I have multiple columns withing my mysql data base however I need data from 1 of 2 of them. There is either data in column1 or column2 there is no insane where data is available in both.
I have tried the below with no luck. I have also looked around and can't seem to find an easy way of dealing with this.
<?php
$query = "SELECT `column1`,`column2` FROM `table` WHERE `name` LIKE 'Jack'";
$columcheck = $query['column1'];
if ($columcheck == null) {
$columcheck = $query['column2'];
}
echo $columcheck;
?>
I basically just want to echo the column that is not empty.
Thanks in advance.
Lucas.
First off you need to fetch the data as well as actually read it. I put together a little function for you that you can use. You should improve upon it though. Use prepared statements, if you need more than the first result store it in an array and loop through, etc etc.
Also note I set up this function assuming the use of php 7.1+. If that's not the case remove the type hints.
function collectData(\mysqli $connection): ?string {
if ($connection->connect_error) {
return null;
}
$result = $connection->query("SELECT `column1`,`column2` FROM `table` WHERE `name` LIKE 'Jack'");
if ($result->num_rows > 0) {
while($row = $result->fetch_assoc()) {
if($result['column1'])
return $result['column1'];
return $result['column2'];
}
}
}
Related
I have a postgres table with four columns labelled dstart which is date data type,
dend which is also a date data type, dcontract which is a date data type and id which is a integer. I am trying to run a php code to get the data using an array and use it in the body of my application. But when I test the array and try to echo some values... My browser just displays the word array... Is there anyway I can be able to retrieve the data or fix this code? Please see code below
<?php
function getLiveDate($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 $return variable is an array, if you want shows the content, you must use print_r or var_dump not echo.
hello i want to create function with returning data, for example when i have the function advert i want to make it every time show what i need, i have the table id, sub_id, name, date, and i want to create the function that i can print every time what i need advert(id), advert(name), i want to make it to show every time what i need exactly and i want to save all my result in array, and every time grab the exactly row that i want
<?php
function advert($data){
$id = $_GET['id'];
$query = mysql_query("SELECT *FROM advertisement WHERE id = $id");
while($row = mysql_fetch_assoc($query)){
$data = array(
'id' => $row['id']
);
}
return $data;
}
echo advert($data['id']);
?>
but my result every time is empty, can you help me please?
There are so many flaws in this short piece of code that the only good advice would be to get some beginners tutorial. But i'll put some effort into explaining a few things. Hopefully it will help.
First step would be the line function advert($data), you are passing a parameter $data to the method. Now later on you are using the same variable $data in the return field. I guess that you attempted to let the function know what variable you wanted to fill, but that is not needed.
If I understand correctly what you are trying to do, I would pass in the $id parameter. Then you can use this function to get the array based on the ID you supplied and it doesnt always have to come from the querystring (although it could).
function advert($id) {
}
Now we have the basics setup, we want to get the information from the database. Your code would work, but it is also vulnerable for SQL injection. Since thats a topic on its own, I suggest you use google to find information on the subject. For now I'll just say that you need to verify user input. In this case you want an ID, which I assume is numeric, so make sure its numeric. I'll also asume you have an integer ID, so that would make.
function advert($id) {
if (!is_int($id))
return "possible SQL injection.";
}
Then I'll make another assumption, and that is that the ID is unique and that you only expect 1 result to be returned. Because there is only one result, we can use the LIMIT option in the query and dont need the while loop.
Also keep in mind that mysql_ functions are deprecated and should no longer be used. Try to switch to mysqli or PDO. But for now, i'll just use your code.
Adding just the ID to the $data array seems useless, but I guess you understand how to add the other columns from the SQL table.
function advert($id) {
if (!is_int($id))
return "possible SQL injection.";
$query = mysql_query("SELECT * FROM advertisement WHERE id = $id LIMIT 1");
$row = mysql_fetch_assoc($query);
$data = array(
'id' => $row['id']
);
return $data;
}
Not to call this method we can use the GET parameter like so. Please be advised that echoing an array will most likely not give you the desired result. I would store the result in a variable and then continue using it.
