Using php if...else statement with two queries - php

I have two queries that count the number of data for both "artists" and "groups" in my database. I want to display a message if there is data to display for either artists or groups (or both), and if the data returns 0 for both of them then not to display anything.
I have the following code which doesn't seem to work:
<?php if (($numrowsartists==0)OR($numrowsgroups==0)) {
} else {
echo "There is information to display.";
}
?>
Below are the queries I have:
$query = "SELECT COUNT(*) FROM `Credit_To_Artist` AS c2a
INNER JOIN `Credits` AS cr ON cr.credit_id = c2a.credit_id
INNER JOIN `Artist` AS a ON a.artist_id = c2a.artist_id
WHERE c2a.song_id = $id";
$res = mysql_query($query);
$numrowsartists = mysql_fetch_assoc($res);
$query = "SELECT COUNT(*) FROM `Credit_To_Artist` AS c2a
INNER JOIN `Credits` AS cr ON cr.credit_id = c2a.credit_id
INNER JOIN `Artist_Group` AS ag ON ag.group_id = c2a.group_id
WHERE c2a.song_id = $id
ORDER BY ag.group_name ASC";
$res = mysql_query($query);
$numrowsgroups = mysql_fetch_assoc($res);
Thanks in advance. I'm sure it's probably a super basic fix but I'm still very new to php and would appreciate some help.

You should getthe value frorm the row eg using alias for column name
$query = "SELECT COUNT(*) as num_artists FROM `Credit_To_Artist` AS c2a
INNER JOIN `Credits` AS cr ON cr.credit_id = c2a.credit_id
INNER JOIN `Artist` AS a ON a.artist_id = c2a.artist_id
WHERE c2a.song_id = $id";
$res = mysql_query($query);
$row = mysql_fetch_assoc($res);
$numrowsartists = row['num_artists'];
$query = "SELECT COUNT(*) as num_groups FROM `Credit_To_Artist` AS c2a
INNER JOIN `Credits` AS cr ON cr.credit_id = c2a.credit_id
INNER JOIN `Artist_Group` AS ag ON ag.group_id = c2a.group_id
WHERE c2a.song_id = $id
ORDER BY ag.group_name ASC";
$res = mysql_query($query);
$row = mysql_fetch_assoc($res);
$numrowsgroups = row['num_groups'];

There are several solutions, the easiest being the following:
if($numrowsartists[0]+$numrowsgroups[0] > 0)
However, as people have said, you shouldn't use mysql_* functions anymore.
Assuming the ID is user input, you should really use prepared statements.
Also, you can handle both tests in a single query:
$stmt = $con->mysqli_prepare("SELECT COUNT(1) as `count` FROM `Credit_To_Artist` AS c2a
INNER JOIN `Credits` AS cr ON cr.credit_id = c2a.credit_id
INNER JOIN `Artist` AS a ON a.artist_id = c2a.artist_id
INNER JOIN `Artist_Group` AS ag ON ag.group_id = c2a.group_id
WHERE c2a.song_id = ?");
$stmt->bind_param('i',$id);
$stmt->execute();
if($stmt->get_result()->fetch_array()[0] > 0){
...
}else{
//message that nothing was found
}

Related

How to create IF statement in MYSQL query WHERE statement

Is this possible to be done with SQL?
I need to make a SQL selection depending if a $query is false WHERE (u.id_user = ".$userId." OR fu.id_user = ".$userId." OR ff.id_user = ".$userId.")" ELSE "$query";
That's my starting point where both conditions have to be met:
$validatedSearchData = array(
"q"=>strip_tags($_GET["q"])
);
$query= " AND a.tags LIKE ".lib::$db->qstr("%".$validatedSearchData["q"]."%");
$feed = lib::$db->GetAll("SELECT SQL_CALC_FOUND_ROWS
a.*,
u.name,
fu.id_user AS fu_user_id,
ff.id_followed_user AS ff_user_id
FROM feed AS a
LEFT JOIN userfollow AS fu ON a.id_author = fu.id_user
LEFT JOIN userfollow AS ff ON a.id_author = ff.id_followed_user
INNER JOIN user_profiles AS u ON a.id_author = u.id_user
WHERE (u.id_user = ".$userId." OR fu.id_user = ".$userId." OR ff.id_user = ".$userId.")" . $query. "
GROUP BY a.id_article
");
Change this line
$query= " OR a.tags LIKE ".lib::$db->qstr("%".$validatedSearchData["q"]."%");
replace OR in the place of AND

