I have two tables...
Table 1 (keywordsTbl)
KeyID Key_Name
================================
1 Biology
2 Entertainment
Table 2 (profileTbl)
Keyword_ID Key_Name
================================
1(from keywordsTbl) Biology(from keywordsTbl)
2(from keywordsTbl) Entertainment(from keywordsTbl)
My query in profileTbl is indexing KeyID from the keywordsTbl and its working fine. The only problem is my output shows up like so (no array). :
Seems like its indexing only the 1st keyID... The results only show 1 single keyword even though there are more than one keyID being placed in the row:
My query looks as so:
include 'db.php';
$sql = mysqli_query($con,"SELECT * FROM profileTable, addKeywordTable ORDER BY LaName ASC");
while ($row = mysqli_fetch_array($sql))
{
$fname = $row['FirName'];
$lname = $row['LaName'];
$title = $row['Title'];
$keys = $row['Keyword_Name'];
$id = $row['source_ID'];
if(!in_array($title,array('',null)) && !empty($title)):
$title = '('.$title.')';
else:
$title = '';
endif;
What's the easiest way to show an array when two tables are being used? Would a join work better in this case?
I am not 100% sure that this is what you are asking, but if you want a list of results based on a join for KeyID you can do something like this:
SELECT p.Laname, p.FiName, GROUP_CONCAT(k.Key_Name)
FROM ProfileTable AS p
JOIN addKeywordTable AS k ON k.KeyID = p.Keyword_ID
GROUP BY p.LaName, p.FiName
If you want to include more files in the select list you need to add them to the GROUP BY list or use an aggregate function (GROUP_CONCAT, MAX, MIN, etc) on them in the select list.
Related
I have two different tables of the following structure:
grouprel
id | userId | pupID | groupId
pupils
id | userId | fname | lname
pupId in groulrel is equal to id in pupils.
I want to fetch pupils from a different group and then order them by fname, lname.
Now I have two queries like this:
$q = "SELECT * FROM grouprel WHERE userid = ". $userid ." AND groupId = ". $_GET['id'] ."";
$r = mysqli_query($mysqli, $q);
while ($rows = mysqli_fetch_object($r)) {
$query = "SELECT id, fname, lname FROM pupils WHERE userid = ". $userid ." AND id = ". $rows->pupId ." AND status = 0 ORDER BY fname, lname";
$result = mysqli_query($mysqli, $query);
while($row = mysqli_fetch_object($result)) {
echo stuff...
}
}
This works, but it doesn't order the names alphabetically like I want to.
How could I fix this?
This is iterating over the first query:
while ($rows = mysqli_fetch_object($r)) {
And this iterates over each instance of the second query:
while($row = mysqli_fetch_object($result)) {
So if the first query returns 1,2,3, and each iteration of the second query returns A,B, then your output would be:
1 A
1 B
2 A
2 B
3 A
3 B
The second query is ordering by the ORDER BY clause you gave it. But you are ordering the entire output by the first query.
Ultimately, why do you need these separate queries at all? Executing a database query in a loop is almost always the wrong idea. It looks like all you need is one query with a simple JOIN. Guessing on your logic, something like this:
SELECT
pupils.id, pupils.fname, pupils.lname
FROM
pupils
INNER JOIN grouprel ON pupils.id = grouprel.pupId
WHERE
pupils.userid = ?
AND grouprel.groupId = ?
AND pupils.status = 0
ORDER BY
fname, lname
It may take a little tweaking to match exactly what you're looking for, but you can achieve your goal with a single query instead of multiple separate queries. Then the results of that query will be ordered the way you told MySQL to order them, instead of the way you told PHP to order them.
Namastey!
I'm currently working on one of my projects where I get to one doubt.
What I'm doing is:
I have got 4 tables called:
1: project_degree
2: project_department
3: project_category
4: Projects
project_degree have got four top level degrees which are: B.tech, M.tech, M.C.A. & M.B.A.
project_department have got their respective departments such as: C.S.E, I.T., E.E.E. and so on.
Now, project_category have some categories like PHP, .NET, SAP etc.
What I'm trying to do is, I'm adding a project to database called "projects" where I'm assigning it to its degree, department and category.
Structure of projects table is as follows:
id | project name | degree_id | Dept_id | Cat_id
1 | Sample project | 1 | 3 | 4,3,6,5,9
Now as you can see above, field "cat_id" have got multiple categories where each categories ID have been separated by a comma.