$ad = advert($_GET['id']);
if (!is_array($ad)) {
echo $ad; //for sql injection message
} else {
print_r($ad) //to show array content
}
Do you want to show the specific column value in the return result , like if you pass as as Id , you want to return only Id column data.
Loop through all the key of the row array and on matching with the incoming Column name you can get the value and break the loop.
Check this link : php & mysql - loop through columns of a single row and passing values into array
You are already passing ID as function argument. Also put space between * and FROM.
So use it as below.
$query = mysql_query("SELECT * FROM advertisement WHERE id = '".$data."'");
OR
function advert($id)
{
$query = mysql_query("SELECT * FROM advertisement WHERE id = '".$id."'");
$data = array();
while($row = mysql_fetch_assoc($query))
{
$data[] = $row;
}
return $data;
}
Do not use mysql_* as that is deprecated instead use PDO or MYSQLI_*
try this:
<?php
function advert($id){
$data= array();
//$id = $_GET['id'];
$query = mysql_query("SELECT *FROM advertisement WHERE id = $id");
while($row = mysql_fetch_assoc($query)){
array_push($data,$row['id']);
}
return $data;
}
var_dump($data);
//echo advert($data['id']);
?>
I have a select statement where I want to get all rows from a table but seem to be having a mental blockage - this should be elementary stuff but can't seem to get it working.
There are only two rows in the table 'postage_price' - and two columns : price | ref
Select statement is as follows:
$get_postage="SELECT price FROM postage_price ORDER BY ref DESC";
$get_postage_result=mysqli_query($dbc, $get_postage) or die("Could not get postage");
while($post_row=mysqli_fetch_array($dbc, $get_postage_result))
{
$post1[]=$post_row;
}
I am then trying to echo the results out:
echo $post1['0'];
echo $post1['1'];
this is not showing anything. My headache doesn't help either.
while($post_row = mysqli_fetch_array($dbc, $get_postage_result))
{
$post1[] = $post_row['price'];
}
As you see: $post_row in this line: = mysqli_fetch_array($dbc, $get_postage_result) is an array. You are trying to save the whole array value to another array in a block. :)
EDIT
while($post_row = mysqli_fetch_array($get_postage_result))
...
You have $post1[]=$post_row; and $post_row is itself an array. So you can access post data with following: $post1[NUMBER][0] where NUMBER is a $post1 array index and [0] is 0-index of $post_row returned by mysqli_fetch_array.
Probably you wanted to use $post1[]=$post_row[0]; in your code to avoid having array of arrays.
You are passing 1 and 0 as string indexes, this would only work if you had a column called 0 or 1 in you database. You need to pass them as numeric indexes.
Try:
print_r($post1[0]);
print_r($post1[1]);
or
print_r($post['price']);
print_r($post['ref']);
with all your help I have found the error - it is in the mysqli_fetch_array where I had the $dbc which is not required.
$get_postage="SELECT price FROM postage_price ORDER BY ref DESC";
$get_postage_result=mysqli_query($dbc, $get_postage) or die("Could not get postage");
while($post_row=mysqli_fetch_array($get_postage_result))
{
$post1[]=$post_row['price'];
}
instead of:
$get_postage="SELECT price FROM postage_price ORDER BY ref DESC";
$get_postage_result=mysqli_query($dbc, $get_postage) or die("Could not get postage");
while($post_row=mysqli_fetch_array($dbc, $get_postage_result))
{
$post1[]=$post_row['price'];
}
Bad day for me :(
Thanks all
If something does not work in a PHP script, first thing you can do is to gain more knowledge. You have written that
echo $post1['0'];
echo $post1['1'];
Is showing nothing. That could only be the case if those values are NULL, FALSE or an empty string.
So next step would be to either look into $post1 first
var_dump($post1);
by dumping the variable.
