How to get variables from MySQL Query (multiple level array)? - php

I have the following:
$sql = "SELECT c.category_name
, c.category_name_url
FROM blog_categories AS c
JOIN blog_articles AS a
ON a.category_name = c.category_name
WHERE c.category_status = 'online'
GROUP BY c.category_name
";
$result = mysql_query($query) or die(mysql_error());
while($row = mysql_fetch_array($result)) {
$category_name = $row['c']['category_name'];
$category_name_url = $row['c']['category_name_url'];
}
But it's not working (generating blanks). I'm sure I'm doing something wrong, but I don't know what the formal terms of what I'm looking for is so Google is no help =/.

code was not running because you dint supply a valid resource for the mysql_fetch_array.
also $row will be a single dimensional array.
$sql = mysql_query("SELECT c.category_name
, c.category_name_url
FROM blog_categories AS c
JOIN blog_articles AS a
ON a.category_name = c.category_name
WHERE c.category_status = 'online'
GROUP BY c.category_name
");
while($row = mysql_fetch_array($sql)) {
$category_name = $row['category_name'];
$category_name_url = $row['category_name_url'];
}

$category_name = $row['category_name'];
Well, I vote for PDO, but I am pretty sure you can skip the 'c', as $row will refer to the fieldname. The c is just evaluated by the DBMS to associate the field with the propper table.

You should call mysql_query on your $sql (the sql query), you then call mysql_fetch_array againts the result of the call. Anyway, you should almost always call mysql_error to check for errors.

Related

Get values from different tables inside a while loop statement using php

I'm having an issue of retrieving values from two different tables. Here's the code so far:
$result = mysqli_query($conn,"SELECT * FROM articles");
$num = mysqli_num_rows($result);
while ($row = mysqli_fetch_array($result)) {
$uid=$row['_uid'];
$result2 = mysqli_query($conn, "SELECT _username FROM users WHERE _id = '$uid' ";
$num2 = mysqli_num_rows($result2);
while ($row2 = mysqli_fetch_array($result2)) {
$username = $row2['_username'];
}
$divtext='<h3>'.$row['_posttype'].'</h3> <h2>'.$username.' </h2>';
}
I've been reading that I should preform this while inside a while with multiple query, also found on w3 that you could directly assign a value to a variable directly using:
"SELECT _username INTO $username FROM users WHERE _id = '$uid' LIMIT 1";
But this works in SQL inside myadmin, in a php I can't find how to cast it.
I have also replace the fetch_row for fetch_assoc and still nothing, im struggling for two days already with this.
you could select al the value using a single query
SELECT a._uid , a._posttype, u._username
FROM articles a
INNER JOIN users u on a._uid = u._id
..
$result = mysqli_query($conn,
"SELECT a._uid , a._posttype, u._username
FROM articles a
INNER JOIN users u on a._uid = u._id");
$num = mysqli_num_rows($result);
while ($row = mysqli_fetch_array($result)) {
$divtext='<h3>'.$row['_posttype'].'</h3> <h2>'.$username.' </h2>';
}
$echo $divtext;

Putting data from two different loops in a google pie chart

So I have this code for my Google pie chart (pie chart code not included, but it works fine and displays data)
<?php
$query = "SELECT * FROM category WHERE type = 'Expense' ";
$select_category_list = mysqli_query($connection, $query);
while($row = mysqli_fetch_assoc($select_category_list)) {
$cat_id = $row['id'];
$cat_title = $row['title'];
echo "['$cat_title'" . ",";
echo "$cat_id],";
}
?>
I put the echo in different lines, but it really does not matter to if they are in one line or in two lines, what matters is to get it finally working :)
Instead of $cat_id I want to put the SUM ($cat_amount) calculated by this code:
$query = "SELECT category_id, SUM(amount) AS TotalAmount FROM spendee
WHERE type = 'Expense' group by category_id ";
$expense_query = mysqli_query($connection, $query);
while ($row = mysqli_fetch_assoc($expense_query)) {
$cat_amount = $row['TotalAmount'];
}
I have tried putting while loop in a while loop, foreach loop in a while loop, putting $cat_amount instead of $cat_id (that only displays one SUM) and so on. Nothing worked. I have not tried the for loop, but I assume the result would be the same + I am not sure how would I define the times that the loop needs to run, since there could be many type 'Expense' categories added in time.
Any help would be very much appreciated. Thank you and have a lovely day.
maybe i'm missing something, but looks like you could join the two tables in one query
this would get the desired result in one query / loop...
sql:
SELECT a.title as Title, SUM(b.amount) AS TotalAmount FROM category a, spendee b WHERE b.category_id = a.id and b.type = 'Expense' group by a.title
php:
<?php
$query = "SELECT a.title as Title, SUM(b.amount) AS TotalAmount FROM category a, spendee b WHERE b.category_id = a.id and b.type = 'Expense' group by a.title";
$select_category_list = mysqli_query($connection, $query);
while ($row = mysqli_fetch_assoc($select_category_list)) {
$cat_title = $row['Title'];
$cat_amount = $row['TotalAmount'];
echo "['$cat_title'" . ",";
echo "$cat_amount],";
}
?>