Now when I call a query get all projects from the table called "projects", I want to list of categories related to that particular project and my code goes like this:
$query = mysql_query("SELECT * from projects ORDER BY id DESC");
while($row = mysql_fetch_array($query)) {
$categories = $row['cat_id'];
$cat_arr = explode(',',$categories);
$cat_size = sizeof($cat_arr);
for($i=0;$i<$cat_size;$i++) {
$get_cat = mysql_query("SELECT * from project_category WHERE id='".$cat_arr['$i']."'");
$cat_row = mysql_fetch_array($get_cat);
echo $cat_row['name']; // Here finally I'm getting categories name
}
}
So, finally I'm running nested loop and two queries to get a category name. I doubt it affect the page load time when it comes to huge data.
Is there any better alternative to this situation?
Here should be work
$query = mysql_query("SELECT * from projects ORDER BY id DESC");
while($row = mysql_fetch_array($query)) {
$get_cat = mysql_query("SELECT * from project_category WHERE id IN (" . $row['cat_id'] . ")");
$cat_row = mysql_fetch_array($get_cat);
echo $cat_row['name']; // Here finally I'm getting categories name
}
But normalization is better.
It's better to add a new table, project_has_catID where you can store project.id and cat.id as two columns (project_id and cat_id). Remove the Cat_id column in the project table.
Once done, simply select the name by the next query;
$query = mysql_query("SELECT project_category.name from project_category INNER JOIN project_has_catID phc ON phc.cat_id = project_category.id ORDER BY phc.project_id DESC");
By this, you have a list of category names. You don't have to loop with multiple database communications.
You could load all category names into an associative array first, then look up category names in this array when looping through the projects.
$categoryNames = array();
$query = mysql_query("SELECT id, name FROM project_category");
while ($row = mysql_fetch_array($query))
{
$categoryNames[$row['id']] = $row['name'];
}
$query = mysql_query("SELECT * FROM projects ORDER BY id DESC");
while ($row = mysql_fetch_array($query))
{
$categoryIds = explode(',', $row['cat_id']);
foreach ($categoryIds as $cat_id)
{
$cat_name = $categoryNames[$cat_id];
//do what you want with the name here
}
}
This way, you don't have to change your database structure, or the structure of your code. And you only have to execute two queries in total, so this is by far the simplest solution.
Needless to say, normalization is always better as others have indicated (never use a column that contains multiple comma-separated values), but you probably knew that and had your reasons for setting up your database tables this way.
My code right now is this
$extract = mysqli_query($dbc, "SELECT * FROM items");
$numrows = mysqli_num_rows($extract);
while($row = mysqli_fetch_assoc($extract)) {
$id = $row['i_id'];
$iname = $row['i_name'];
echo "<tr><td><a href='capture.php?item_id=$id'>$iname</a></td><td>Incomplete</td></tr>";
}
What i want to do is run a check to see if the item has already been completed.
I have a separate table that contains the information, for instance say that Item 1 has been completed then I would like to be able to change my echo to something like:
echo "<tr><td>$iname</td><td>Complete!</td></tr>";
How would I accomplish this? Would I need to use some form of a join statement?
I want to be able to display all the items in the table but not duplicate them i initially thought that an if statement on the echo to see if item complete then do this else do that
Here are the two tables
Items item_collection
------ ---------------
i_id i_id
i_name complete
caption
image
c_id
g_id
You can use join condition like this (assuming complete is a varchar field)
SELECT a.i_id, a.i_name,
CASE WHEN i_status = '1' THEN 'Complete!' ELSE 'Incomplete' END AS complete_status
FROM items a
LEFT OUTER JOIN item_collection b ON a.i_id = b.i_id
select
case
when ic.complete = 1 then 'Complete'
else 'Incomplete'
end as item_status
from items i
left join item_collection ic on i.i_id = ic.i_id
where i.i_name = 'your_item_name'
Assuming that ic.complete = 1 when item is complete.
Something along the lines of SELECT * FROM table1 WHERE table1.id not in (SELECT Id FROM table2)
I've got
a users table named "members"
a rooms table named "rooms"
a table that associates the user id to the ids of the rooms "membersRooms"
I should write a loop that prints a dropdown for each user with all the rooms, but that adds the attribute "selected" to rooms associated with the user
What's wrong with this loop?
$members = mysql_query("SELECT * FROM members ");
$rooms = mysql_query("SELECT * FROM rooms");
while($member = mysql_fetch_array($members)){
echo("<select>");
$roomsOfUser = mysql_query("SELECT roomID FROM membersRooms WHERE userID=".$member["id"]);
$cuArray = mysql_fetch_array($roomsOfUser);
while($room = mysql_fetch_array($rooms)){
if(in_array($room["id"],$cuArray,true))
echo("<option selected='selected'>".$room["roomName"]."</option>");
else
echo("<option>".$class["roomName"]."</option>");
}
echo("</select>");
}
To make this a little easier on you, you could try utilizing left and right joins on your database. This would significantly reduce your server load and still allow you to do the same functionality.
