This is what I have so far. It calls to the database and receives one comment and all of the values that go with it, but I want to get multiple comments with the same id. How do I set up a array to get the multiple comments?
function get_comment_by_id($lake_id) {
global $connection;
$query = "SELECT * ";
$query .= "FROM comments ";
$query .= "WHERE lakeId=" . $lake_id ." ";
//$query .= "LIMIT 1";
$result_set = mysql_query($query, $connection);
confirm_query($result_set);
// REMEMBER:
// if no rows are returned, fetch_array will return false
if ($comment = mysql_fetch_array($result_set)) {
return $comment;
} else {
return NULL;
}
}
you just need to put it in a while loop. instead of
if ($comment = mysql_fetch_array($result_set)) {
return $comment;
} else {
return NULL;
}
do
$rows = array();
while($comment = mysqli_fetch_array($result_set))
$rows[] = $comment;
return $rows;
and you also need to use mysqli_* functions since the mysql_* functions are deprecacted.
In the calling function you should check for an empty array instead of a null value
Related
I want to create a function that automatically makes a connection to the database and performs the given queries but I can't get it to work and it gives no errors.
I think I'm not outputting in the correct way my goal is to output a array that stores all the returned values from the queries.
Here is my code so far hope you can help:
public function db_query() {
$ini = parse_ini_file($_SERVER['DOCUMENT_ROOT'] . '/app.ini');
$mysqli = new mysqli($ini['db_location'], $ini['db_user'], $ini['db_password'], $ini['db_name']);
// create string of queries separated by ;
$query = "SELECT name FROM mailbox;";
$query .= "SELECT port FROM mailbox";
// execute query - $result is false if the first query failed
$result = mysqli_multi_query($mysqli, $query);
if ($result) {
do {
// grab the result of the next query
if (($result = mysqli_store_result($mysqli, 0)) === false && mysqli_error($mysqli) != '') {
echo "Query failed: " . mysqli_error($mysqli);
while ($row = $result->fetch_row()) {
echo $row[0];
}
}
} while (mysqli_more_results($mysqli) && mysqli_next_result($mysqli)); // while there are more results
} else {
echo "First query failed..." . mysqli_error($mysqli);
}
}
Note: I did not add the parameter for the query just for testing
purposes.
public function db_query($mysqli) {
$return = [];
$result = mysqli_query($mysqli, "SELECT name FROM mailbox");
while ($row = $result->fetch_row()) {
$return[] = $row[0];
}
$result = mysqli_query($mysqli, "SELECT port FROM mailbox");
while ($row = $result->fetch_row()) {
$return[] = $row[0];
}
return $return;
}
simple, clean, efficient, always works
I have this function:
//get mgs by orderID
function getOrderMsgs($orderId){
global $conn;
$query = "SELECT * ";
$query .= "FROM msgs ";
$query .= "WHERE orderid=" . $orderId . " ";
$msgset = mysqli_query($conn, $query);
confirm_query($msgset);
while ($msg = mysqli_fetch_assoc($msgset)){
$return[] = $msg;
}
return $return;
}
That returns all messages with a certain message Id. Now what I need to do is check if the returned value is indeed an array since after the query we may find no messages with that specific Id which I believe won't return an array. So far this is what I have:
$msgId = sql_prep($_GET['oid']);
$order = getOrderById($msgId);
$msgs=getOrderMsgs($msgId);
echo '<h2>Order #'.$order['orderid'].': '.$order['title'].'</h2>';
echo '<h3>Message thread</h3>';
foreach($msgs as $msg){
echo $msg['msg'].'<br>'.$msg['sender'].'<br>'.$msg['timestamp'].'<br><br>';
}
And it returns an error if there is no msgs with that id in db.
