Converting exploded array into string - php

In the project that I am creating, I have a mysql column that is an array of different pieces of data from the database. These pieces of data have info that I want to display. In order to separate these items in the array I used,
$get_query = mysql_query('Select array FROM data');
while($dataRow = mysql_fetch_assoc($getfrnd_query)) {
$array = $dataRow['array'];
if($array != "") {
$data_from_array_column = explode("," $array);
$getdata = mysql_query("SELECT * FROM info WHERE item = $data_from_array_column");
//Then I used a mysql_fetch_assoc to get data based on the item.
}
}
When I run this code, I get an error "Array to string conversion on the line with $getdata".
Is there any way to get this to work?
Thank you.

The problem is that explode returns an array containing the strings in between the character(s) you used as a delimiter (, in your case), not a string.
PHP is getting mad because it doesn't know how to convert your array to a string automatically. So, you will need to convert it yourself. The options are:
You want to select the row where item is equal to the nth element in the array, $data_from_array_column. If this is the case, you need to insert the following line of code after your explode:
$data_from_array_column = $data_from_array_column[0];
If you want to select where it matches any of the elements in the $data_from_array_column array, it will get more complicated. You would need to add this line after the explode:
$data_from_array_column = implode("' OR item='",$data_from_array_column);
and change your query on the next line to:
$getdata = mysql_query("SELECT * FROM info WHERE item='$data_from_array_column'");
This will create a MySQL query that looks some thing like this:
SELECT * FROM info WHERE item='foo' OR item='bar' OR item='bla'

Related

How to add element to php array without it showing as a new array

The intention with the below code is to extract messages from a mysql table, and put each of them inside ONE array with {} around each output. Each output consists of various parameters as you can see, and is an array in itself.
What the code does is that each time the loop is processed, in the JSON array that this later is converted into, it wraps the output in []´s, hence it´s now a new array which is created.
What I get is:
[{"sender":"ll","message":"blah","timestamp":"2016-12-21 14:43:04","username":"","msgtype":"","threadid":"32629016712222016034323"},{"sender":"kk","message":"blahblah","timestamp":"2016-12-21 14:43:23","username":"","msgtype":"","threadid":"32629016712222016034323"},{"sender":"ll","message":"blahblahblah","timestamp":"2016-12-21 14:43:47","username":"","msgtype":"","threadid":"32629016712222016034323"}],[{"sender":"ll","message":"blahblahblahblah","timestamp":"2016-12-21 14:43:04","username":"","msgtype":"","threadid":"92337321312222016034304"},{"sender":"kk","message":"blahblahblahblahblah","timestamp":"2016-12-21 14:44:05","username":"","msgtype":"","threadid":"92337321312222016034304"}]]
And what I want is:
[{"sender":"ll","message":"blah","timestamp":"2016-12-21 14:43:04","username":"","msgtype":"","threadid":"32629016712222016034323"},{"sender":"kk","message":"blahblah","timestamp":"2016-12-21 14:43:23","username":"","msgtype":"","threadid":"32629016712222016034323"},{"sender":"ll","message":"blahblahblah","timestamp":"2016-12-21 14:43:47","username":"","msgtype":"","threadid":"32629016712222016034323"}],{"sender":"ll","message":"blahblahblahblah","timestamp":"2016-12-21 14:43:04","username":"","msgtype":"","threadid":"92337321312222016034304"},{"sender":"kk","message":"blahblahblahblahblah","timestamp":"2016-12-21 14:44:05","username":"","msgtype":"","threadid":"92337321312222016034304"}]
How do I proceed to get the right result here?
$data = array ();
foreach($threads as $threadid){
$sql = ("SELECT sender,message,timestamp,username,msgtype,threadid FROM Messages WHERE threadid = '$threadid' AND subject = '' AND timestamp > '$newtimestamp' ORDER BY timestamp");
$arrayOfObjects = $conn->query($sql)->fetchAll(PDO::FETCH_OBJ);
$data[] = $$arrayOfObjects;
}
And FYI, $threadid is another array containing... threadids, and the loop correctly fetches these one by one, that´s not where the problem is.
Thanks in advance!!
You are doing O(N) database queries, consider doing just O(1) using an IN expression in your where clause. No need for a foreach loop and you'll get all your data in one array.
SELECT ... FROM Messages WHERE threadid IN (1, 2, 3, ...) AND ...
You might have to use a prepared statement for that.
I think you are searching for PDO::FETCH_OBJ.
You had FETCH_ASSOC, which will return an array of associative arrays.
FETCH_OBJwill return an array ob stdObjects.
Also you reassigned $array to itself when doing $array[] = $array;..
$data = array();
foreach($threads as $threadid){
$sql = ("SELECT sender,message,timestamp,username,msgtype,threadid FROM Messages WHERE threadid = '$threadid' AND subject = '' AND timestamp > '$newtimestamp' ORDER BY timestamp");
// here it is:
$arrayOfObjects = $conn->query($sql)->fetchAll(PDO::FETCH_OBJ);
$data[] = $arrayOfObjects;
}
// now you can encode that as json and show it:
echo json_encode($data);
#akuhn
Well, I decided to give your suggestion one more try, and managed to do it in a none prepared way. I´m aware that this is supposed to be risky, but so far this project just needs to work, then have the php codes updated to safer versions, and then go live. It works, so thanks a bunch!
$sql = ("SELECT sender,message,timestamp,username,msgtype,threadid FROM Messages WHERE threadid IN ('" . implode("','",$threadid) . "') AND subject = '' AND timestamp > '$newtimestamp' ORDER BY timestamp");
$data = $conn->query($sql)->fetchAll(PDO::FETCH_OBJ);

