Selecting data of a 'person'' using LIMIT from table - php

I was wondering how to fetch data of a person from a table. I found the query to LIMIT data fetch from table. Here is what I got so far:
$result = mysql_query("SELECT * FROM users WHERE username = '" . $username[$x] . "' LIMIT " . $last_limt . " , " . $nxt_limt . "");
It returns data when LIMIT is available but if the LIMIT exceed the entire data returns null. So how can I know if ROW is available or not in table?

use mysql Count
SELECT count(username) FROM users WHERE username ='xyz'
And your $last_limt is not grater than total count-1

You have to check number of rows of the result from that query before proceeding
$result = mysql_query("SELECT * FROM users WHERE username = '" . $username[$x] . "' LIMIT " . $last_limt . " , " . $nxt_limt . "");
$rowcount=mysql_num_rows($result);
if($rowcount > 0)
{
//next operations
}
else
{
//No more data
}

Related

Pull values from a row based on ID

Hoping someone can shed light on this. I am trying to pull the value from 2 fields from a row and based on the row being expired, exclude those 2 values from a drop down list.
I have a table (schedule)
gameID
homeID
visitorID
gameTimeEastern
weekNum
each week there are matchups where 2 teams play each other. Those 2 teams are in a row based on gameID with a specific start time (gameTimeEastern).
I have a function that determines when the matchup is locked, meaning the game has started:
function gameIsLocked($gameID) {
//find out if a game is locked
global $mysqli, $cutoffDateTime;
$sql = "select (DATE_ADD(NOW(), INTERVAL " . SERVER_TIMEZONE_OFFSET . " HOUR) > gameTimeEastern or DATE_ADD(NOW(), INTERVAL " . SERVER_TIMEZONE_OFFSET . " HOUR) > '" . $cutoffDateTime . "') as expired from " . DB_PREFIX . "schedule where gameID = " . $gameID;
$query = $mysqli->query($sql);
if ($query->num_rows > 0) {
$row = $query->fetch_assoc();
return $row['expired'];
}
$query->free;
die('Error getting game locked status: ' . $mysqli->error);
This basically determines if the row is expired (gameTimeEastern has passed). I then have a drop down on a form that has a list of all the teams from each matchup for that week.If the row is expired, then I do not want to include the homeID or visitorID from that row in the drop down.
On my page I am trying to show those teams from the expired row but it is failing as the page stops processing when it hit this:
//get expired teams
$expiredGames =gameIsLocked(gameID);
// echo 'Expired games are GAME ' . $expiredGames . '<br>';
for ($eti=1; $eti<=$gameID; $eti++)
{
if ($gameID[$eti]>''){
$sql = "select * from " . DB_PREFIX . "schedule WHERE gameID = '" . $gameID[$eti] . "';";
$query = $mysqli->query($sql);
if ($query->num_rows > 0) {
$result = $query->fetch_assoc();
$expiredHomeTeam = $result['homeID'];
$expiredVisitorTeam = $result['visitorID'];
}
}
echo 'Expired teams for GAME '.$gameID.' are '.$expiredHomeTeam.' and '.$expiredVisitorTeam.'<br>';
}
NEW CODE - Actually giving me the first result
//get expired teams
$expiredGames =gameIsLocked(gameID);
$sql = "select * from " . DB_PREFIX . "schedule WHERE weekNum = '6';";
$query = $mysqli->query($sql);
if ($query->num_rows > 0) {
$result = $query->fetch_assoc();
$expiredHomeTeam = $result['homeID'];
$expiredVisitorTeam = $result['visitorID'];
}
echo 'Expired teams for GAME ' . $expiredGames . ' are '.$expiredHomeTeam.' and '.$expiredVisitorTeam.'<br>';
Ended up using the SQL query to schedule to get results I needed. Thanks for the direction. The logic was already there, just needed to add an if statement to how I populated the array for teams in the drop down.