The other step is that you enable error display and reporting to the highest level on top of your script so you get into the know where potential issues are:
ini_set('display_errors', 1); error_reporting(~0);
Also you could use PHP 5.4 (the first part works with the old current PHP 5.3 as well, the foreach does not but you could make query() return something that does) and simplify your script a little, like so:
class MyDB extends mysqli
{
private $throwOnError = true; # That is the die() style you do.
public function query($query, $resultmode = MYSQLI_STORE_RESULT) {
$result = parent::query($query, $resultmode);
if (!$result && $this->throwOnError) {
throw new RuntimeException(sprintf('Query "%s" failed: (#%d) %s', $query, $this->errno, $this->error));
}
return $result;
}
}
$connection = new MyDB('localhost', 'testuser', 'test', 'test');
$query = 'SELECT `option` FROM config';
$result = $connection->query($query);
foreach ($result as $row) {
var_dump($row);
}
I write a lot of SELECT * FROM... kind of queries in my web sites. I'd like to write a function that looks after this for me so I can call on it more quickly, without using more advanced techniques like PDO and OOP. Im just confused on how I would call the data I retrieve from the database, particularly when looping through the array's results.
I'd love something like this:
function selectAll($tableName, $limitAmount) {
global $dbConnection;
$query = mysql_query("SELECT * FROM $tableName ORDER BY id LIMIT $limitAmount");
$row_result = mysql_fetch_assoc($query);
return $row_result;
}
Say it was a bunch of news posts. Id like to loop through the results in one of the typical ways:
// CALL THE FUNCTION
selectAll('news_table', '10');
// SOMEHOW LOOP THROUGH RESULTS??
do {
echo "<h2>".$row_result['title']."</h2>";
} while ($row_result = mysql_fetch_assoc($query));
Obviously this isn't how I loop through the bespoke results of a function. Im not even sure if my function is correct.
Any help is greatly appreciated.
EDIT: Forgot to return a result inside the function and call the actual function. My bad. Updated now.
There is no point in having such a function called like yours.
Just make it like this
function fetchAll($query) {
$res = mysql_query($query) or trigger_error("db: ".mysql_error()." in ".$query);
$a = array();
if ($res) {
while($row = mysql_fetch_assoc($res)) $a[]=$row;
}
return $a;
}
and use it with whatever query:
$data = fetchAll("SELECT * FROM news_table ORDER BY id LIMIT 10");
foreach ($data as $row) {
echo $row['title'];
}
An SQL query being a powerful program itself. Do not reduce it's power to silly selects.
Use SQL to represent data processing logic and this helper function to avoid repetitions.
I have 4 columns in my database. Atk,Str,Dex,and Con. Each being INT and then I have a PHP function get_level that takes those 4 columns and determines the correct level for them. I'm trying to select all users in a given range based on these "levels". The get_combat function takes those 4 values and finds the users combat level. This is what I have, which doesn't work.
<?PHP
$query = "SELECT get_level(attack) as atk,
get_level(strength) as str,
get_level(dexterity) as dex,
get_level(constitution) as con,
get_combat(atk,str,dex,con) as level
FROM `users`
WHERE level > 5 AND level < 10";
?>
Is there a way to do this?
What you are trying to do is impossible. MySQL doesn't even know what PHP is or which language is talking to it.
Why not fetch the values and call your function on in in the loop where you iterate over the results?
Depending on how complex the function is you could also create a stored procedure in your database. You cannot write PHP code in that function though.
I think you can't do something like this in SQL. After executing the query you can use the functions. Assuming you are using the old mysql_* functions:
<?php
$result = mysql_query($query);
$newResults = array();
$i = 0;
while( $row = mysql_fetch_assoc($result) ) {
$newResults[$i]['atk'] = get_level($row['attack']);
$newResults[$i]['strength'] = get_level($row['strength']);
/** ect. **/
$newResults[$i]['level'] = get_combat($newResults['atk'],$newResults['str'],$newResults['dex'],$newResults['con']);
}