I have a table...
Table: forums
for_id for_name for_des for_mem
1 Forum 1 Description 1 mem1#email.com, mem2#email.com
2 Forum 2 Description 2 null
3 Forum 3 Description 3 mem1#email.com
Then i have another table: members
mem_id mem_name mem_email ...
1 Jane mem1#email.com
2 Jack mem2#email.com
3 Smith mem3#email.com
I am trying to create an HTML Options list. A multi select list that would display all columns in members and then select those in a forums when editing the information.
Example: Editing for_id = 1
It should display all users and select only users who are in for_id=1's for_mem
Currently i am using:
<? $data = explode(',',$row[for_mem]); ?>
<div class="col-md-9">
<select name="for_mem" id="" multiple class="form-control">
<?php foreach($data as $key => $value){?>
<option value="<?php echo $value; ?>"><?php echo $value; ?></option>
<?php } ?>
</select>
</div>
But it only displays the users in the for_mem for that Forum, not all users for them to select new ones to add. Also, just the email. Is there a way to display the name?
Please help. Thanks
This query can solve partly & then join both by union. first part is members that are exist in forums and second part members that are not exist for the forums.
I have added a field "checked" which is 1 for first part and 0 for second part used for identified which users to checked when display.
select for_id, for_name, for_mem, mem_name, mem_email, 1 checked from forums, members where locate(mem_email, for_mem) > 0
union
select for_id, for_name, for_mem, mem_name, mem_email, 0 checked from forums, members where locate(mem_email, for_mem) = 0;
may be there any syntactically mistake i haven't tested because of data unavailable. You can use group by or group concat for more. I advice to run it on mysql prompt first and see the result and modify as your need.
Related
A user puts in their information via a scroll down menu and selects an option a couple of times. When they do this, it is saved as a INT rather then a STRING. This is because some calculations need to be run on the informaton. So essentially it looks like this:
<select name="option1">
<option value="0">Chair</option>
<option value="10">Table</option>
<option value="20">Counter</option>
<option value="30">Toaster</option>
<option value="40">Oven</option>
<option value="50">Microwave</option>
</select>
<select name="option2">
<option value="0">Red</option>
<option value="2">Blue</option>
<option value="4">Green</option>
<option value="6">Yellow</option>
<option value="8">Orange</option>
These values are added together to make a sum. So a blue(2) table(10) would have a value of 12.
My problem arises when I want users to be able to edit this data. I want to display the data they currently have, however it is now saved as a INT. How would I make it so that the information is displayed back in text format based on a the value in the database. (ie. a value of 38 would output "Orange Toaster)?
*I am doing this in PHP but I am not necassarily looking for code, just an idea on how to do this.
You can save the options in database with the following table structure.
Table Name: selection_options
id(pk) option_name option_value category
1 chair 0 option1
2 Table 10 option1
3 Toaster 30 option1
.
.
6 red 0 option2
7 Orange 8 option2
.
.
so on
For creating the selection box option1 execute the query as below:
$option1Array = "SELECT * FROM selection_options WHERE category = 'option1'" ;
This will give you all the options available in the category option1
Do same for the option2 now your selection boxes will be changed as below:
<select name="option1">
<?php foreach($option1Array as $option1) {?>
<option value="<?php echo $option1['id']; ?>"><?php echo $option1['option_name']; ?></option>
<?php }?>
</select>
<select name="option2">
<?php foreach($option2Array as $option2) { ?>
<option value="<?php echo $option2['id']; ?>"><?php echo $option2['option_name']; ?></option>
<?php } ?>
</select>
Now you have to save this data in the database as below:
Table Name: users_selected_options
id user_id option1 option2
1 1 3 7
.
.
id: Primary key of the table
user_id: Foreign key of the user table
option1: Foreign key of the selection_options
option2: Foreign key of the selection_options
No you want to show what options user has selected fire a execute join query you will get the result.
