How to retrieve data from multiple tables using a PHP form? - php

I want to retrieve data from multiple tables using dot operator/join where arguments are passed from an HTML/PHP form.
HTML CODE
<input name="rollno" type="text" placeholder="Roll Number" required>
<input name="submit_view_details" type="submit" value="Proceed">
PHP CODE
if(isset($_POST['submit_view_details']))
{
$rollno = (int) $_POST['rollno'];
$query = "select * from table1, table2 where table1.{$rollno}=table2.{$rollno}";
$result=mysqli_query($connection,$query);
}
In the browser if enter the input 1 and echo this query then it looks like follows:
select * from table1, table2 where table1.1=table2.1
and no row is fetched despite of having data in the table(s).
it only works if the query looks like follows:
select * from table1,table2 where table1.rollno=table2.rollno
However, in that case it fetches all the rows but I need only the row of the rollno that user entered in the above mentioned form.
I am just not able to work this out. Help would be much appreciated. Thanks!

Use the AND keyword to specify the rollno.
SELECT * FROM table1, table2 WHERE table1.rollno = table2.rollno
AND table1.rollno = {$rollno};
You could probably use the keyword JOIN instead like this :
SELECT * FROM table1 NATURAL JOIN table2
WHERE rollno = {$rollno};

You need joins
take a reference of joins from here,
i am sure it will help
http://www.tutorialspoint.com/mysql/mysql-using-joins.htm

You should use join like this
$query = "SELECT tbl1.*, tbl2.*
FROM tbl1
INNER JOIN tbl2 ON tbl1.id = tbl2.id
WHERE tbl1.column = value ";

foreach ($pieces_2 AS $value) {
$pieces_3[] ="(CONCAT_WS('|',$presql2) like '%$value%')"; //concat all columns from one table
}
$serch_jyouken = implode(" and ",$pieces_3); // for multiple keywords
$result1 = mysqli_query($connection, "select p.p_no from pfr_data p where (" .$serch_jyouken .")");
$res1 = array();
while($r1 = mysqli_fetch_array($result1){
$res1[] = $r1['p_no'] ; //fetch primary key from table and store it into array
}
foreach ($pieces_2 AS $value) {
$pieces_4[] ="(CONCAT_WS('|',$presql3) like '%$value%')"; // same as above
}
$serch_jyouken1 = implode(" and ",$pieces_4);
$result2 = mysqli_query($connection, "select p2.p_no from pfr_mod_inform p2 where (" .$serch_jyouken1 .")" );
$res2 = array();
while($r2 = mysqli_fetch_array($result2)){
$res2[] = $r2['p_no'];
}
$res_mrg = array_merge($res1 , $res2); //merge array
$result = implode("','",$res_mrg ); // array to sring
$sql5 = $presql ." from pfr_data p where p.p_no in ('$result') order by p.section_p,p.status,p.no";

Related

1 JSON object, 2 queries, 2 tables

Here is my simple query:
$sql = "SELECT * FROM donations Order By userid";
$result = $mysqli->query($sql);
while($row = $result->fetch_assoc()){
$json[] = $row;
}
$data['data'] = $json;
I use it to display all data from the 'donations' in a table. Fields are: userid,date,amount.
In that same table, I'd like to add firstname and lastname of corresponding userid which are stored in mymembers table. The condition should be WHERE donations.userid = mymembers.id.
I need help adding that condition for every row resulting from the $sql query.
Use join and change query to
SELECT * FROM donations
INNER JOIN mymembers on (donations.userid = mymembers.id)
Order By donations.userid

Select multiple rows from table using checkboxes

I'm trying to use checkboxes for multiple sql query with SELECT.
I have 3 tables, one table for groups one for users and one to connect the user to different groups called groupreluser. Based on what groups are checked, I want it to print out the phonenumber of each user that are a member of those groups.
The checkboxes are created based on the content of the table groups
<form method="post">
<?php
$sql = "SELECT * FROM groups WHERE groupname LIKE '%minor%'";
$result = $conn->query($sql);
if($result->num_rows > 0){
while($row = $result->fetch_assoc()){
echo '<input type="checkbox" name="checked[]" value="'.$row['group_id'].'">'
. $row['groupname'] . '</br>';
}
}
?>
<input type="submit" name="submit" value="submit">
</form>
Code with the sql query to get the phonenumbers.
if(isset($_POST['submit'])){
$check = $_POST['checked'];
if(!empty($check)){
foreach($check as $sel){
$sel = mysqli_real_escape_string($conn, $sel);
$sql = "
SELECT
groups.group_id,
groups.groupname,
groupreluser.user_id,
groupreluser.group_id,
users.user_id,
users.name,
users.phone
FROM
groupreluser
JOIN
groups
ON
groups.group_id = groupreluser.group_id
JOIN
users
ON
users.user_id = groupreluser.user_id
WHERE
groups.group_id = '$sel'
";
$res = $conn->query($sql);
if($res->num_rows > 0){
while($row = $res->fetch_assoc()){
echo $row['phone'] . '</br>';
}
}
}
}
}
It works fine as long as I dont use the checkboxes but adds the group_id manually in the SELECT statement. Any idea of why this isn't working? Am I missing someting? Dont know if this is the best way to do it though...
Let me know if this is unclear, and I'll try to explain it better
This line probably doesn't work:
$check = mysqli_real_escape_string($conn, $_POST['checked']);
$_POST['checked'] is an array. So you have do the line above for each item in the array.
Your $_POST['submit'] is array so directly passing it to mysqli_real_escape_string won't work. But this approach will do the work:
if(isset($_POST['submit'])){
$check = $_POST['check'];
if(!empty($check)){
foreach($check as $sel) {
$sel = mysqli_real_escape_string($conn, $sel);
$sql = "
SELECT
groups.group_id,
groups.groupname,
groupreluser.user_id,
groupreluser.group_id,
users.user_id,
users.name,
users.phone
FROM
groupreluser
JOIN
groups
ON
groups.group_id = groupreluser.group_id
JOIN
users
ON
users.user_id = groupreluser.user_id
WHERE
groups.group_id = '$sel'
";
$res = $conn->query($sql);
...........

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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