I have a database listed as $db under mysqli. This database is contains into two tables, I listed them below as table and table2 (just for this example). Table2's rows requires an id from table. This is fine, but there might be a problem adding the columns into table2 thus requiring a rollback routine. However, it doesn't seem to be working.
I started with turning off the auto-commit. I then tried to put in the rollback command even though I am using the die command to signal a failure. As far as I am concerned the transaction could be blasted into oblivion in mid operation and the database should still be stable. So I am not sure what is going on here unless the database is completely ignoring the fact that I am trying to turn off auto-commit.
The basic structure of my code is listed below:
function problem($str)
{
global $db;
mysqli_rollback($db);
die($str);
}
mysqli_autocommit($db,false);
//Basic check if exists
$sqlstr = "SELECT * FROM table WHERE name = '$name';";
$r = mysqli_query($db,$sqlstr);
if (mysqli_num_rows($r)>0){problem("A row already exists under that id");}
//Insert the row
$sqlstr = "INSERT INTO table (name,v1,v2,v3) VALUES ('$name','$v1','$v2','$v3');";
$r = mysqli_query($db,$sqlstr);
if (!$r){problem("Could not insert into the table. $sqlstr");}
//Get the generated id part 1
$sqlstr = "SELECT id FROM table WHERE name = '$name';";
$r = mysqli_query($db,$sqlstr);
if (!$r){problem("Could not add into the table. $sqlstr");}
//Get the generated id part 2
$row = mysqli_fetch_assoc($r);
$eid = $row['id'];
//A simple loop
$count = count($questions);
for ($i=1;i<=$count;$i++)
{
//This is where it typically could die.
$r = mysqli_query($db,"INSERT INTO table2 VALUES (...);");
if (!$r){problem("Could not add to the table2. $sqlstr");}
}
mysqli_commit($db);
Is there something I am missing? I tried to follow the examples I found for the auto-commit as closely as I could.
Transactions only work if the table engine supports them, e.g. InnoDB.
Related
I need to synchronize specific information between two databases (one mysql, the other a remote hosted SQL Server database) for thousands of rows. When I execute this php file it gets stuck/timeouts after several minutes I guess, so I wonder how I can fix this issue and maybe also optimize the way of "synchronizing" it.
What the code needs to do:
Basically I want to get for every row (= one account) in my database which gets updated - two specific pieces of information (= 2 SELECT queries) from another SQL Server database. Therefore I use a foreach loop which creates 2 SQL queries for each row and afterwards I update those information into 2 columns of this row. We talk about ~10k Rows which needs to run thru this foreach loop.
My idea which may help?
I have heard about things like PDO Transactions which should collect all those queries and sending them afterwards in a package of all SELECT queries, but I have no idea whether I use them correctly or whether they even help in such cases.
This is my current code, which is timing out after few minutes:
// DBH => MSSQL DB | DB => MySQL DB
$dbh->beginTransaction();
// Get all referral IDs which needs to be updated:
$listAccounts = "SELECT * FROM Gifting WHERE refsCompleted <= 100 ORDER BY idGifting ASC";
$ps_listAccounts = $db->prepare($listAccounts);
$ps_listAccounts->execute();
foreach($ps_listAccounts as $row) {
$refid=$row['refId'];
// Refsinserted
$refsInserted = "SELECT count(username) as done FROM accounts WHERE referral='$refid'";
$ps_refsInserted = $dbh->prepare($refsInserted);
$ps_refsInserted->execute();
$row = $ps_refsInserted->fetch();
$refsInserted = $row['done'];
// Refscompleted
$refsCompleted = "SELECT count(username) as done FROM accounts WHERE referral='$refid' AND finished=1";
$ps_refsCompleted = $dbh->prepare($refsCompleted);
$ps_refsCompleted->execute();
$row2 = $ps_refsCompleted->fetch();
$refsCompleted = $row2['done'];
// Update fields for local order db
$updateGifting = "UPDATE Gifting SET refsInserted = :refsInserted, refsCompleted = :refsCompleted WHERE refId = :refId";
$ps_updateGifting = $db->prepare($updateGifting);
$ps_updateGifting->bindParam(':refsInserted', $refsInserted);
$ps_updateGifting->bindParam(':refsCompleted', $refsCompleted);
$ps_updateGifting->bindParam(':refId', $refid);
$ps_updateGifting->execute();
echo "$refid: $refsInserted Refs inserted / $refsCompleted Refs completed<br>";
}
$dbh->commit();
You can do all of that in one query with a correlated sub-query:
UPDATE Gifting
SET
refsInserted=(SELECT COUNT(USERNAME)
FROM accounts
WHERE referral=Gifting.refId),
refsCompleted=(SELECT COUNT(USERNAME)
FROM accounts
WHERE referral=Gifting.refId
AND finished=1)
A correlated sub-query is essentially using a sub-query (query within a query) that references the parent query. So notice that in each of the sub-queries I am referencing the Gifting.refId column in the where clause of each sub-query. While this isn't the best for performance because each of those sub-queries still has to run independent of the other queries, it would perform much better (and likely as good as you are going to get) than what you have there.
