bring data from 2 tables mysql and display them - php

I have 2 tables. Table user_job(id, title, expires) and table user_job_business(id, title, expires). The first table holds jobs posted by users and the second table holds jobs posted by companies. All I want is to display all jobs from users and companies in the same page the one under the other each job in its own table. How can I modify my code to do this? This is my code dipslaying jobs from users one under the other.
<?php
$get_myjobs = mysql_query("select * from `user_job` ");
while($run_job = mysql_fetch_array($get_myjobs )){
$user_job_id = $run_job['id'];
$user_job_title = $run_job['title'];
$user_job_expires = $run_job['expires'];
echo"<table> <td>$user_job_title</td> <td>$user_job_expires</td> </table>";
}
?>

you can use union or union all:
$get_myjobs = mysql_query("select id, title, expires from `user_job` union all select id, title, expires from `user_job_business`");
the difference between union and union all, union remove redundancy or repeated rows.

You can use union in your case, but I would recommend you reorganize your structure and make 1 table instead of 2. It will give you better schema and good performance.
it | title | expires | role_id
where role_id - identifier to user,company

Related

What join to use

I have two tables, one for registered users and one to store votes.
We are logging in with registrants.id and registrants.zipcode. Once they vote their votes are inserted into the votes table, along with their Registration ID.
Im trying to right a select statement that returns a record that will select all the records for Matched ID and Zipcode, but the ID is not in the Votes.voter column. i have tried all kinds of variations of all the joins i can think of. is it something simple i am missing.
SELECT * FROM registrants
LEFT JOIN votes on registrants.id = votes.voter
WHERE registrants.id = 1 AND registrants.zipcode = 46706 and votes.voter <> 1
Perhaps a not exists query:
select * from registrants
where registrants.zipcode = '46706'
and not exists (select 1 from votes where registrants.id = votes.voter)

Slow queries with MySQL large database

I have a table ipaddresses that contains IP ranges. Columns are: ipStart, ipEnd
Example of
ipStart: 3579374832
ipEnd: 3579374839
Now I want to select 300ish IP addresses from another table: visit_count. And based on those 300 addresses I want to check if the ip address is in the range of any of IPs in the table ipaddresses
My current code:
$results = $database->query("SELECT user_id,
DATE_FORMAT(last_visit, '%Y-%m-%d') as datumet,
cookieId, ipaddress
FROM `visit_count`
WHERE last_visit BETWEEN
'$firstDayOfMonth' AND '$lastDayOfMonth'
AND user_id = '$userId'
GROUP BY cookieId
ORDER BY last_visit ASC");
$rows = $database->loadObjectList($results);
foreach ( $rows as $row ) {
$ipaddressLong = ip2long($row->ipaddress);
// This is where its very very slow
$selO = $database->query("SELECT ipStart, ipEnd FROM `ipaddresses`
WHERE '$ipaddressLong' BETWEEN `ipStart` AND `ipEnd`");
$rowO = $database->getrow($selO);
}
The result is a really slow query that consumes a lot of cpu.
ipaddresses has indexes for both ipStart and ipEnd and contains around 50k rows.
How can I make this go faster?
A quick and dirty change to a single query using a JOIN:-
SELECT a.ipStart, a.ipEnd
FROM `ipaddresses` a
INNER JOIN
(
SELECT user_id, DATE_FORMAT(last_visit, '%Y-%m-%d') as datumet, cookieId, inet_aton(ipaddress ) AS ipaddressLong
FROM `visit_count`
WHERE last_visit BETWEEN '$firstDayOfMonth' AND '$lastDayOfMonth'
AND user_id = '$userId'
GROUP BY cookieId
) b
ON b.ipaddressLong BETWEEN a.ipStart AND a.ipEnd
Note that this could probably be simplified. However it depends on your use of GROUP BY cookieId . At the moment this is going to get one row per cookie id, but which row is undefined (ie, could be any user_id, ip address and last visit date that goes with that cookie id).
You can simplify the first select. You don't need to select any fields beyond ipaddress. You also don't need to order or group the result. If you want unique ipaddresses, just use distinct
select distinct ipaddress
from visit_count
where last_visit between '$firstDayOfMonth' and '$lastDayOfMonth'
and user_id = '$userId'
300 selects don't seem to be much, even with the second table having 50k rows. On my machine, even without indexes, it takes only a fraction of a second.
If you want to simplify it anyway, you can join the two tables with
select ipstart, ipend
from ipaddresses i
join visit_count v on inet_aton(v.ipaddress) between i.ipstart and i.ipend
where v.last_visit between '$firstDayOfMonth' and '$lastDayOfMonth'
and v.userid = '$userId'
1) Use better query like other suggested to you
2) Have you defined indexes for the field you need ?
3) Dont know if you use mysql or mysqli...anyway use fetch_assoc that is faster then fetch_array
with this 3 trick you should be ok

