I have 2 queries that I want to compare and display
Compare the 2 queries for matching
if match show image, if not show placeholder image
$variable1 = " SELECT * FROM
(
SELECT img, ID from tbl1
UNION DISTINCT
SELECT img, ID from tbl2
) as everything";
while($a = mysqli_fetch_array...){
$row1 = $a['img'];
$rowA = $a['ID'];
}
Compare with
$variable2 = "SELECT img, ID FROM tbl3";
while($b = mysqli_fetch_array...){
$row2 = $b['img'];
$rowB = $b['ID'];
}
I tried the foreach looping through each row to compare
foreach($rowB as $rowC){
if($rowC == $rowA)...
echo'<table>'.$row1.'</table>';
}else{
echo'<table>'.$row2.'</table>';
}
Seems like the entire result is repeated by the number of matches. I tried nesting one query into the other along with a host of other trials. Could use some guidance.
Related
I have a code in PHP where I want to display multiple times values, and so, even if these values are the same between them. My code is simple :
$sql = "SELECT photo from table WHERE username IN ('1','2','2') ORDER BY id DESC ";
$res = array();
$result = mysqli_query($con,$sql);
while($row = mysqli_fetch_array($result)){
array_push($res, $row['photo']);
}
echo json_encode($res);
But this code only display (in json) an array of two values (because the values of photo of the username 2 are the same).
What I want to achieve is to make an array with the exact same number of values of the number of username I defined WHERE username IN ('1','2','2') (so here, 3 values).
I hope you understood me, thanks for helping me !
I think what you're after is to list even the duplicates in the end result. As your SQL will only retrieve the unique items, the idea would be to include the username in the SQL result set. Then use the original list of user names ($userNames) and add in the photo for each of them.
I've used mysqli_fetch_all() to simplify the process of fetching all of the data, then used array_column() to make the username the key for the photos.
$userNames = array(1,2,2);
$sql = "SELECT username, photo
from table
WHERE username IN ('".implode("','", $userNames)."')
ORDER BY id DESC ";
$res = array();
$result = mysqli_query($con,$sql);
$photos = mysqli_fetch_all($result, MYSQLI_ASSOC);
$photos = array_column($photos, "photo", "username");
foreach ( $userNames as $user ) {
if ( isset($photos[$user])) {
$res[] = $photos[$user];
}
else {
$res[] = '';
}
}
echo json_encode($res);
You would use left join:
select t.photo
from (select '1' as username union all select '2' union all select '3'
) u left join
table t
on t.username = u.username
order by t.id desc;
Note this will return rows, even when the user name does not exist. If you want to filter those rows, remove the left so you are doing an inner join.
I'm trying to show stuff queried from two tables, but on one html table. Data is shown for the last 30 days, based on which, an html table is being generated.
Currently I'm stuck using two queries and generating two html tables:
$query1 = mysqli_query( $con, "SELECT date, stuff* " );
while( $record = mysqli_fetch_array( $query1 ) ){
echo '<html table generated based on query>';
}
$query2 = mysqli_query( $con, "SELECT date, other stuff*" );
while( $record = mysqli_fetch_array( $query2 ) ){
echo '<another html table generated based on query2>';
}
Is there a possibility to show both queries on one html table instead?
Note that it gets tricky since we have dates on one table which are not necessarily found in the second table or vice-versa.
Thanks for the support guys. So far I'm stuck at this:
SELECT * FROM user_visit_logs
LEFT JOIN surfer_stats ON user_visit_logs.date = surfer_stats.date
UNION
SELECT * FROM user_visit_logs
RIGHT JOIN surfer_stats ON user_visit_logs.date = surfer_stats.date
The query completes, but the 2nd table fields are all null:
Furthermore, it breaks when I add additional clause like:
WHERE user_id = '{$_SESSION['user_id']}' ORDER BY date DESC LIMIT 30
I think you are after FULL OUTER JOIN concept:
The FULL OUTER JOIN keyword returns all rows from the left table (table1) and from the right table (table2)
In which you may use common dates as a shared row.