To see type of a variable you can use gettype
print_r(gettype($_COOKIE));
Make sure you initialize $return before using it. This ensures you are always returning an array.
function getOrderMsgs($orderId){
global $conn;
$return = array(); // initialize variable
$query = "SELECT * ";
$query .= "FROM msgs ";
$query .= "WHERE orderid=" . $orderId . " ";
$msgset = mysqli_query($conn, $query);
confirm_query($msgset);
while ($msg = mysqli_fetch_assoc($msgset)){
$return[] = $msg;
}
return $return;
}
In you code you can then inspect the array and use the number of array elements to decide what to do next.
$order = getOrderById($msgId);
if(count($order) > 0) {
// Found something
} else {
// Nothing found
}
<?php
function get_subject_by_id2() {
global $connection;
$query = "SELECT * ";
$query .= "FROM subjects ";
$query .= "WHERE id= 2 ";
$query .= "LIMIT 1";
$result_set = mysqli_query($connection, $query);
confirm_query($result_set);
// REMEMBER:
// if no rows are returned, fetch_array will return false
if ($subject = mysqli_fetch_array($result_set)) {
return $subject2;
} else {
return NULL;
}
}
echo $subject2['content1'];
echo $subject2['content2'];
?>
I have no idea why this is not working. Please help!
I believe it is not returning NULL, and it returns $subject2. For some reason, it does not work.
Where are you even calling the function? That function isnt being called and hence it cannot return anything
$subject2=get_subject_by_id2(); // forgot to make this call?
echo $subject2['content1'];
echo $subject2['content2'];
Also as suggested by yajakass fix the typo
I am using same query again and again on different pages in between to fetch result. I want to make a function for this query.
$result = mysql_query(" SELECT name FROM tablename where id= '$row[name_id]'");
$row = mysql_fetch_array($result);
echo $row ['name'];
How to make and how to call the function?
sample class stored sample.php
class sample
{
function getName(id)
{
$result = mysql_query("SELECT name FROM tablename where id='$id'");
$row = mysql_fetch_array($result);
return $row ['name'];
}
}
use page include sample.php,then create object,then call getName() function.
<?php
include "db.class.php";
include "sample.php";
$ob=new sample(); //create object for smaple class
$id=12;
$name=$ob->getName($id); //call function..
?>
This is a good idea but first of all you have to create a function to run queries (as you have to run various queries way more often than a particular one)
function dbget() {
/*
easy to use yet SAFE way of handling mysql queries.
usage: dbget($mode, $query, $param1, $param2,...);
$mode - "dimension" of result:
0 - resource
1 - scalar
2 - row
3 - array of rows
every variable in the query have to be substituted with a placeholder
while the avtual variable have to be listed in the function params
in the same order as placeholders have in the query.
use %d placeholder for the integer values and %s for anything else
*/
$args = func_get_args();
if (count($args) < 2) {
trigger_error("dbget: too few arguments");
return false;
}
$mode = array_shift($args);
$query = array_shift($args);
$query = str_replace("%s","'%s'",$query);
foreach ($args as $key => $val) {
$args[$key] = mysql_real_escape_string($val);
}
$query = vsprintf($query, $args);
if (!$query) return false;
$res = mysql_query($query);
if (!$res) {
trigger_error("dbget: ".mysql_error()." in ".$query);
return false;
}
if ($mode === 0) return $res;
if ($mode === 1) {
if ($row = mysql_fetch_row($res)) return $row[0];
else return NULL;
}
$a = array();
if ($mode === 2) {
if ($row = mysql_fetch_assoc($res)) return $row;
}
if ($mode === 3) {
while($row = mysql_fetch_assoc($res)) $a[]=$row;
}
return $a;
}
then you may create this particular function you are asking for
function get_name_by_id($id){
return dbget("SELECT name FROM tablename where id=%d",$id);
}
You should probably parse the database connection as well
$database_connection = mysql_connect('localhost', 'mysql_user', 'mysql_password');
function get_row_by_id($id, $database_link){
$result = mysql_query("SELECT name FROM tablename where id= '{$id}");
return mysql_fetch_array($result);
}
Usage
$row = get_row_by_id(5, $database_connection);
[EDIT]
Also it would probably help to wrap the function in a class.