I believe, if I'm reading your database structure right, that you'ld want something along the lines of:
SELECT members.id as memberID, rooms.id as roomID, rooms.roomName, membersRooms.roomID as memberRoom
FROM members
LEFT JOIN membersRooms
ON members.id = membersRooms.userID
RIGHT JOIN rooms
ON membersRooms.roomID = rooms.id
Then in PHP you should be able to just keep track of when your memberID changes, and when it does, start a new select. If I didn't totally bungle that SQL (which I might have) then the resulting rows should look something like:
memberID | roomID | roomName | memberRoom
1 1 foo 1
1 2 bar 1
2 1 foo 1
2 2 bar 1
So on your loop iteration you would use roomID and roomName to build your select, and if RoomID matched memberRoom then you would select that row.
$rooms query while is dead
while runs once time in while
put this $rooms = mysql_query("SELECT * FROM rooms"); query line
in first while
OK, so you need information from 3 tables - members, rooms, and membersRooms. The rows from members and membersRooms line up 1:1, so we can get both of those with 1 query.
This method will minimize the number of queries needed - if you ever see yourself querying the database in a loop, ask yourself if there's a better way.
$member_query = mysql_query("SELECT * FROM members LEFT JOIN membersRooms ON (members.id = membersRooms.userID)");
$room_query = mysql_query("SELECT * FROM rooms");
$rooms = array();
while ($room = mysql_fetch_assoc($room_query))
$rooms[] = $room;
while ($member = mysql_fetch_assoc($member_query)) {
echo '<select>';
foreach($rooms as $room) {
echo "<option value='{$room['roomID']}' ";
if ($member['roomID'] == $room['id'])
echo 'selected="selected"';
echo ">{$room['roomName']}</option>";
}
echo '</select>';
}
It's worth noting that if members:rooms is a 1:many relation, you don't need to use a third table to join them - just add a roomId to members, and you're fine.
I am looking for a cleaner way to do this. My code works, but I know it can be better. I have three tables: one with a list of Category Groups, One with a list of categories that are linked to category groups, and one with a list of news stories that are linked to the categories.
I need to loop through all of the names of the Category Groups, followed by the names of the categories that are in the category groups, with the number of news stories in each category listed as well.
I have three tables: CategoryGroups, Categories, News.
I have a set of queries. The first queries all the rows from the CategoryGroups table:
$result = mysql_query( '
SELECT cat_group_id, cat_group_name FROM CategoryGroups
' );
The second query is inside the looped results of the first query and finds all the categories that have a news item and are linked to a specific category group:
<?php
while( $row = mysql_fetch_assoc( $result ) ){
$id = $row['cat_group_id'];
$name = $row['cat_group_name'];
echo "<h3>$name</h3>";
$sql = mysql_query("
SELECT category_id, title FROM `Categories`
WHERE cat_group_id = $id
AND category_id IN
(SELECT news.category_id FROM news)
");
while( $row = mysql_fetch_assoc($sql) ) {
$title = $row['title'];
$catid = $row['category_id'];
$numbers = mysql_query("
SELECT * FROM news
WHERE category_id =$catid"
);
$nums = mysql_num_rows($numbers);
echo "$title ($nums)<br/>\n";
}
?>
I would like to limit this to one or two queries, with efficiency in mind. I know this can be done, however I have not been successful in my attempts.
thanks.
Why not JOIN the tables?
SELECT cat_group_name, title, count(newsid)
FROM CatagoryGroups
INNER JOIN Categories ON cat_group_id
INNER JOIN News ON category_id
GROUP BY cat_group_name, title
looks like it should be close, if table news has a newsid column (it's gotta have SOME primary key, right? well, count that;-). With the obvious indexes the JOINs should be quite fast, and your PHP code can do whatever output formatting you may need from that.
I suggest you need to get a book on SQL, such as "SQL Queries for Mere Mortals."
$sql = mysql_query("
SELECT cg.cat_group_name, c.title, COUNT(n.category_id) AS NumNews
FROM `CategoryGroups` cg
JOIN `Categories` c USING (cat_group_id)
JOIN `News` n USING (category_id)
GROUP BY cg.cat_group_name, c.title");
Then loop over the result and output a new <h3> each time the cat_group_name is different from the previous row.