PHP Run query on SHOW TABLES results

How do I go about running a query on tables from a previous SHOW TABLES query? What I'm trying to do is create a PHP script that runs every 24 hours that sorts a table by "verified" descending and "votes" descending and update "nomnom" on the top result, for every table in the database.
$result = $conn->query("SHOW TABLES");
if($result->num_rows > 0) {
while($row = $result->fetch_array()) {
$sql = "SET #clan = (SELECT clan FROM " . $row[0] . " ORDER BY verified DESC, votes DESC LIMIT 1); UPDATE " . $row[0] . " SET nomnom=0 verified=0; UPDATE " . $row[0] . " SET nomnom=1 WHERE clan=#clan";
$conn->query($sql);
echo $row[0] . ' done<br>';
}
} else {
echo 'query 0';
}
This correctly echos every table name followed by done, but isn't actually updating the tables. What am I missing?
UPDATE
So I've determined that the following should work:
$sql = "SET #clan := (SELECT `clan` FROM " . $row[0] . " ORDER BY `verified` DESC, `votes` DESC LIMIT 1); UPDATE " . $row[0] . " SET `nomnom`=0, `verified`=0; UPDATE " . $row[0] . " SET `nomnom`=1 WHERE `clan`=#clan";
by echoing $sql and running the queries returned through phpmyadmin without changing anything.
Here's a line that is echoed.
SET #clan := (SELECT clan FROM aerngardh ORDER BY verified DESC, votes DESC LIMIT 1); UPDATE aerngardh SET nomnom=0, verified=0; UPDATE aerngardh SET nomnom=1 WHERE clan=#clan
It just for some reason isn't actually doing it when using
$conn->query($sql);
UPDATE 2
Figured out a way to make it work. Would mark my answer but I can't for 2 days...
Try this query
$sql = SET #clan := (SELECT clan FROM aerngardh ORDER BY verified DESC, votes DESC LIMIT 1); UPDATE aerngardh SET nomnom=0, verified=0; UPDATE aerngardh SET nomnom=1 WHERE clan=#clan
This should work
Had to split the query into 3 separate queries. Full working code:
$conn = new MySQLi($servername, $username, $password, $dbname);
$result = $conn->query("SHOW TABLES");
if($result->num_rows > 0) {
while($row = $result->fetch_array()) {
$sql = "SET #clan := (SELECT clan FROM " . $row[0] . " ORDER BY verified DESC, votes DESC LIMIT 1);";
$sql2 = "UPDATE " . $row[0] . " SET nomnom=0, verified=0;";
$sql3 = "UPDATE " . $row[0] . " SET nomnom=1 WHERE clan=#clan";
$conn->query($sql);
echo $conn->error . '<br>';
$conn->query($sql2);
echo $conn->error . '<br>';
$conn->query($sql3);
echo $conn->error . '<br>';
}
} else {
echo 'query 0';
}
If anyone would like to post how to make this a proper multi_query without getting queries out of sync errors, be my guest. I cba doing that lol.

Retrieving data belonging to a session and user id

I am trying to obtain data from the current session and the field "bidder_id" from tbl_bidder where the field "accept" has the value Accepted, but I get data of all the users in that table which is not I want. This is my code
<?php } else if (($_SESSION['Usertype']) == 'recruiter') { ?>
<table class="table table-hover">
<?php
$u_id = $_SESSION['UserID'];
$notifyR = " SELECT bidid, recbid_id, bidder_id, selected, accept FROM tbl_bides WHERE recbid_id = '" . $u_id . "'";
$ResultR = mysql_query($notifyR, $con);
while ($rowR = mysql_fetch_array($ResultR)) {
if ($rowR['accept'] == "Accepted") {
echo "<h3 style='color:#001F7A;'><b>You Have Updates </b><i class='fa fa-bell-o'></i></h3>";
echo $rowR['bidder_id'];
}
$recR = "SELECT users_id, first_name, last_name FROM tbl_users WHERE users_id = '" . $rowR['bidder_id'] . "'";
$recResultB = mysql_query($recR, $con)or die(mysql_error());
while ($rowre = mysql_fetch_array($recResultB)) {
echo " <tr><td>" . $rowre['first_name'] . " " . $rowre['last_name'] . "</td></tr>";
}
}
?>
Please help!!!
Change From
$notifyR = " SELECT bidid, recbid_id, bidder_id, selected, accept FROM tbl_bides WHERE recbid_id = '" . $u_id . "'";
To
$notifyR = " SELECT bidid, recbid_id, bidder_id, selected, accept FROM tbl_bides WHERE recbid_id = '" . $u_id . "' and accept = 'Accepted' ";
add this on your query and accept = 'Accepted' in $notifyR
I hope you might need to use the following query if you stored the user id in $_SESSION['UserID']. May be logical error: And also use mysqli_query instead of mysql_query which is deprecated in latest php versions. And instead of binding the variable directly in query, use bind param of prepared statement.
$recR = "SELECT users_id, first_name, last_name FROM tbl_users WHERE users_id = '" . $_SESSION['UserID'] . "' LIMIT 1";
If you only want to execute the second query (selecting the user associated with the given bid) when the bid has been "accepted" then you need to move that code into your conditional:
if ($rowR['accept'] == "Accepted") {
echo "<h3 style='color:#001F7A;'><b>You Have Updates </b><i class='fa fa-bell-o'></i></h3>";
echo $rowR['bidder_id'];
$recR = "SELECT users_id, first_name, last_name
FROM tbl_users
WHERE users_id = '" . $rowR['bidder_id'] . "'";
$recResultB = mysql_query($recR, $con)or die(mysql_error());
while ($rowre = mysql_fetch_array($recResultB)) {
echo " <tr><td>" . $rowre['first_name'] . " " . $rowre['last_name'] . "</td></tr>";
// echo $rowre['users_id'];
}
}
You may want to consider using a newer interface to MySQL, such as PDO, and protecting your code from SQL injection attacks by using techniques such as prepared statements or at least input cleansing.