Edit:
And just for reference. I don't know if a transaction will help here at all. Typically they are used when you have several queries that depend on each other and to give you a way to rollback if one fails. For example, banking transactions. You don't want the balance to deduct some amount until a purchase has been inserted. And if the purchase fails inserting for some reason, you want to rollback the change to the balance. So when inserting a purchase, you start a transaction, run the update balance query and the insert purchase query and only if both go in correctly and have been validated do you commit to save.
Edit2:
If I were doing this, without doing an export/import this is what I would do. This makes a few assumptions though. First is that you are using a mssql 2008 or newer and second is that the referral id is always a number. I'm also using a temp table that I insert numbers into because you can insert multiple rows easily with a single query and then run a single update query to update the gifting table. This temp table follows the structure CREATE TABLE tempTable (refId int, done int, total int).
//get list of referral accounts
//if you are using one column, only query for one column
$listAccounts = "SELECT DISTINCT refId FROM Gifting WHERE refsCompleted <= 100 ORDER BY idGifting ASC";
$ps_listAccounts = $db->prepare($listAccounts);
$ps_listAccounts->execute();
//loop over and get list of refIds from above.
$refIds = array();
foreach($ps_listAccounts as $row){
$refIds[] = $row['refId'];
}
if(count($refIds) > 0){
//implode into string for use in query below
$refIds = implode(',',$refIds);
//select out total count
$totalCount = "SELECT referral, COUNT(username) AS cnt FROM accounts WHERE referral IN ($refIds) GROUP BY referral";
$ps_totalCounts = $dbh->prepare($totalCount);
$ps_totalCounts->execute();
//add to array of counts
$counts = array();
//loop over total counts
foreach($ps_totalCounts as $row){
//if referral id not found, add it
if(!isset($counts[$row['referral']])){
$counts[$row['referral']] = array('total'=>0,'done'=>0);
}
//add to count
$counts[$row['referral']]['total'] += $row['cnt'];
}
$doneCount = "SELECT referral, COUNT(username) AS cnt FROM accounts WHERE finished=1 AND referral IN ($refIds) GROUP BY referral";
$ps_doneCounts = $dbh->prepare($doneCount);
$ps_doneCounts->execute();
//loop over total counts
foreach($ps_totalCounts as $row){
//if referral id not found, add it
if(!isset($counts[$row['referral']])){
$counts[$row['referral']] = array('total'=>0,'done'=>0);
}
//add to count
$counts[$row['referral']]['done'] += $row['cnt'];
}
//now loop over counts and generate insert queries to a temp table.
//I suggest using a temp table because you can insert multiple rows
//in one query and then the update is one query.