SELECT uso . * , so.option_name, so1.option_name, (so.option_value + so1.option_value) AS total
FROM users_selected_options AS uso
JOIN selection_options AS so ON uso.option1 = so.id
JOIN selection_options AS so1 ON uso.option2 = so1.id
WHERE user_id =1
LIMIT 0 , 30
The above query will give you the records as below:
id user_id option1 option2 option_name option_name total
1 1 3 4 Toaster Orange 38
So now you can easily iterate over the result and show the appropriate output to the user.
This solution is might be lengthy for you but it will helps in future when you want to make the
application dynamic as.
Now you can easily provide the interface to add / edit the values
and options names.
2.If the option names and values are being changed
you don't have to worry about as we are getting the SUM directly by
the query.
3.Now you can able to save the multiple data against the
same user.
4.In future if you want to provide option3 for the
selection then you can do this change easily and you just have to
update the query not in the entire code.
To start you will need to find the remainder when divided by 10.
if($numberX%10 == 4) { echo "Green"; }
You need a table to save all of the options eg:
id info
-- ----
0 Red Chair
2 Blue Chair
...
But I might be better saved in 2 tables, why do you sum them up as one int?
OK since you said no need to add them up, try two tables:
id furniture
-- -------
10 ...
id color
-- -----
2 Blue
For non-table solution, you save above values into an array eg
$furniture = array(
10 => '...',
...
);
$colors = array(
2 => 'Blue',
...
);
It is not a good idea to make some ID value as 0
You can use math functions.
Use division that you can find remainder which would be your option2 and use subtraction (integer - remainder) = your option1
Okay i'm going to attempt to reword the question that was put on hold. I have a table in my database called anime this is what it looks like:
the code below mainly focuses on the tags row in the database which will has tags listed like this: tag1, tag2, tag3 etc..
I am trying to make a search that works via selecting keywords (tags) from a dropdown options menu (well 3 dropdown menus) since all the keywords (tags) are fixed and the tags within the database are fixed (the same) i can use
$tag_x = "tag1";
$tag_y = "";
$tag_z = "";
$tag_search = "%(?=.*$tag_x)(?=.*$tag_y)(?=.*$tag_z)%";
// Connect to Database
require 'connect.php';
$sql = "SELECT id, title, category FROM anime";
$result = $conn->query($sql);
if ($result->num_rows > 0)
{
// output data of each row
while ($row = $result->fetch_assoc())
{
$tags = $row["category"];
if (preg_match($tag_search, $tags)) {
echo $row["id"];
}
}
}
else
{
echo "0 results";
}
$conn->close();
this code can show matches for 1 - 3 keywords (tags)
the problem is i don't think this is a great way to do it and also i need to run it three times to get a list of results that have 3 matches first then 2 matches then 1 tag match, in a list.
////// OLD QUESTION BELOW THAT WAS PUT ON HOLD. (not sure if i should delete.) ///////////
Hello I am new to mysqli and databases in general I have been trying to find a way to filter down SELECT queries and display the results.
I have a database with lists of items that all have related tags and I am trying to show the row(s) and their information when a user makes a search query (via drop down menus). The data looks like this:
ID NAME TAGS CAT IMG_FILE_NAME
1 demo one tag1, tag2, tag3 ... something.png
2 demo two tag2, tag4 ... something.png
3 demo three tag0 ... something.png
4 demo four tag3, tag4, tag5 ... something.png
5 demo five ... ... something.png
6 ... ... ... ...
the search will work like this
<label for="x">I am looking for:</label>
<select id="x">
<option value="t1">Tag 1</option>
<option value="t2">Tag 2</option>
<option value="t3">Tag 3</option>
</select>
<label for="y">That has:</label>
<select id="y">
<option value="t4">Tag 4</option>
<option value="t5">Tag 5</option>
<option value="t6">Tag 6</option>
</select>
<label for="z">and is:</label>
<select id="z">
<option value="t7">Tag 7</option>
<option value="t8">Tag 8</option>
<option value="t9">Tag 9</option>
</select>
and the user may select x = tag 2 y = tag 5 z = tag 8
and then hit search or go and it would pull/show the results from the database with the tags the selected and failing that show the ones with the next closest matching tags (2 tags then 1 tag etc..)
can the WHERE statement do this?