function getName($id){
$result = mysql_query("SELECT name FROM tablename where id= '$row[name_id]'");
$row = mysql_fetch_array($result);
return $row ['name'];
}
call the function by
$id = 1; //id number
$name = getName($id);
echo $name; //display name
$qVraagGroepenOp = "SELECT * FROM $tabele WHERE $where";
$rVraagGroepenOp = mysql_query ( $qVraagGroepenOp );
$aVraagGroepenOp = mysql_fetch_assoc ( $rVraagGroepenOp )
and I converted that to a function
vraagOp("testtable","testtable_ID = $id");
function vraagOp($table,$where)
{
$qVraagOp = "SELECT * FROM $table WHERE $where";
$rVraagOp = mysql_query( $qVraagOp );
$aVraagOp = mysql_fetch_assoc( $rVraagOp );
return $aVraagOp;
}
only the problem is when i need more then one row i need to use a while loop
$qVraagGroepenOp = "SELECT * FROM testtable where testtype = test";
$rVraagGroepenOp = mysql_query ( $qVraagGroepenOp );
while ( $aVraagGroepenOp = mysql_fetch_assoc ( $rVraagGroepenOp ) )
{
echo "testing <br>";
}
It wont work anymore is there a trick to make my function work with this while loop?
This won't work but I want to reach to something like it
while (vraagOp("testtable","testtype = test"))
{
echo "testing <br>";
}
Is this possible?
This could be done with static variables in the function scope.
function vraagOp($table,$where)
{
static $rVraagOp;
if(!$rVraagOp){
$qVraagOp = "SELECT * FROM $table WHERE $where";
$rVraagOp = mysql_query( $qVraagOp );
}
return mysql_fetch_assoc( $rVraagOp );
}
That should do what you're after.
This function returns an array of rows - it's a generic pattern yu can use almost anywhere you get multiple rows from a query.
function vraagOp($table,$where)
{
$sql= "SELECT * FROM $table WHERE $where";
$query= mysql_query($sql);
if ($query != false)
{
$result = array();
while ( $row = mysql_fetch_assoc($query) )
$result[] = $row;
return $result;
}
return $false;
}
//usage
$rows = vraagOp($table,$where);
if ($rows)
{
foreach ($rows as $row)
use($row);
}
This function will 'cache' the mysql result resource from each unique $table/$where combination, and fetch the next result from it on each subsequent call. It will return an associative array for each row, or false when there are no rows left.
function vraagOp($table, $where)
{
// Holds our mysql resources in a map of "{$table}_{$where}" => resource
static $results = array();
$key = $table . '_' . $where;
if (!isset($results[$key]))
{
// first call of this particular table/where
$results[$key] = mysql_query("SELECT * FROM $table WHERE $where");
}
$row = mysql_fetch_assoc($results[$key]);
if ($row === false)
// remove this key so a subsequent call will start over with a new query
unset($results[$key]);
return $row;
}
// Usage
while ($row = vraagOp("table1", "where field > 7")) {
print_r($row);
}
This
while (vraagOp("testtable","testtype = test"))
{
echo "testing <br>";
}
will work if you change VraagOp() to return false when no matching record was found.
You would have to move the mysql_query() part out of VraagOp(), and just leave the mysql_fetch_assoc part in.
However, I can't really see what benefit there would be? You would just be building a (unnecessary) wrapper around mysql_fetch_assoc(), wouldn't you?
You'll need to turn vraagOp() into an iterator and then use foreach() in order to make this work.
Your example won’t work because the condition is executed on every iteration. That means vraagOp("testtable","testtype = test") would be called with each iteration until it returns a falsely value. mysql_fetch_assoc does that but your function doesn’t.
How can we call function inside while loop example is below :
$sql_gpfsF="SELECT * FROM emp_salary";
$result_gpfsF=mysql_query($sql_gpfsF);
while($row_gpfsF=mysql_fetch_assoc($result_gpfsF))
{
call_function();
}
function call_function()
{
echo " Function Called </ br>";
}