PHP function issues with array

I have a postgres table with four columns labelled dstart which is date data type,
dend which is also a date data type, dcontract which is a date data type and id which is a integer. I am trying to run a php code to get the data using an array and use it in the body of my application. But when I test the array and try to echo some values... My browser just displays the word array... Is there anyway I can be able to retrieve the data or fix this code? Please see code below
<?php
function getLiveDate($campid)
{
global $conn,$agencies;
$return=array(
'livedate'=>'',
'campid'=>'',
'enddate'=>'',
'dateContract'=>'',
);
$sql = "SELECT id, dcontract, dstart, dend
FROM campaigns
WHERE id = '".$campid."' ORDER BY dstart DESC LIMIT 1";
$r = pg_query($conn,$sql);
if ($r)
{
$d = pg_fetch_array($r);
if (!empty($d))
{
$return['livedate'] = $d['dstart'];
$return['campid'] = $d['id'];
$return['enddate'] = $d['dend'];
$return['dateContract'] = $d['dcontract'];
}
}
#pg_free_result($r);
return $return;
}
I am pretty sure, your array $d is "multi-dimensional" and pg_fetch_array() returns an array of arrays, because the result of SQL queries in general may contain multiple rows. You limited it to one row, but you certainly get the correct values by assinging $return['livedata'] = $d[0]['dstart']; or $return['livedata'] = $d['dstart'][0]; and so on (I am not familiar with that particularly function for I usually use MySQL instead of Postgre).
Besides, try echoing your data by means of print_r() instead of echo.
The $return variable is an array, if you want shows the content, you must use print_r or var_dump not echo.

Remove a loop to find existing numbers in database to one single query

I am sending an array of numbers separated by commans to server. Basically on server database I have a field that cotains numbers.Server side code checks which numbers are in database and send me the array of those numbers.
Following code is what I am using...
public function already_user()
{
$contacts=$this->input->post('contact');
//$contacts is an array.
$user= explode(',',$contacts);
foreach($user as $number)
{
$data = array (
'username' =>$number
);
$usernumber = $this->chat_model->get(array('username'=>$number)); // a simple query to datbase that check if number exists in database column or not.
if(!$usernumber==""){
$value[]=$usernumber;
}
}
echo json_encode($value);
}
Only drawback about this code is , its extremely slow.... If i have 1000+ numbers it takes a minute.since its a loop Is there any way to fasten this up. Any single mysql query??
Why don't you just write a single query? Parse the string to get an array and query the table in a single go.
$contact_array = array_map('trim', explode(', ', $contacts));
$all_usernumbers = $this->chat_model->get(array('username IN'=> $contact_array));
which should (depending of what your chat_model->get() accepts), translate to:
SELECT * FROM your_table WHERE username IN ('123', '345')
This is all pseudocode since I don't know what your framework accepts but the SQL query above should be valid.

php count returning 1 not 0 from mysql_query when empty

I am trying to get a count and I am getting 1 instead of 0 from it. I have looked thoroughly though the web and this site. I have even been trying to figure it out on my own for a long time. I keep coming empty handed here.
So Basically what I am trying to do is make a like system for my users. I can get everything to work correctly the count works except for one thing. When they have liked it it returns 1 not 0 which it should be.
Here is my code for the count. I am not posting all the coding for security reasons and it really doesn't need to since its about the counting part not the rest.
$sql_like = mysql_query("SELECT * FROM posts WHERE mem2_id='$id' ORDER BY post_date DESC LIMIT 40");
while($row = mysql_fetch_array($sql_like)){
$like1 = $row['like_array'];
$like3 = explode(",", $like1);
$likeCount = count($like3);
}
So here is the code that determines the number. Any ideas what is wrong with this? Why its returning 1 not 0 when the item is empty?
// you do escape your id right??? (sql injection prevention)
$sql_like = mysql_query("SELECT * FROM posts WHERE mem2_id='$id' ORDER BY post_date DESC LIMIT 40");
while($row = mysql_fetch_array($sql_like)){
$likeCount = 0;
$like1 = trim($row['like_array']);
if ($like1) {
$like3 = explode(",", $like1); // exploding emtpy string would result in array('')
$likeCount = count($like3);
}
}
Calling explode on an empty string gives an array containing the empty string. This is one element, not zero.
I would suggest that you change your database design if possible so that you don't store the values separated by commas. Use a separate table instead.
If you can't change the database design you can handle the empty string separately.
count() returns the number of indexes in an array or something in an object (PHP: count - Manual).
if a string var is used rather than an array or object it returns 1. it has to get a null value in order to return 0.
you can give it a go by trying:
print count("");
and
print count(null);
You'll have better luck if you use explode() to break the sql output into an array and then run a check with an if statement. Something like the following:
$like3 = explode(',',$like1);
if (count($like1)=1 && $like1[0] == '')
// etc ..
I hope this helps

cast text field to array in mysql select query

I have a table in MySQL database. In that table there is a text field called 'selection' that hold numbered values, separated by a pipe char (example: 44|5|23|546|.....). I also have a php array: $values = array(63,35,7,5);
I need to refer to the 'selection' field as array of options (separated by '|') and select only the rows that contain at least one of the number in $values array.
I hope i explained my problem accurately enough, because my English is very poor... Thanks.
If you want to get row that contains at least one number in $values array, the SQL looks like this:
$values = array(63,35,7,5);
foreach ($values as $value) {
$sql = "select * from tablename where selection like '%{$value}|%' or '%|{$value}%'";
}
If the values in the array are in the appropriate order for search already, you can build your query with something like this:
$selection_searched = implode('|', $values);
$query = "SELECT * FROM your_table WHERE selection = '$selection_searched'";
Beware that you would probably want to validate the array $values fisrt, to check if it isn't empty, etc. Check out the manual for: http://php.net/implode

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