if statement to check if mysql row exists, then selecting next query

I'm attempting to select a query to use based on the number of rows returned by a test result.
$id = mysql_real_escape_string(htmlspecialchars($_POST['id']));
$result = "SELECT FROM Notifications WHERE UserID=$id";
$r = e_mysql_query($result);
$row = mysql_fetch_array($r);
$num_results = mysql_num_rows($result);
$result = '';
if ($num_results != 0) {
$result =
"SELECT U.UserID,U.FirstName,U.LastName, " .
" DATE_FORMAT(U.BirthDate,'%m-%d-%Y') AS BirthDate, " .
" N.Email, N.Phone,N.ProviderName, N.SubNotifications " .
" FROM Users U, Notifications N " .
" WHERE U.LocationID=0 " .
" AND N.UserID='$id'";
} else {
$result =
"SELECT UserID, FirstName, LastName," .
" DATE_FORMAT(BirthDate, '%m-%d-%Y') AS BirthDate " .
" FROM Users " .
" WHERE LocationID = 0 " .
" AND UserID ='$id'";
}
echo $result;
e_mysql_result($result); //Bastardized/homegrown PDO
if ($row = mysql_fetch_assoc($result)) {
$retValue['userInfo'] = $row;
...
I'm checking the Notifications table to see if the UserID exists there, if it doesn't it loads what does exist from the Users table, if it does, then it loads everything from the Notifications table.
I'm echoing out the $result and the proper statement is loaded, but it doesn't execute. When I run the concatenated query I get from the PHP preview, it returns just fine.
Before I had to if/else this, I was running the first query, loading everything from the Notifications table, and it was loading just fine. What am I missing?
You can do the whole thing with one query with a LEFT JOIN.
$query= "SELECT U.UserID, U.FirstName,U.LastName, " .
" DATE_FORMAT(U.BirthDate,'%m-%d-%Y') AS BirthDate, " .
" N.Email, N.Phone,N.ProviderName, N.SubNotifications " .
" FROM Users U " .
" LEFT JOIN Notifications N " .
" ON U.UserID = N.UserID " .
" WHERE U.UserID = '$id'";
You are missing execute a query with mysql_query() on all $result
Also change (query variable should be quoted) so change your all variables $id quoted
$result = "SELECT FROM Notifications WHERE UserID=$id";
to
$result = "SELECT FROM Notifications WHERE UserID='$id'";
$r = mysql_query($result);
Note :- mysql_* has been deprecated use mysqli_* or PDO

Update a sql table field one time with php

Below is my small code for inserting some info into AthleteID. It doesn't actually insert the information to the table though, any help is appreciated. (sorry for asking twice, but I think my first question isn't addressing whatever issue is holding me up here!)
<?php
require_once('resources/connection.php');
echo 'hello noob' . '<br />';
$query = mysql_query('SELECT LName, MyWebSiteUserID FROM tuser WHERE MyWebSiteUserID = MyWebSiteUserID');
$athleteId = strtoupper(substr($row["LName"], 0, 2)) . $row["MyWebSiteUserID"];
$update = "UPDATE `tuser` SET `AthleteID`='$athleteId' WHERE `MyWebSiteUserID` = `MyWebSiteUserID`;";
while($row = mysql_fetch_array($query)){
mysql_query( $update);
}
Where to begin..
1) Your using mysql and not mysqli. mysql is now deprecated but you could be on a PHP 4 system so keep that in mind.
2) You are building the $athleteID before you have found out what LName and SkillshowUserID is.
3) Your using a where of 1 = 1. You dont need this as it will return true for every row.
4) So...
// Execute a query
$results = mysql_query('SELECT LName, MyWebsiteID FROM tuser WHERE SkillshowUserID = SkillshowUserID');
// Loop through the result set
while($row = mysql_fetch_array($query))
{
// Generate the athleteId
$athleteId = strtoupper(substr($row["LName"], 0, 2)) . $row["MyWebsiteID"];
// Generate an sql update statement
$update = "UPDATE `tuser` SET `AthleteID`='" . $athleteId . "' " .
" WHERE LName = '" . $row['LName'] . "' " .
" AND MyWebsiteID = '" . $row['MyWebsiteID'] . "';";
// Fire off that bad boy
mysql_query($update);
}

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