$sqlInsertList = array();
foreach($count as $refId=>$count){
$sqlInsertList[] = "({$refId}, {$count['done']}, {$count['total']})";
}
//clear out the temp table first so we are only inserting new rows
$truncSql = "TRUNCATE TABLE tempTable";
$ps_trunc = $db->prepare($truncSql);
$ps_trunc->execute();
//make insert sql with multiple insert rows
$insertSql = "INSERT INTO tempTable (refId, done, total) VALUES ".implode(',',$sqlInsertList);
//prepare sql for insert into mssql
$ps_insert = $db->prepare($insertSql);
$ps_insert->execute();
//sql to update existing rows
$updateSql = "UPDATE Gifting
SET refsInserted=(SELECT total FROM tempTable WHERE refId=Gifting.refId),
refsCompleted=(SELECT done FROM tempTable WHERE refId=Gifting.refId)
WHERE refId IN (SELECT refId FROM tempTable)
AND refsCompleted <= 100";
$ps_update = $db->prepare($updateSql);
$ps_update->execute();
} else {
echo "There were no reference ids found from \$dbh";
}
I have two tables. One table is the matches table (e2wedstrijden) and another table is my scoring table with the points earned etc. (e2teams).
Now I have that I can delete a match from the e2wedstrijden table. And this is working fine.
But I want that if I delete a match from that table. It also add or decrease points to the table ("e2teams"). I tried to compare the tables but this is not working.
So I want for example:
If($row['thuisscore'] == $row['uitscore']) what are to row names in my e2wedstrijden table. So if these two are the same (like 0-0 or 1-1 or something) Than it needs to decrease 1 point from the table e2teams. But only by the teams that are the same as the rows "Thuisteam" and "Uitteam" in my e2wedstrijden table. So the Row Thuisteam (in "e2wedstrijden") Needs to find the same result in ("e2teams") row Team. And this needs to be done the same with the Row Uitteam (in "e2wedstrijden") Needs to find the same result in ("e2teams")
Thuisteam and Uitteam = Dutch for hometeam and awayteam. I think my fault is that the system can't link the 'Thuisteam' from e2wedstrijden to the Team in e2teams but don't know how to solve it
This is my deletematches.php, It deletes the match but doesn't decrease or adds points:
<?php
if(!isset($_COOKIE['E2ingelogd'])) {
header("location:../../index.php");
}
include "../../connect.php";
$dbhandle = mysql_connect($hostname, $username, $password) or die("Could not connect to database");
$selected = mysql_select_db("login", $dbhandle);
$result = mysql_query("SELECT * FROM e2wedstrijden WHERE ID = ".$_GET['del']."");
while($row = mysql_fetch_assoc($result)){
if( $row['thuisscore'] == $row['uitscore']){
echo $row['thuisscore'];
mysql_query("UPDATE e2teams SET Punten = Punten-1 WHERE Team ='".$row['Thuisteam']."'");
mysql_query("UPDATE e2teams SET Gespeeld = Gespeeld-1 WHERE Team = ('".$row['Thuisteam']."'");
mysql_query("UPDATE e2teams SET Verloren = Gelijk-1 WHERE Team ='".$row['Uitteam']."'");
echo "Team is deleted";
}else{
echo 'Update Error!';
}
}
$table_1_delete = mysql_query("DELETE FROM e2wedstrijden WHERE ID = ".$_GET['del']."");
?>
This is my e2teams table:
And this is my E2wedstrijden table:
So i need something like:
UPDATE e2teams SET Punten = Punten-1 WHERE Team = Look in table ("e2wedstrijden) deleted Thuisteam and deleted Uitteam
Hope you can help
You've placed an extra parentheses in the 2nd query for "gespeeld" right after the equal sign:
mysql_query("UPDATE e2teams SET Gespeeld = Gespeeld-1
WHERE Team = ('".$row['Thuisteam']."'");
Is this what isn't updating?
Without being 100% sure on how your data model works, it might make sense at refactoring what you have. Something that might be useful would be to create a view of the summary table and just update the data from the child/master table.... aggregating in the view layer. Views in mysql can be seen here.
