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']);
}
Related
hi guy's i have a question.
how to declare a multiple where clause condition inside one php only.
i have try to make my project has a minimum of a php file. i want to make my where clause inside one php file only.
this is the problem i mean. i want to put my code into one php file or inside one <?php ?>. the php code like this
<?php
include("../../Connections/koneksi.php");
$date1= $_POST['date1'];
// Data for Titik1
$sql = "SELECT * FROM termocouple where tanggal='$date1' AND silo='Silo 1'";
$query = mysqli_query($db,$sql);
$rows = array();
while($tmp= mysqli_fetch_assoc($query)) {
$rows[] = $tmp;
}
echo json_encode($rows);
mysqli_close($db);
?>
on the code above the query has select table termocouple and the filter of where condition is tanggal and silo. now the problem is i have 12 php file like that. and the different of every php is from the selecting silo, i put Silo 1,Silo 2,Silo 3, ....Silo 12.
please someone help me with this. i want to make it simple in one php file. im really appreciated when you give me an example
In order to minimize your code, if you are using the same query or code more than one time in the same project, it is more recommended to create a function, that you will call anytime you need to execute the code.
So here, since you are using the same query 12 times, you will have to create a function that executes this query, and then call this function every time you want to execute the query.
The function takes parameters, so you will have to give the function the database connection parameter $db in order to connect to the database since you are using this connection inside the function, and then you have to add the values of the where clause to the parameters also.
So your function here will take the database connection $db, $date1 fetched from $_POST, and $silo fetched from $_POST
At the end of the function, you can return any value you wish to return, so in your case, you will have to return the $rows array fetched from the query
Create a common php fileand create a function in it.
Lets say the file name is libraries.php
in this file write the following code:
<?php
function getRows($db, $date, $silo) {
$sql = "SELECT * FROM termocouple where tanggal='$date' AND silo='$silo'";
$query = mysqli_query($db, $sql);
$rows = array();
while($tmp= mysqli_fetch_assoc($query)) {
$rows[] = $tmp;
}
return json_encode($rows);
}
?>
And in each of the files where you are calling the query you will remove the php code and replace it with the following:
<?php
include("../../Connections/koneksi.php");
include("{path-to-file}/libraries.php");
$date1= $_POST['date1'];
$silo = $_POST['silo'];
$rows = getRows($db, $date1, $silo) ;
?>
I am assuming these 12 PHPs are called in diff scenarios. Why dont you pass some param from client side so that the PHP knows which scenario to execute.
$date1= $_POST['date1'];
$silo= $_POST['silo'];//This could be 'Silo 1 OR 'Silo 2' etc.
// Data for Titik1
$sql = "SELECT * FROM termocouple where tanggal='$date1' AND silo='$silo'";
$query = mysqli_query($db,$sql);
I have a mysql query:
$analyse_ot1="SELECT COUNT(*) AS ot_count FROM first, base, users
WHERE base.base_id=$base
AND
users.base_id=$base
AND
users.id=first.user_id
AND
first.$sub='OT'";
$result_ot1=mysqli_query($con,$analyse_ot1);
$row_ot1= mysqli_fetch_assoc($result_ot1);
$total_ot1= $row_ot1['ot_count'];
$otper1=($total_ot1/$total)*100;
I will be re-using this code many times on a web-page and want to be able to run it as part of a loop.
I don't want to have to rename my variables each time (where $result_ot1 become $result_ot2 etc...)
I've tried introducing an indexing variable $x and then appending it to another variable name:
$x=2;
$result_ot.$x=....
But , it doesn't want to work.
Any suggestions? I have an idea that arrays might be needed but I'm concerned that the queries will be throwing up arrays and I'm not sure an array in an array isn't going to set my computer on fire...
A hint to use your query everywhere.
//declare this in a folder, 'functions.php', for example
function analyse($base, $sub, $con)
{
$analyse_ot1 = 'SELECT COUNT(*) AS ot_count FROM first, base, users'
." WHERE base.base_id=$base AND users.base_id=$base"
." AND users.id=first.user_id AND first.$sub='OT'";
$result_ot1 = mysqli_query($con, $analyse_ot1);
$row_ot1 = mysqli_fetch_assoc($result_ot1);
return $row_ot1['ot_count'];
}
And in any other place of your project:
include 'functions.php';
$total_ot1 = analyse($base, $sub, $con);
$otper1 = ($total_ot1 / $total) * 100;
I did not understand well the loop thing. But in order to dave your results in an array, you could just do this:
$totalCounts = [];
foreach(loop){
$total_current = analyse($base, $sub, $con);
$totalCounts[] = $total_current;
}
And you will have $totalCounts that will be an array of the query result that we find in our function. That could be a way of saving your results in an array.
