAYS converts a DATE type field to the number of days since 1970-01-01