I think 90% of my problem with finding an answer to this question is how i'm wording the question in the first place but after 3+ hours looking for something that works and not finding anything this seems like the best place to ask once again! any help would be amazing! and code/links to code would be greatly apperated!
The comma-separated values in your TAGS column are sub-optimal. You can, possibly, make this work like so
SELECT NAME, CAT, IMG_FILE_NAME
FROM item
WHERE TAGS LIKE CONCAT('%', ?tag1, '%')
AND TAGS LIKE CONCAT('%', ?tag2, '%')
AND TAGS LIKE CONCAT('%', ?tag3, '%')
where ?tag1 etc are the values provided by your user. But this sort of wildcard matching (WHERE TAGS LIKE '%tag3%', for example) is both error-prone and horribly slow if your table is large. (If your user gives you less than three tags, you need to use less than three WHERE clauses.
Do you want this to work well? Put the tags in their own tag table, with columns like so:
item_id
tag
So, if you item with id = 2 has tag2 and tag4, you'll have two rows in the tag table
2 tag2
2 tag4
Then, you can search with queries like this
SELECT COUNT(*) MATCHES, i.NAME, i.CAT, i.IMG_FILE_NAME
FROM tag t
JOIN item i ON t.item_id = i.id
WHERE t.tag = ?tag1
OR t.tag = ?tag2
OR t.tag = ?tag3
GROUP BY i.NAME, i.CAT, i.IMG_FILE_NAME
ORDER BY COUNT(*) DESC, i.NAME
This will give you a list of the items that match any or all the tags your user specified, with the ones that match more tags listed first.
yes, you should write something like:
SELECT field_a, field_b FROM table WHERE field_x='2' AND field_y='5' AND field_z='8'
it is obvious that you have to adapt it to your table and to your field names but can give you a hint.
Based on your comment you should do something like:
SELECT field_a, field_b FROM table WHERE tags='2, 5, 8'
but note that this will look for the exact string. So if you have a row where tag = '5,2,8' (same tags but different order) you will not get the result.
It is better (IMHO) to use three columns like tag_1, tag_2 and tag_3 and store each value in a single column? So that my first example will become
SELECT field_a, field_b FROM table WHERE tag_1='2' AND tag_2='5' AND tag_3='8'
I have three tables (I simplified it in this question) :
Table 1
id | Name
-----------
1 | John
2 | Smith
Table 2
id | Title
-----------
1 | Developer
2 | Web Developer
3 | A New Title
Table 3 (links between 1 and 2)
idName | idTitle
-----------
1 | 1
1 | 2
2 | 1
My problem is with the update page. My HTML is <select multiple> ... options ... </select> and I am using chosen to select and deselect options. I am trying to do this with PHP only.
Lets say that we have the following scenario:
The administrator wanted to remove the 'Developer' Title for 'John' and add 'New Title' for 'John'.
He/She will deselect Title id 1 and select id 3. When He/She submits the form I will get two select values: id 1 (the one that he selected) and id 2 (the one that was already there). But I will not get id 3 because he deselected it.
What I am struggling with is : when the user posted the new selected values the ones that were deselected were not submitted with the form. There is no way for me to track the ones that were deselected so I can delete them from my table. How do you update your table with the new changes then? Do you delete what is already existed in that table and add the ids again? Is there a better option?
UPDATE :
It seems #wander answer is less destructive than the other ones. However, #wonder did not explain how to compute step 4 in his answer. to distinguesh between new selected options, already existing selected options, and deselected options.
There's no need to submit the deselected one. e.g.
John has two titles(Developer and Web Developer) saved in database.
The administrator opens the page, selects 'New Title', deselects 'Developer' and clicks submit.