So the query will get to simple one:
$query = "
SELECT table1.date, stuff
FROM table1
LEFT OUTER JOIN table2 ON table1.date = table2.date
UNION
SELECT table2.date, other_stuff
FROM table1
RIGHT OUTER JOIN table2
ON table1.date = table2.date
";
$result = mysqli_query( $con, $query );
while( $record = mysqli_fetch_array( $result ) ){
echo '<html table generated based on query>';
}
Example
This is an schematic diagram of FULL OUTER JOIN concept:
After running into quite a few bumps with this one, I finally managed to merge 2 columns from each table and also to use where and sort clauses on them with the following query:
( SELECT user_visit_logs.user_id,user_visit_logs.date,unique_hits,non_unique_hits,earned,sites_surfed,earnings FROM user_visit_logs
LEFT OUTER JOIN surfer_stats ON user_visit_logs.user_id = surfer_stats.user_id AND user_visit_logs.date = surfer_stats.date where user_visit_logs.user_id = 23 ORDER BY date DESC LIMIT 30 )
UNION
( SELECT surfer_stats.user_id,surfer_stats.date,unique_hits,non_unique_hits,earned,sites_surfed,earnings FROM user_visit_logs
RIGHT OUTER JOIN surfer_stats ON user_visit_logs.user_id = surfer_stats.user_id AND user_visit_logs.date = surfer_stats.date where user_visit_logs.user_id = 23 LIMIT 30 )
Simplified, "user_visit_logs" and "surfer_stats" were the 2 tables needed to be joined.
Absolutely. Just pop them both into a variable:
$data = '';
$query = mysqli_query($con,"SELECT date, stuff* ");
while($record = mysqli_fetch_array($query)) {
$data.= '<tr><td>--Your Row Data Here--</td></tr>';
}
$query2 = mysqli_query($con,"SELECT date, other stuff*");
while($record = mysqli_fetch_array($query2)) {
$data .= '<tr><td>--Your Row Data Here--</td></tr>';
}
echo "<table>$data</table>";
Instead of using echo in your loop, you're just storing the results in $data. Then, you're echoing it out after all data has been added to it.
As for your second point, it's not a big deal if fields don't exist. If they're null, you'll just have a column that doesn't have data in it.
Here's an example with fake column names:
$data = '';
$query = mysqli_query($con,"SELECT date, stuff* ");
while($record = mysqli_fetch_array($query)) {
$data.= "<tr><td>{$record[id]}</td><td>{$record[first_name]}</td><td>{$record[last_name]}</td></tr>";
}
$query2 = mysqli_query($con,"SELECT date, other stuff*");
while($record = mysqli_fetch_array($query2)) {
$data .= "<tr><td>{$record[id]}</td><td>{$record[first_name]}</td><td>{$record[last_name]}</td></tr>";
}
echo "<table><tr><th>ID</th><th>First Name</th><th>Last Name</th></tr>$data</table>";
I have a feeling I may have misunderstood the need. If so, I apologize. If you can elaborate just a bit more I can change my answer :)
I'm running a second database search using mysql inside a for loop but I can't get it show the correct amount of rows:
Original search:
$topicemailsql = "select se.id as id, se.users as users, se.topic as topic, se.body as body, se.postID as postID, DATE_FORMAT(se.sent, '%d.%m.%Y %H:%i:%s' ) as sent, (SELECT u.email from users u where u.users_id in (se.users)) as emails from sentEmail se LEFT OUTER JOIN topics t on (t.ID = se.theader_) where t.ID = '$topicID'";
$topicemailsqlquery = mysql_query($topicemailsql)or die(mysql_error());
$numrows = mysql_num_rows($topicemailsqlquery);
php for loop:
for ($i=0; $i < $numrows ; $i++){
$sqlarray = mysql_fetch_array($topicemailsqlquery);
$users = $sqlarray['users'];
$sqlemail = ('select email from users where users_id in ("'.$users.'")');
//echo $sqlemail;
$emailsqlquery = mysql_query($sqlemail)or die(mysql_error());
$amountofusers = mysql_num_rows($emailsqlquery);
$sqlarrayemail = mysql_fetch_array($emailsqlquery);
echo $amountofusers;
//echo $sqlarrayemail['email'];
for ($a=0; $a < $amountofusers ; $a++){
if($a == 0){
$email = $sqlarrayemail['email'];
}
else if($a < $amountofusers){
$email = $sqlarrayemail['email'].','.$sqlarrayemail['email'];
}
}
}
So based on this the $amountofusers should return more than 1 row but now it always return only one row.