Twice a where in a survey

Instead of wanting the whole table i only want one result based on a link.
This works:
$BANDID = intval($_GET['BANDID']);
$sql = "SELECT
BANDID,
NAAMBAND,
CONTACTBAND,
GENRE,
OMSCHRIJVING,
LEDEN,
PLAATS,
PRIJS,
BOEKERID,
WEBSITE,
YOUTUBE,
NOTITIES
FROM
`BANDS`
WHERE
BANDID = $BANDID";
$BANDID is get by clicking a link on a previous page, but i wanted it combined the above
$sql = "SELECT
NAAM,
BANDID,
NAAMBAND,
CONTACTBAND,
BOEKERID
FROM
`BANDS`
INNER JOIN
`adres`
WHERE
`BANDS`.BOEKERID = `adres`.id ";
but this doenst work:
$BANDID = intval($_GET['BANDID']);
$sql1 = "SELECT
NAAM,
BANDID,
NAAMBAND,
CONTACTBAND,
BOEKERID
FROM
`BANDS`
INNER JOIN
`adres`
WHERE
`BANDS`.BOEKERID = `adres`.id
WHERE
BANDID = $BANDID";
Please help me further, thks
You should use ON and combine it with WHERE like this:
$sql1 = "SELECT NAAM,BANDID, NAAMBAND, CONTACTBAND, BOEKERID
FROM `BANDS` INNER JOIN `adres`
ON `BANDS`.BOEKERID = `adres`.id
WHERE BANDID=$BANDID";
That's how you do proper joins.
WHERE `BANDS`.BOEKERID = `adres`.id WHERE BANDID=$BANDID";
replace second where with AND
WHERE `BANDS`.BOEKERID = `adres`.id AND BANDID=$BANDID";
You need to change to proper join syntax. Every join needs an ON clause and then you can put your WHERE clause below that.
$sql1 = "SELECT NAAM,BANDID, NAAMBAND, CONTACTBAND, BOEKERID
FROM `BANDS`
INNER JOIN `adres`
ON`BANDS`.BOEKERID = `adres`.id
WHERE BANDID=$BANDID";

MYSQLI SELECT with Limit not working

I'm trying to find the number of rows in a table in the database depending on certain conditions with a limit feature so that i can count the number of rows there are matching the condition after a certain row in the table.
Thus i created my php query:
$q = $db->query("SELECT u.*, f.* FROM updates U LEFT JOIN friends f ON f.fid = u.userid WHERE f.uid = '$userid' ORDER BY u.up_id DESC LIMIT $limitID, 9999999");
$nr = $q->num_rows;
However even if there are more rows in the database after the $limitID, it says there are no rows.
If I try this:
$q = $db->query("SELECT u.*, f.* FROM updates U LEFT JOIN friends f ON f.fid = u.userid WHERE f.uid = '$userid' ORDER BY u.up_id DESC LIMIT $limitID");
$nr = $q->num_rows;
then it works, but it doesnt count after the $limitID. Any udeas?
According yo your query, it should be like
$sql = "SELECT count(*) FROM updates U
LEFT JOIN friends f ON f.fid = u.userid WHERE f.uid = ?";
// getting stuff using prepared statements
$row = $res->fetch_row();
$num = $row[0] - $limitID;
but I doubt it's really what you need either.
Using what Your Common Sense told me I managed to find an answer to my problem, so here it is:
$limitID = $upid;
$sql = "SELECT count(*) FROM updates u
LEFT JOIN friends f ON f.fid = u.userid WHERE
(f.uid = '$userid' AND u.up_id > '$limitID')";
$res = $db->query($sql);
$row = $res->fetch_row();
$num = $row[0];
if($num == 0){
// do nothing
} else {
echo "<span class='newPosts'>" .$num. " New Post"
. (($num>1)?'s':' ') . "</span>";
}
works perfectly