Now on server side, we can get
the title list of John stored in database: Developer and Web Developer
title list submitted from the users: Web Developer and New Title
We compare the two title lists and figure out: we shall delete Developer title and add New Title on John.
You could add hidden fields before the select menu which will cause 0/falsey values to also be sent to PHP.
<input type="hidden" name="stuff[]" value="0" />
<input type="hidden" name="stuff[]" value="0" />
<input type="hidden" name="stuff[]" value="0" />
<select multiple name="stuff[]">
<option value="1">1</option>
<option value="2">2</option>
<option value="3">3</option>
</select>
This is similar to how you would send unchecked check boxes to the server:
https://stackoverflow.com/a/1992745/268074 (note the answer without JS)
You can dump your old values in a hidden select, so you'll get them when handling your form.
<!-- Invisible select field -->
<select multiple name="oldData[]" style="display:none;" aria-hidden="true">
<option value="1">1</option>
<option value="2" selected>2</option>
<option value="3" selected>3</option>
</select>
<!-- Real select field -->
<select multiple name="data[]">
<option value="1">1</option>
<option value="2">2</option>
<option value="3">3</option>
</select>
Note: I was inspired by #Petah's answer, don't forget to upvote him :-).
Let's say we have $old_titles list with titles from db, and $new_titles titles from submit.
$add = array_diff($new_titles, $old_titles);
$delete = array_diff($old_titles, $new_titles);
$add - list of titles to add, $delete - list of titles to delete.
Add action:
$dbh->prepare('INSERT INTO table3(idName, idTitle) VALUES (:idName, :idTitle)');
foreach($add as $titleId) {
$dbh->execute(['idName' => $userId, 'idTitle' => $titleId]);
}
Delete action:
$dbh->prepare('DELETE FROM table3 WHERE idName = :idName AND idTitle = :idTitle');
foreach($delete as $titleId) {
$dbh->execute(['idName' => $userId, 'idTitle' => $titleId]);
}
Not sure why everybody keeps using hidden input fields to track the existing data. When you POST your form, you can just retrieve the original values from the database. That's a lot safer then depending on user input, because even hidden fields can be altered. I know it won't matter too much in this particular situation, but I think it's best to always use the best practise.
Now in PHP you have two options. The first would be to delete all relations and then add the new relations. The second would be to delete all that wasn't posted and add/update the relations that where.
Although the second options might seem to be the "least destructive" as you call it, it is the easiest and least error prone way. The only reason I would abandon this tactic is when I would store extra data in the relations table. EG: date added (when did somebody get into a function) or added by user.
How would you go about it (method 2)?
Keep in mind that I use a method that tries to continue whenever possible. Another approach would be to halt when false data is posted.
<?php
if (array_key_exists("relations",$_POST) && is_array($_POST["relations"])) {
//no duplicates, you dont want to store the same function twice
//only integers
$list = array_unique(array_filter($_POST["relations"], "is_int"));
$csv = implode(',', $list);
//get the userid hoewever you normally would
$userId = 1
//Delete existing
$query = "DELETE FROM Table3 WHERE idname=".$userId
//insert all posted functions
//I select the id's from the actual table so it will never inserted a none existing ID.
//this approach never has duplicates, so the duplicate check in the beginning is redundant now, but I leave it incase I change this.
$query = "INSERT INTO Table3 (idName, idTitle) SELECT ".$userId.", Id FROM Table2 WHERE id IN (".$csv.")".
//execute queries
} else {
//nothing posted, delete all relations
}
?>
Now if you only want to insert new data and remove none-existing
<?php
if (array_key_exists("relations",$_POST) && is_array($_POST["relations"])) {
//no duplicates, you dont want to store the same function twice
//only integers
$list = array_unique(array_filter($_POST["relations"], "is_int"));
$csv = implode(',', $list);
//get the userid hoewever you normally would
$userId = 1
//Delete existing
$query = "DELETE FROM Table3 WHERE idname=".$userId." AND idTitle NOT IN (".$csv.")"
//only insert new functions
//I select the id's from the actual table so it will never inserted a none existing ID.