SELECT * FROM tbl WHERE col1=$var1 and col2=$var2 and col3=$var3

Music Database Site:
I have a table named ps_albums with columns: artist, album, genre_id, and so on.
I also have a second table named ps_users with the following column: user_id, date_joined, fave_genre_1, fave_genre_2, fav_genre_3 and other.
My overall goal is to display only the genres of music that a user selects for the top 3 favorite selections.
I am able to INSERT the genre_id of all 3 favorite genre selections into ps_profiles which hold this info. Now I need to be able to pull the 3 genres_id's and display only them instead off all genres by default.
So by default SELECT * FROM ps_albums ORDER by DESC;
Thus displaying ALL albums on the front page.
Now, when that user clicks 'My Favorite Genres' I do this...
$query= "SELECT * FROM `ps_profiles` WHERE `user_id`= $user_id";
$row = #mysql_fetch_object(#mysql_query($query));
$genre1 = $row->fav_genre_1;
$genre2 = $row->fav_genre_2;
$genre3 = $row->fav_genre_3;
I want to be able to display all records from ps_albums according to the 3 favorite selections from ps_profiles.
How would I setup the select statement?
SELECT * FROM ps_albums WHERE genre=$genre1 AND genre=$genre2 AND genre=$genre3
How would I go about this? There are more then 10 genres but I only want to show the ones selected as favorites from the 3 columns. Hopes this clarifys a bit more.
SELECT * FROM ps_albums WHERE genre in ($genre1,$genre2,$genre3)
You could use either OR's or IN() to match a column value with multiple possible value.
For example:
SELECT * FROM t WHERE a=1 OR a=2 OR a=3;
SELECT * FROM t WHERE a IN(1,2,3);
So for your case, it could look something like this:
$query = "SELECT * FROM ps_albums WHERE genre IN('$genre1', '$genre2', '$genre3')";
I added quotes in the query, I'm assuming genre's are strings?

A complicated mysql join

Ok, I have this first table which has, among other things:
table 1: id | depID (every id has one depID)
Then, I have a second table where I have table 2: userID | depID (where an userID is associated with multiple depIDs in separate rows. Also, I have table 3 with userID | rankID (where an userID is associated with one rankID).
I need to get all id and depID from table 1, and then to check, which userIDs of table 2 shares the same depID (table1.depID = table2.depID), and then, to check which of those userIDs from table 2 has rankID = $rID
Thanks guys.
I think this SQL should get you what you want, but I'm not 100% clear from the wording of the question:
SELECT table2.userID
FROM table1
JOIN table2
ON table1.depID = table2.depID
JOIN table3
ON table2.userID = table3.userID
AND table3.rankID = $rID;

Join tables - MySQL & PHP

I'm trying to join two tables. The first table has a list of 11 items which are 'site_names' with an auto id field of 'id'. The second table that I want to connect has an auto id field of 'desc_id' and another field of 'descriptions'. This second table currently has 3 rows of data that I want displayed only for id 1 in table 1.
So, I want to accomplish is to connect the first site in table one with an id of '1' to the entire second table.
I can't seem to figure out how connect only the first entry(id=1) in table 1 to all the rows in table 2 (tb.1->id->1 to tbl.2->desc_id->1,2,3).
I hope that made sense. Any help would be great. Thanks
Try:
select site_name, descriptions
from table_1
inner join table_2
on 1 = 1
where table_1.site_id = 1
This should join give you what you want.
OK - based on the comment, I'm guessing what you want is:
site1 | desc1 | desc2 | desc3
all on one row. This is a bit trickier - particularly if you want it to remain open to an arbitrary number of descriptions. For just 3 (or, really, any limited subset, but as the number goes up, it gets ugly), you could do:
select site_name, t2.desc, t3.desc, t4.desc
from table_1
inner join table_2 t2
on t2.desc_id = 1
inner join table_2 t3
on t3.desc_id = 2
inner join table_2 t4
on t4.desc_id = 3
where site_id = 1
This kind of stuff is highly irregular though. It seems to me like something about your schema is probably not quite right to generate this sort of requirement.
Here is the query:
<?php
$mysql = new mysqli('localhost', 'root', 'root') or die('counld not connect');
$result = $mysql->query("SELECT ajax_demo.explore.site_name, anthony1.property.descriptions FROM ajax_demo.explore INNER JOIN anthony1.property ON ajax_demo.explore.id = anthony1.property.desc_id") or die($mysql->error);
if($result)
{
while($row = $result->fetch_object())
{
$id = $row->id;
$siteName = $row->site_name;
$siteDescription = $row->site_description;
echo "$siteName";
echo "$siteDescription";
}
}
?>
I may be missing something here, but it sounds to me like you need to add a foreign key to the Site table. If I understand your question correctly, your tables should look something like this:
Site
- SiteID
- DescriptionID
- SiteName
Description
- DescriptionID
- Description
Then your query to get Sites and their associated Descriptions would look like this:
SELECT
s.SiteName,
d.Description
FROM
Site s INNER JOIN Description d
ON s.DescriptionID = d.DescriptionID
This table structure assumes that multiple Sites share single Descriptions (as per your posted question).

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