You could do it associative also:
$x = 0;
foreach(loop){
$total_current = analyse($base, $sub, $con);
$totalCounts['count_'.$x] = $total_current;
$x++;
}
So, if you now access: $totalCounts['count_3'] you would be accessing the result of the query on the third loop, for example.
I don't know if this is your answer. But maybe it helped a bit.
I have a postgres table with four columns labelled dstart which is date data type,
dend which is also a date data type, dcontract which is a date data type and id which is a integer. I am trying to run a php code to get the data using an array and use it in the body of my application. But when I test the array and try to echo some values... My browser just displays the word array... Is there anyway I can be able to retrieve the data or fix this code? Please see code below
<?php
function getLiveDate($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.
This question already has answers here:
Closed 10 years ago.
Possible Duplicate:
Is it possible to query a tree structure table in MySQL in a single query, to any depth?
I have an admin area I created that pulls data from the mysql database using php and display the results in a table. Basically it shows a parent category, then the first sub category below it, then the third level sub category/subject.
It works perfectly but as I am new to mysql and php I am sure that it the code needs to be improved in order to save db resources as while building the table I use 3 while loops and in each loop make a mysql query which I am sure is the wrong way to do it.
Can somebody offer me some assistance for the best way of doing this?
Here is the code:
$query = mysql_query("SELECT * FROM categories WHERE
parent_id is null
order by cat_id asc;", $hd)
or die ("Unable to run query");
while ($row = mysql_fetch_assoc($query)) {
echo '<tr style="font-weight:bold;color:green;"><td>'. $row ['cat_id'].'</td><td>'.$row['cat_name'].'</td><td>'.$row ['parent_id'].'</td><td>'.$row['active'].'</td><td>'.$row ['url'].'</td><td>'.$row['date_updated'].'</td></tr>' ;
$query2 = mysql_query("SELECT * FROM categories WHERE
(active = 'true' AND parent_id = ".$row ['cat_id'].")
order by cat_id asc;", $hd)
or die ("Unable to run query");
while ($row2 = mysql_fetch_assoc($query2)) {
echo '<tr style="font-weight:bold;"><td>'. $row2['cat_id'].'</td><td>'.$row2 ['cat_name'].'</td><td>'.$row2['parent_id'].'</td><td>'.$row2 ['active'].'</td><td>'.$row2['url'].'</td><td>'.$row2 ['date_updated'].'</td></tr>' ;
$query3 = mysql_query("SELECT * FROM categories WHERE
(active = 'true' AND parent_id = ".$row2 ['cat_id'].")
order by cat_id asc;", $hd)
or die ("Unable to run query");
while ($row3 = mysql_fetch_assoc($query3)) {
echo '<tr><td>'. $row3['cat_id'].'</td><td>'.$row3['cat_name'].'</td><td>'.$row3 ['parent_id'].'</td><td>'.$row3['active'].'</td><td>'.$row3 ['url'].'</td><td>'.$row3['date_updated'].'</td></tr>' ;
}
}
}
EDIT
Ok so I did a bit of research and this is where I am:
Probably for a small database my approach is fine.
For a bigger database using an array to store the data would probably mean I need to use a recursive approach which might use up too much memory. Would love to hear what people think, would it still be better than looping db queries in the nested while loops?
I found the following thread where there is an answer to do this without reccursion and with only one query. Not sure if I need to add a position column to my current design:
How to build unlimited level of menu through PHP and mysql
If I rebuild the design using the nested sets model instead of adjacency model then the mysql query would return the results in the required order however maintaining the nested sets design is above my head and I think would be overkill.
That's it. If anyone has any input on top of that please add to the conversation. There must be a winning approach as this kind of requirement must be needed for loads of web applications.
I would think you could do something like this:
SELECT * FROM categories
WHERE active = 'true'
ORDER BY parent_id, cat_id
This would give you all your categories ordered by parent_id, then by cat_id. You would then take the result set and build a multi-dimensional array from it. You could then loop through this array much as you currently do in order to output the categories.
While this is better from a DB access standpoint, it would also consume more memory as you need to keep this larger array in memory. So it really is a trade-off that you need to consider.
There is a lot to fix there, but I'll just address your question about reducing queries. I suggest getting rid of the WHERE clauses all together and use if statements within the while loop. Use external variables to hold all the results that match a particular condition, then echo them all at once after the loop. Something like this (I put a bunch of your stuff in variables for brevity)
//before loop
$firstInfoSet = '';
$secondInfoSet = '';
$thirdInfoSet = '';
//in while loop
if($parentID == NULL)
{
$firstInfoSet.= $yourFirstLineOfHtml;
}
if($active && $parentID == $catID) // good for query 2 and 3 as they are identical
{
$secondInfoSet.= $yourSecondLineOfHtml;
$thirdInfoSet.= $yourThirdLineOfHtml;
}
//after loop
echo $firstInfoSet . $secondInfoSet . $thirdInfoSet;
You can now make whatever kinds of groupings you want, easily modify them if need be, and put the results wherever you want.