If you are stuck with the data model you have (legacy application, etc.) you can possibly look at triggers if you have to modify data in two tables you might want to consider stored procedures or triggers, discussed here and here.
The third thing that comes to mind, is around correlated sub-queries and how you could reference the another table in a sort of update-from. However, you're ID's aren't surrogate keys in this situation.
Also, have a look at sql injection; I haven't looked at PHP in a while but those sql statements kind of look like they are created with sting composition
Good luck,
I'm building a simple bug tracking tool.
When you create a new project, all the info you fill in in the form, gets stored in the database.
When you create the new project you get redirected to a unique project page.
On top of the page it shows the name of the project, but it's not the name of the project I just created, it always shows the name of the first project in the MySQL table.
How can I show the name of the project I just created?
With this query I retrieve the data from the database.
$query = "SELECT CONCAT(name)
AS name FROM projects";
$result = #mysql_query ($query)
With this I show the project name, but it always shows the name of the first record in the table.
<?php
if ($row = mysql_fetch_array ($result))
echo '<h5>' . $row['name'] . '</h5>';
?>
It isn't yet SQL Injection prove and is far from complete... But I'm really struggling with this problem.
You need an AUTO_INCREMENT field on your table for a unique identifier (at least, you really should). Then you can do something like this:
<?php
$sql = new MySQLi('localhost', 'root', '', 'database');
$sql->query('INSERT INTO `projects` (`name`) VALUES ("Test Project");');
$projectID = $sql->insert_id; // Returns the auto_increment field value of the last insert query performed
// So this assumes you have a field in your table called "id" in this example
$res = $sql->query('SELECT CONCAT(`name`) AS `name` FROM `projects` WHERE `id` = '.$projectID.';');
if ($row = $res->fetch_assoc()) {
echo '<h5>'.$row['name'].'</h5>';
}
?>
Since you were calling for a redirect to the unique project page, you should have something like this: header("Location: project.php?id=$projectID");
Then, on project.php, you can attempt to fetch the project with the query above, only your query's WHERE clause should be something like:
'`id` = '.intval($_GET['id']).';'
Technically, you could pass all the project info along to the next page as a request or a session cookie and save yourself a query altogether. Just make sure you keep the id handy so it's easy to update the record.
Try using ORDER BY.
$query = "SELECT CONCAT(name)
AS name FROM projects ORDER BY id DESC";
This would show the most recent project (assuming you have an ID column).
However, a much better way is to have an ID variable on the page.
$query = "SELECT CONCAT(name)
AS name FROM projects WHERE id=?";
I'm not sure how to accomplish this issue which has been confusing me for a few days. I have a form that updates a user record in MySQL when a checkbox is checked. Now, this is how my form does this:
if (isset($_POST['Update'])) {
$paymentr = $_POST['paymentr']; //put checkboxes array into variable
$paymentr2 = implode(', ', $paymentr); //implode array for mysql
$query = "UPDATE transactions SET paymentreceived=NULL";
$result = mysql_query($query);
$query = "UPDATE transactions SET paymentdate='0000-00-00'";
$result = mysql_query($query);
$query = "UPDATE transactions SET paymentreceived='Yes' WHERE id IN ($paymentr2)";
$result = mysql_query($query);
$query = "UPDATE transactions SET paymentdate=NOW() WHERE id IN ($paymentr2)";
$result = mysql_query($query);
foreach ($paymentr as $v) { //should collect last updated records and put them into variable for emailing.
$query = "SELECT id, refid, affid FROM transactions WHERE id = '$v'";
$result = mysql_query($query) or die("Query Failed: ".mysql_errno()." - ".mysql_error()."<BR>\n$query<BR>\n");
$trans = mysql_fetch_array($result, MYSQL_ASSOC);
$transactions .= '<br>User ID:'.$trans['id'].' -- '.$trans['refid'].' -- '.$trans['affid'].'<br>';
}
}
Unfortunately, it then updates ALL the user records with the latest date which is not what I want it to do. The alternative I thought of was, via Javascript, giving the checkbox a value that would be dynamically updated when the user selected it. Then, only THOSE checkboxes would be put into the array. Is this possible? Is there a better solution? I'm not even sure I could wrap my brain around how to do that WITH Javascript. Does the answer perhaps lie in how my mysql code is written?