When I echo the $sqlemail it should return 2 rows because it looks like this:
select email from users where users_id in ("4,82") --> this should return 2 rows and a count of 2 but it only returns one row.
Where does it go wrong?
Br,
Toby
I think, it's a very bad idea to store multiple values in one field. Furthermore I wouldn't fire up queries in a loop, if I can avoid it. Better fetch the data in one go and let PHP do the rest. If you try your query i.e. with PHPAdmin you would use
SELECT email
FROM users
WHERE users_id IN (4, 82)
The IN operator needs a comma separated list of arguments. You give one single value
"4,82"
That's a huge difference. MySQL would accept ("4","82") too (other DBMS are not as tolerant) and handle the not needed conversion for you.
Hello I would like to query multiple identical tables in my db which has different prefixes and than display the results randomly but somehow I need to track the origin of the item and I couldn't figure out how
I do the query like this because I don't have access to information_schema
$query = "SHOW TABLES FROM mydb WHERE RIGHT( tables_in_mydb, 5 ) = 'table'";
$res = mysql_query($query);
$num = mysql_num_rows($res);
while($row = mysql_fetch_row($res)) {
$numbers = explode('_', $row[0]);
if($num > 0) {
$q = "SELECT `this`, `that`, `something` FROM ".$numbers[0]."_idetinticaltables"; // :)
$r = mysql_query($q);
while($c = mysql_fetch_array($r)) {
/*display the results randomly with an identifier where the come from*/
}
}
}
You could use ORDER BY RAND() to randomly sort it
The following might work:
Get the list of the tables you're interested in. You already do that.
Create a UNION of multiple SELECT statements. Each SELECT statement differs for the table being selected from and you add a column set to the name of the table (so you can identify it later):
(SELECT *, TABLENAME = 'first_name_of_table' FROM first_name_of_table ...)
UNION
(SELECT *, TABLENAME = 'second_name_of_table' FROM second_name_of_table ...)
UNION
...
ORDER BY RAND() LIMIT 10;
Because it is a UNION you can randomize the whole order then. See How can i optimize MySQL's ORDER BY RAND() function? because it is not that trivial to do well, the example above is only to have an ORDER BY and LIMIT clause placed there. With many entries in your tables, it will kill your server.
$aa=array()
while($c = mysql_fetch_array($r))
{
/*display the results randomly with an identifier where the come from*/
$aa[]=$c;
}
echo $aa; // print "Array"
Trying to search through a column in a db, and pull out the total number of males, and total number of females.
This data is stored in the db as f and m in the whatsex column.
$query = "SELECT whatsex, COUNT(*) FROM soberdata GROUP BY whatsex";
$result = mysqli_query($connection,$query) or die(mysql_error());
$sexdb = mysqli_fetch_array($result);
$totalmale = $sexdb['m'];
$totalfemale = $sexdb['f'];
echo $totalfemale." & ".$totalmale;
This code outputs nothing. What am I doing wrong?
$sexdb have only "whatsex" and "COUNT(*)" columns. You should use one of them
try
print_r($sexdb);
and look if some of results meet your needs
Your query is going to return a whatsex value, and a COUNT(*) value, not m or f. Doing a var_dump($sexdb) would show you what's in the array.
You are treating a multi-dimensional array as flat. You could do this to flatten it
$query = "SELECT whatsex, COUNT(*) as total FROM soberdata GROUP BY whatsex";
while ($row = mysqli_fetch_array($result)) {
$$row['whatsex'] = $row['total']; // this makes a variable ($m or $f) using the value of the row
}
$totalmale = !empty($m) ? $m : 0;
$totalfemale = !empty($f) ? $f : 0;
You should empty check the results of the db in case there is no male or female entries to avoid errors.