//this approach never has duplicates, so the duplicate check in the beginning is redundant now, but I leave it incase I change this.
$query = "INSERT INTO Table3 (idName, idTitle) SELECT ".$userId.", Id FROM Table2 WHERE id IN (".$csv.") AND id NOT IN (SELECT idTitle FROM table3 WHERE idName=".$userId.")".
//execute queries
} else {
//nothing posted, delete all relations
}
?>
The only better way is the simplest one, remember KIS
on update you just need to do following
DELETE FROM table3 WHERE idName=??
and then insert all selected idTitles again in table3
This can be done in two SQL statement without knowing which value has been de-selected. Following these 2 steps
1) In your PHP, create a comma separated list of all selected option. For example: 2, 3.
2) Then execute the following statements:
DELETE FROM tblLink WHERE idName = $id AND idTitle NOT IN ($list);
INSERT IGNORE tblLink (idName, idTitle)
SELECT $id, id FROM tblTitle WHERE id IN ($list);
Note: for shake of simplification, I use $id and $list in my example. When you intent to use it, you should properly prepare and bind parameter properly. Make sure that idName and idTitle are primary key to make it work.
To my opinion you have to check what actions should be performed first. This is a small example that you can run here http://sandbox.onlinephpfunctions.com/code/0fa11b3c9f846e344c912f5a3e994eea5e9cac34.
First run a select on Table 3 for idName=1 the output would be an array of idTitle's (1,2). In the following example the $array1 is the output of such a select statement and $array2 is the array of new idTitle's for the same idName that will have to be updated or deleted or inserted. If for example the new idTitles for a user are more or less than the previous ones then there you should have some sort of control over it in order to decide what queries you will run to the database.
$array1 = array(1,7,3,5);// initial idTitles try it on the above link (php sandbox) with more or less values
$array2 = array(1,4,3,6);//new idTitles try it on the above link (php sandbox) with more or less values
$count1=count($array1);
$count2=count($array2);
$diff=$count1-$count2;
if ($diff==0) {
$result1=array_values(array_diff_assoc($array2,$array1));
$result2=array_values(array_diff_assoc($array1,$array2));
$countr=count($result1);// or $result2 it is the same since they have the same length
$cr=0;
while($cr < $countr) {
print_r("update tblname set val=$result1[$cr] where id=theid and val=$result2[$cr]\n");
$cr++;
}
}
if ($diff!=0) {
$result1=array_diff($array2,$array1);
$result2=array_diff($array1,$array2);
if(count($result2)>0) {
foreach($result2 as $r2) {
print_r("delete from tblname where id=theid and val=$r2\n");
}
}
foreach($result1 as $r1) {
print_r("insert into tblname where id=theid and val=$r1\n");
}
}
How I would do it would extend the 1st table
id | Name | Title IDs
1 | John | 1,2
2 | Smith | 1,3
Each time the row is updated I would simply just replace the title_ids fields and be done with it.
After registering at my site, I want the user to select some elements from a table that already exists in my DB, and add them to "their" column in another table.
Say this is the existing table in a MySQL DB:
ID Item Color
1 Car Red
2 Apple Green
3 Trophy Gold
4 Suit Black
I would want the user to fill out a form where they:
Are presented with a dropdown list, to choose items from (based on the existing table).
When they have chosen up to x amount of items, they submit their "inventory" which..
Adds the selected items to their own column in a table that holds "user_inventory"
So this second table (user_inventory) should look something like this:
User_id item_id1 item_id2 item_id3
1 4 3 1
2 3 1 4
3 2 4 1
4 2 4 3
I don't expect you to write the code for me or anything, but I would be thrilled if you could answer these questions:
Is this possible?
Can you direct me to a similar type of thread or article that helps me write the code?
If you can not direct me anywhere, please help me in whichever way you see fit.
It is possible.