Sort the results of a query using results of another query

Im working on a message board of some sort and i have everything up an running except one little part, the threads need to be sorted by the date/time of the latest post in them (standard forum format), which im having lots of trouble wrapping my head around.
This is the querys im using, i know its not pretty and its not safe, i will be reworking them once i learn how to do it properly.
$sql = "SELECT Thread_ID, Thread_Title, Board_ID, Author FROM threads WHERE Board_ID='$Board_ID' LIMIT $offset, $rowsperpage";
$result = mysql_query($sql, $conn) or trigger_error("SQL", E_USER_ERROR);
while ($row = mysql_fetch_assoc($result))
{
$Thread_ID = $row['Thread_ID'];
$Thread_Title = $row['Thread_Title'];
$Board_ID = $row['Board_ID'];
$Author = $row['Author'];
$getauthor = mysql_query("SELECT * FROM members WHERE Member_ID='$Author'");
while ($row = mysql_fetch_assoc($getauthor))
{
$Post_Author = $row['Post_As']; }
$postcount = mysql_query("SELECT Post_ID FROM posts WHERE Thread_ID='$Thread_ID'");
$Posts = mysql_num_rows($postcount);
$getlatest = mysql_query("SELECT * FROM posts WHERE Thread_ID='$Thread_ID' ORDER by Post_DateTime DESC LIMIT 1");
while ($row = mysql_fetch_assoc($getlatest))
{
$Post_DateTime = time_ago($row['Post_DateTime']);
$Member_ID = $row['Member_ID']; }
$getmember = mysql_query("SELECT * FROM members WHERE Member_ID='$Member_ID'");
while ($row = mysql_fetch_assoc($getmember))
{
$Post_As = $row['Post_As']; }
So what im trying to do is Sort $sql by $getlatest, i tried adding another query above $sql that did basically the same as $getlatest and then had $sql order by that but alas it just broke everything.
I know i have to make a variable to sort the $sql by but its that variable thats driving me mad.
any help would be appreciated, thanks.
current error message as requested:
Fatal error: SQL - Unknown column 'posts2.LatestPost' in 'on clause' - SELECT threads.Thread_ID, threads.Thread_Title, threads.Board_ID, threads.Author, Sub1.LatestPost, Sub1.PostCount, members.Post_As, members2.Member_ID AS LastPostMemberID, members2.Post_As AS LastPostMemberPostAs FROM threads INNER JOIN (SELECT Thread_ID, MAX(posts.Post_DateTime) AS LatestPost, COUNT(*) AS PostCount FROM posts GROUP BY Thread_ID) Sub1 ON threads.Thread_ID = Sub1.Thread_ID INNER JOIN members ON threads.Author = members.Member_ID INNER JOIN posts posts2 ON posts2.Thread_ID = Sub1.Thread_ID AND posts2.LatestPost INNER JOIN members members2 ON members2.Member_ID = posts2.Member_ID WHERE threads.Board_ID='1' ORDER BY Sub1.LatestPost DESC LIMIT 0, 25 in C:\wamp\www\forum\include\threads.php on line 86
You should be able to do it using something like this for your first query:-
$sql = "SELECT threads.Thread_ID, threads.Thread_Title, threads.Board_ID, threads.Author, MAX(posts.Post_DateTime) AS LatestPost
FROM threads
LEFT OUTER JOIN posts ON threads.Thread_ID = posts.Thread_ID
WHERE threads.Board_ID='$Board_ID'
GROUP BY SELECT threads.Thread_ID, threads.Thread_Title, threads.Board_ID, threads.Author
ORDER BY LatestPost DESC
LIMIT $offset, $rowsperpage";
EDIT
Not tested the following but looking at your selects I think you could probably put it together into a single SELECT. Something like this:-
$sql = "SELECT threads.Thread_ID, threads.Thread_Title, threads.Board_ID, threads.Author, Sub1.LatestPost, Sub1.PostCount, members.Post_As, members2.Member_ID AS LastPostMemberID, members2.Post_As AS LastPostMemberPostAs
FROM threads
INNER JOIN (SELECT Thread_ID, MAX(posts.Post_DateTime) AS LatestPost, COUNT(*) AS PostCount FROM posts GROUP BY Thread_ID) Sub1
ON threads.Thread_ID = Sub1.Thread_ID
INNER JOIN members
ON threads.Author = members.Member_ID
INNER JOIN posts posts2
ON posts2.Thread_ID = Sub1.Thread_ID AND posts2.Post_DateTime = Sub1.LatestPost
INNER JOIN members members2
ON members2.Member_ID = posts2.Member_ID
WHERE threads.Board_ID='$Board_ID'
ORDER BY Sub1.LatestPost DESC
LIMIT $offset, $rowsperpage";
$result = mysql_query($sql, $conn) or trigger_error("SQL", E_USER_ERROR);
while ($row = mysql_fetch_assoc($result))
{
$Thread_ID = $row['Thread_ID'];
$Thread_Title = $row['Thread_Title'];
$Board_ID = $row['Board_ID'];
$Author = $row['Author'];
$Post_Author = $row['Post_As'];
$Posts = $row['PostCount'];
$Post_DateTime = time_ago($row['LatestPost']);
$Member_ID = $row['LastPostMemberID'];
$Post_As = $row['LastPostMemberPostAs'];

PHP MySQL query help

I am trying to use this query to return every instance where the variable $d['userID'] is equal to the User ID in a separate table, and then echo the username tied to that user ID.
Here's what I have so far:
$uid = $d['userID'];
$result = mysql_query("SELECT u.username
FROM users u
LEFT JOIN comments c
ON c.userID = u.id
WHERE u.id = $uid;")$row = mysql_fetch_assoc($result);
echo $row['username'];
This should work
$uid = mysql_real_escape_string($d['userID']);
$result = mysql_query("SELECT u.username
FROM users u
LEFT JOIN
comments c
ON c.userID = u.id
WHERE u.id = '$uid'");
while($row = mysql_fetch_assoc($result))
{
//PRINTS ALL INSTANCES OF THE ROW
echo $row['username'];
}
what is printed from the echo above.
if you're looking to get all the results. wrap your mysql_fetch_assoc in a while loop:
$result = mysql_query("SELECT u.username
FROM users u
LEFT JOIN comments c
ON c.userID = u.id
WHERE u.id = $uid;");
while($row = mysql_fetch_assoc($result)){
echo $row['username'];
}
Try this:
$uid = $d['userID'];
$result = mysql_query("SELECT u.username
FROM users u
LEFT JOIN comments c
ON c.userID = u.id
WHERE u.id = $uid");
while($row = mysql_fetch_assoc($result))
{
echo $row['username'];
}
*EDIT:*Removed semicolon.

Categories