How to work with data from mysql in php-multidimensional array - php

Question

I get null values when I run this code
$dataArray = mysql_query ("SELECT * from _$symbol order by date DESC limit 10;");
while ($ArrayData = mysql_fetch_assoc($dataArray)) {
$dayData [] = $ArrayData;
}
$todaysdate = $dayData[0]['date'];
$volPercentAVG = $dayData[0]['volume'] / $dayData[0]['_50dayVol'];
mysql_query ("update _$symbol set volPercentAvg=$volPercentAVG WHERE date=$todaysdate;");
It does not return anything, I am not sure I am approaching the MDarray correctly? I have triple checked the column names.
Anywhere to do with this would be helpfull
Thanks.

Answer 1

#Fred-ii- YOU DID IT! Can I or you make this an answer so I can vote for it? If I can I dont see how. – illcrx
Posting my comment as the answer in order to close the question.
If your date column contains any spaces or dots etc. then change WHERE date=$todaysdate
to/and quoting it WHERE date='$todaysdate'
For example: 2014-10-06 22:59:52
Would explain why you were not getting results.
However, I'm quite surprised/baffled that MySQL did not throw you a syntax error, bizarro.

Answer 2

Don't have time to read your entire bit right now, but I can give you my test method from our standard mysqli execution set:
print_r($Record);
This will allow you to see the structure and possibly where your error lies.
I'll also give you our framework which can be very useful (which is why we have it! LOL). Example framework (two functions) to make it easier to use mysqli in php with two lines for each query. It also allows for CLI or web output and debugging which will dump the query (so you can run it) and shows a print_r function to show results.:
This goes at the top:
define('DEBUG', false);
define('CLIDISPLAY', false);
if (CLIDISPLAY) {
define('PRE', '');
define('PRE_END', '');
} else {
define('PRE', '<pre>');
define('PRE_END', '</pre>');
}
require_once("/etc/dbconnect.php");
$DBLink = new mysqli($VARDB_server, $VARDB_user, $VARDB_pass, $VARDB_database, $VARDB_port);
if ($DBLink->connect_errno) {
printf(PRE . "Connect failed: %s\n" . PRE_END, $DBLink->connect_error);
exit();
}
Be sure you have a normal php file at /etc/dbconnect.php with your credentials in it (do not put these in a web folder in case php fails one day and exposes your passwords! LOL). Note that this file can then be shared and loaded only once. It should invoke
# Sample execution
$Query = "select * from vicidial_users where user='6666' and active='Y' limit 1";
$Records = GetData($DBLink, $Query);
print_r($Records[0]); // Single record return access via [0] to access a field named "id": $Records[0]['id']
// Multiple record return access via array walking
foreach ($Records as $Record) {
print_r($Record);
}
$Query = "update vicidial_users set active='Y' where user='6666' limit 1";
UpdateData($DBLink, $Query);
Functions (can be loaded from the credentials file or within your working file or put in a "functions.php" file and "require_once('functions.php');".
function GetData($DBLink, $Query) {
if (DEBUG) {
echo PRE . "Query: $Query\n" . PRE_END;
}
if ($Result = $DBLink->query($Query)) {
if (DEBUG) {
printf(PRE . "Affected rows (Non-Select): %d\n" . PRE_END, $DBLink->affected_rows);
}
while ($Record = $Result->fetch_assoc()) {
$ReturnData[] = $Record;
}
return $ReturnData;
} else {
if (DEBUG) {
printf(PRE . "Errormessage: %s\n", $DBLink->error);
printf("Affected rows (Non-Select): %d\n", $DBLink->affected_rows);
echo "No Records Returned\n" . PRE_END;
}
return false;
}
}
function UpdateData($DBLink, $Query) {
if (DEBUG) {
echo PRE . "Query: $Query\n" . PRE_END;
}
if ($Result = $DBLink->query($Query)) {
if (DEBUG) {
printf(PRE . "%s\n", $DBLink->info);
printf("Affected rows (Non-Select): %d\n" . PRE_END, $DBLink->affected_rows);
}
return;
} else {
if (DEBUG) {
printf(PRE . "Errormessage: %s\n", $DBLink->error);
printf("Affected rows (Non-Select): %d\n", $DBLink->affected_rows);
echo "No Records Returned\n" . PRE_END;
}
return;
}
}