Firstly, read from the "existing" db table to create the select menu, example:
<select name="item">
<?php
$sql = "SELECT * FROM existing";
$query = mysqli_query($mysqli, $sql);
while ($result = mysqli_fetch_array($query)) {
$item = $result['item'];
echo "<option value='$item'>$item</option>";
}
?>
</select>
This will create the "Item" select menu, I'm sure you can figure out how to do the other menus by yourself, all that is left now is to submit and store into the new table which I assume you already know how to do.
if(isset($_POST['yoursubmitname'])) {
$item = $_POST['item'];
/// RUN THE INSERT COMMAND HERE //
}
I'm working on a project at home to teach myself PHP PDO. My project is to create a basic version of twitter from scratch. But I'm stuck. What I want to do is to show a list of users (ordered by id) which I can do fine but beside that list of users I want to show whether the currently logged in user is following or not following that person so I can display a link to follow or unfollow them. From what I can see, this really is a question about arrays and foreach loops.
The relevant two tables in the database looks like this (with example data):
users:
id | username
1 | Josh
2 | Sam
3 | Jane
following:
user_id | follower_id
2 | 1
3 | 1
So for example, the currently logged in user Josh (with an id of 1) is following Sam (with an id of 2). A following database row would then say follower_id 1, user_id 2.
I've written two functions to show the id and username of all my users and another to show who the currently logged in person is following. Here they are:
function show_users(){
$sql = "select id, username from users order by id";
$stmt = $GLOBALS['db']->prepare($sql);
$stmt->execute();
$result = $stmt->fetchAll(PDO::FETCH_ASSOC);
return $result;
}
function check_follow($userid){
$sql= "SELECT DISTINCT user_id FROM following WHERE follower_id = '$userid' ";
$stmt = $GLOBALS['db']->prepare($sql);
$stmt->execute();
$result = $stmt->fetchAll(PDO::FETCH_ASSOC);
return $result;
}
This all works fine if I just want to show a list of users ordered by id.
But what I want to do is to show beside the list of users a column that shows whether you are f ollowing that person i.e. and provide a link to 'follow' or 'unfollow' them.
At the moment, the relevant part of my page looks like this:
<?php
$userid = $_SESSION['user']['id'];
$following = check_follow($userid);
$rows = show_users();
?>
<h1>Follow list</h1>
<table>
<tr>
<th>id</th>
<th>Username</th>
<th>Follow status</th>
</tr>
<?php foreach($rows as $row): ?>
<tr>
<td><?php echo $row['id']; ?></td>
<td><?php echo $row['username']; ?></td>
<td><?php
if (in_array($following, $rows)){
echo "<a href='#'>unfollow</a>";
}else{
echo "<a href='#'>follow</a>"; } ?>
</td>
</tr>
<?php endforeach; ?>
</table>
Everything works fine (except for the show who I am/am not follow part), it's not showing 'follow' links for some people and 'unfollow' links for others!
I've spent hours on this. I've read up on arrays, foreach, in_array, PDO fetch statements and tutorials on outputting different data and none of it helps. It doesn't either help that most of the stuff out there is non-pdo.
SOS :)
You don't want to loop over one result set and then makes queries for each row. It is inefficient and the database can do it for you.
Try a join query:
SELECT u.id, u.username, IF(f.follower_id IS NULL, 0, 1) as following
FROM users u
LEFT JOIN following f
ON u.id = f.user_id
AND f.follower_id = $loggedinuser
The LEFT JOIN gives you every row from the users table then any rows in following that match the criteria in the "ON" clause. If there is no match, those columns are set to NULL in the result.
You are now performing two different queries for one result.
You should left join your "following" table something like this
SELECT
`Users`.`userid` as `Users.id`,
`Followers`.`id` as `Followers.id`
FROM
`users` AS `Users"`
LEFT JOIN
`followers` AS `Followers` ON (`Users`.`id` = `Followers`.`userid`)
Then you get the followers of a specific user in the same data set., belonging to a user id, and then you can check if your user id appears in the array, or you could even go further and add a substring within your existing query, but you'll have to read up on that, before you do that you should understand it.