Looping through a mysqli result

I'm trying to display a list of status updates from artists that a logged in user is following.
So far I have this:
#Get the list of artists that the user has liked
$q = "SELECT * FROM artist_likes WHERE user_id = '1' ";
$r = mysqli_query($dbc,$q);
while ($row = mysqli_fetch_array($r, MYSQLI_ASSOC)) {
#Now grab the statuses for each artist
$status_query = "SELECT * FROM status_updates WHERE artist_id = '".$row['artist_id']."' ";
$status_result = mysqli_query($dbc,$status_query)
}
But i'm not sure how to loop through and display the returned status updates?
This isn't a strong point of mine, so any pointers would be greatly appreciated!
What prevented you from doing similar to what you'd already done for the first query? Something like follows:
#Get the list of artists that the user has liked
$q = "SELECT * FROM artist_likes WHERE user_id = '1' ";
$r = mysqli_query($dbc,$q);
while ($row = mysqli_fetch_array($r, MYSQLI_ASSOC)) {
#Now grab the statuses for each artist
$status_query = "SELECT * FROM status_updates WHERE artist_id = '".$row['artist_id']."' ";
$status_result = mysqli_query($dbc,$status_query)
while($status_result_row = mysqli_fetch_assoc($status_result)) {
echo $status_result_row['mycol']; // This is where you know better than us
}
}
Or if those two tables artist_likes and status_updates have artist_id in common then you could just use one query with a join. (But don't know if you are asking for that).
Just for avoiding multiple query, you can use one query like this:
SELECT l.*, s.*
from artist_likes l, status_updates s
WHERE
l.artist_id = s.artist_id and
l.user_id = '1'
or
SELECT l.*, s.*
from artist_likes l
JOIN status_updates s on (l.artist_id = s.artist_id)
WHERE
l.user_id = '1'

How to Get another value in another table using a dynamic call

I currently have this query with an array that outputs the variables within using a dynamic input in my form (term), this creates a Dynamic Search with auto complete to fill in all of the details for a product.
$return_arr = array();
$param = $_GET["term"];
$fetch = mysql_query("SELECT * FROM crd_jshopping_products WHERE `name_en-GB` REGEXP '^$param'");
while ($row = mysql_fetch_array($fetch, MYSQL_ASSOC)) {
//$row_array['category_id'] = $row ['category_id'];
$row_array['product_id'] = $row['product_id'];
$row_array['product_names'] = $row['name_en-GB'];
$row_array['jshop_code_prod'] = $row['product_ean'];
$row_array['_ext_price_html'] = number_format($row['product_price'],2);
if (!empty($row['product_thumb_image']) AND isset($row['product_thumb_image'])){
$row_array['image'] = $row['product_thumb_image'];
}else {
$row_array['image'] = 'noimage.gif';
}
array_push( $return_arr, $row_array);
}
mysql_close($conn);
echo json_encode($return_arr);
Unfortunately I also need to get the category_id which is not in the same table, I have tried to modify my query as such, but to no avail:
$fetch = mysql_query("SELECT * FROM crd_jshopping_products WHERE `name_en-GB` REGEXP '^$param' AND `crd_jshopping_products_to_categories` = `product_id` ");
What step am I missing here ? The product_id's match in both tables?
try this query instead and try to understand what I have written in it:
$fetch = mysql_query("
SELECT
p.*,
c.category_id
FROM
crd_jshopping_products as p
INNER JOIN crd_jshopping_products_to_categories as c
ON p.product_id = c.product_id
WHERE
`p.name_en-GB` REGEXP '^$param'
");
This means:
SELECT:
Give me everything from p and the category_id from c.
FROM:
Do this from rows in the tables crd_jshopping_products (referred to as p) and crd_jshopping_products_to_categories (referred to as c), where the rows match on the count of p.product_id is the same as c.product_id.
WHERE:
Only return the rows where p.name_en-GB REGEXP '^$param'.

select row where the slot is the biggest

i need to select one row where slot_left is the biggest. i tried
for ( $i=1;$i<3;$i++) {
$sql5 = "SELECT * from user u where (
select max(slot_left) from company c,user u
where c.id=u.company_id and c.id='$name'
)";
$result5 = mysqli_query($link, $sql5) or die(mysqli_error($link));
while($row=mysqli_fetch_array($result5)) {
// echo the id which the slot_left is the biggest
echo $i['slot_left'];
}
}
but still cannot. please help!
You have to use GROUP BY in your query.
And query execution in Loop is not recommended, it will decrees performance.
Try this.
$sql5 = "select c.id, max(slot_left) from company c,user u
where c.id=u.company_id and c.id='$id' GROUP by c.id";
$result5 = mysqli_query($link, $sql5) or die(mysqli_error($link));
while($row=mysqli_fetch_array($result5)) {
echo $row['slot_left'];
}
SQL can be. You select all rows from DB.
$sql5 = "select max(slot_left) AS slot_left from company c,user u where c.id=u.company_id and c.id='$name' GROUP by u.company_id";
$name variable used in query not set
Variable $i is not array. Array is $row
echo $row['slot_left'];

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