--
Edit: Ok, just more information. The SQL Queries I have going on - the first two are to wipe everything clean (in case a checkbox is UNCHECKED) and then next they are updating the SQL queries based on which checkboxes are checked upon post.
However, I'm thinking this is a bad way to do it. Why force the database to first wipe out ALL data for paymetreceived, paymetdate? The problem with this, also, is that *all the subsequent checkboxes, regardless of how long ago they were checked, get updated in the SQL query as it is now.*There's got to be a way to update it better. I'm just not sure HOW to do it. any ideas?
You are not filtering by id in this queries:
$query = "UPDATE transactions SET paymentreceived=NULL";
$query = "UPDATE transactions SET paymentdate='0000-00-00'";
Try adding: WHERE id IN ($paymentr2)";
The problem is in your first 2 sql UPDATE statements. You don't provide a WHERE clause, so that's going to update all your records. You could add:
WHERE id IN ($paymentr2)
to your first two UPDATE statements
Hey, I have a field called STATUS and it is either 1 to show or 0 to hide. My code is below. I am using an edit in place editor with jQuery. Everytime you update it creates a new ROW which I want, but I want only the new one to have STATUS = 1 and the others to 0. Any ideas on how I would do that?
<?php
include "../../inc/config.inc.php";
$temp = explode("_", $_REQUEST['element_id'] );
$field = $temp[0];
$id = $temp[1];
$textboxval = stripslashes(mysql_real_escape_string(preg_replace('/[\$]/',"",$_REQUEST["update_value"])));
$query = "INSERT INTO notes ($field,status,date,c_id) VALUES ('$textboxval','1',NOW(),'$id')";
mysql_query($query);
echo($_REQUEST['update_value']);
?>
I am not sure exactly what you mean - do you want to make all the entries except the new one have status = 0? If so, just issue an update before the insert:
UPDATE notes SET status = 0
However, I should also note that you have a potential SQL injection to worry about. By stripping slashes after applying "mysql real escape string", you are potentially allowing someone to put text in your SQL statement that will execute an arbitrary SQL statement.
Something like this, sorry for the post before, I mis read it the first time then went back:
<?php
include "../../inc/config.inc.php";
$temp = explode("_", $_REQUEST['element_id'] );
$field = $temp[0];
$id = $temp[1];
$textboxval = mysql_real_escape_stringstripslashes((preg_replace('/[\$]/',"",$_REQUEST["update_value"])));
// set older entries to 0 - to not show but show in history
$hide_notes = "UPDATE notes SET status = 0";
mysql_query($hide_notes);
// add new entry with status of 1 to show only latest note
$query = "INSERT INTO notes ($field,status,date,c_id) VALUES ('$textboxval','1',NOW(),'$id')";
mysql_query($query);
echo($_REQUEST['update_value']);
?>
i just ran in to a problem I didn't of the set up of my table doesn't allow me to show more than one client a time and i will be having numerous clients, my bad on planning ha
You really want to get the ID of the newly generated row and then trigger an UPDATE where you all rows where the ID is not the new row, e.g.
UPDATE notes SET status = 0 WHERE id != $newly_generated_id
If the ID column in your table is using AUTO_INCREMENT you can get its ID via "SELECT LAST_INSERT_ID()" and then use the return value in that statement in your UPDATE statement.
Pseudo code:
$insert = mysql_query("INSERT INTO ...");
$last_id = mysql_query("SELECT LAST_INSERT_ID()");
$update = mysql_quqery("UPDATE notes SET status = 0 WHERE id != $last_id");
The only caveat to this approach is where you might have a brief moment in time where 2 rows have status=1 (the time between your INSERT and the UPDATE). I would wrap all of this in a transaction to make the whole unit more atomic.