--EDIT--
After better understanding the question...
$query = mysql_query("SELECT * FROM categories order by cat_id asc;", $hd);
$while ($row = mysql_fetch_assoc($query)){
if($row['parent_id'] == NULL){
//echo out your desired html from your first query
}
if($row['active'] && $row['parent_id']== $row['cat_id']){
//echo out your desired html from your 2nd and 3rd queries
}
}
I'm using PHP ADOdb and I can get the result set:
$result = &$db->Execute($query);
How do I get the field names from that one row and loop through it?
(I'm using access database if that matters.)
It will depend on your fetch mode - if you setFetchMode to ADODB_FETCH_NUM (probably the default) each row contains a flat array of columns. If you setFetchMode to ADODB_FETCH_ASSOC you get an associative array where you can access each value by a key. The following is taken from ADODB documentation - http://phplens.com/lens/adodb/docs-adodb.htm#ex1
$db->SetFetchMode(ADODB_FETCH_NUM);
$rs1 = $db->Execute('select * from table');
$db->SetFetchMode(ADODB_FETCH_ASSOC);
$rs2 = $db->Execute('select * from table');
print_r($rs1->fields); # shows array([0]=>'v0',[1] =>'v1')
print_r($rs2->fields); # shows array(['col1']=>'v0',['col2'] =>'v1')
To loop through a set of results:
$result = &$db->Execute($query);
foreach ($result as $row) {
print_r($row);
}
Small improvement to the solution posted by #thetaiko.
If you are ONLY needing the field names, append LIMIT 1 to the end of your select statement (as shown below). This will tell the server to send you a single row with column names, rather than sending you the entire table.
SELECT * FROM table LIMIT 1;
I'm working with a table that contains 9.1M records, so this minor change speeds up the query significantly!
This is a function I use to return a field array - I've stripped out some extra stuff that, for example, allows it to work with other DBs than MySQL.
function getFieldNames($strTable, $cn) {
$aRet = array();
# Get Field Names:
$lngCountFields = 0;
$strSQL = "SELECT * FROM $strTable LIMIT 1;";
$rs = $cn->Execute($strSQL)
or die("Error in query: \n$strSQL\n" . $cn->ErrorMsg());
if (!$rs->EOF) {
for ($i = 0; $i < $rs->FieldCount(); $i++) {
$fld = $rs->FetchField($i);
$aRet[$lngCountFields] = $fld->name;
$lngCountFields++;
}
}
$rs->Close();
$rs = null;
return $aRet;
}
Edit: just to point out that, as I say, I've stripped out some extra stuff, and the EOF check is therefore no longer necessary in the above, reduced version.
I initally tried to use MetaColumnNames, but it gave differing results in VisualPHPUnit and actual site, while running from the same server, so eventually
I ended up doing something like this:
$sql = "select column_name, column_key, column_default, data_type, table_name, table_schema from information_schema.columns";
$sql .= ' where table_name="'.$table.'" and table_schema="'.$database_name.'"';
$result = $conn->Execute($sql);
while($row = $result->fetchRow()) {
$out[] = strToUpper($row['column_name']);
}
I think it should work with mysql, mssql and postgres.
The benefit of doing it like this, is that you can get the column names, even if a query from a table returns an empty set.
If you need the Coloumn names even for empty tables or for joins about multiple tables use this:
$db->Execute("SELECT .......");
// FieldTypesArray - Reads ColoumnInfo from Result, even for Joins
$colInfo = $res->FieldTypesArray();
$colNames = array();
foreach($colInfo as $info) $colNames[] = $info->name;
The OP is asking for a list of fieldnames that would result of executing an sql statement stored in $query.
Using $result->fetchRow(), even with fetch mode set to associative, will return nothing if no records match the criteria set by $query. The $result->fields array would also be empty and would give no information for getting the fieldnames list.
Actually, we don't know what's inside the $query statement. Besides, setting limit to 1 may not compatible with all database drivers supported by PHP ADOdb.
Answer by Radon8472 is the right one, but the correct code could be:
$result = $db->Execute($query);
// FieldTypesArray - an array of ADOFieldObject Objects
// read from $result, even for empty sets or when
// using * as field list.
$colInfo = [];
if (is_subclass_of($result, 'ADORecordSet')){
foreach ($result->FieldTypesArray() as $info) {
$colInfo[] = $info->name;
}
}
I have the habit of checking the class name of $result, for as PHP ADOdb will return false if execution fails.