I have created a simple function which takes user id and show total no. of post by the user id
function totalpost($user_id){
$sql = 'SELECT * FROM posts WHERE u_id='.$user_id;
$total = mysql_num_rows(mysql_query($sql)) or die(mysql_errno());
return $total;
}
Its working fine, but when 0 record found, it not returns anything.
I want to return 0 if there are no record found
Please help
function totalpost($user_id){
$sql = 'SELECT count(*) FROM posts WHERE u_id='.intval($user_id);
$res = mysql_query($sql)) or trigger_error(mysql_error().$sql);
$row = mysql_fetch_row($res);
return $row[0];
}
not because you need 0, but because you have to always use count() instead of selectiong all users posts which can be big load of data.
Try this query:
SELECT COUNT(*) FROM posts WHERE u_id=xx
By using the COUNT function you will guarantee a 0 will be returned even if no rows match the WHERE clause.
Related
I'm new to php and I've searched for the past hour and read all the documentation I could find and nothing is helping. I have a table that has a bunch of rows of data. I'm trying to pick one column from the whole table and add them all together. Here is what I got. All this tells me is how many rows there are that match my query, not the total sum of column I want. Any help is appreciated.
$res1 = $db->prepare('SELECT sum(distance) FROM trip_logs WHERE user_id = '. $user_id .' AND status = "2"');
$res1->execute();
$sum_miles = 0;
while($row1 = $res1->fetch(PDO::FETCH_ASSOC)) {
$sum_miles += $row1['distance'];
}
echo $sum_miles;
You're only returning one row in this instance. Modify your summed column to have an alias:
SELECT SUM(distance) AS totDistance FROM trip_logs ....
Now you can can fetch the row -
$row = $res1->fetch(PDO::FETCH_ASSOC);
echo $row['totDistance'];
No need to loop.
You can use SUM() without explicitely grouping your rows because if you use a group function in a statement containing no GROUP BY clause, it is equivalent to grouping on all rows.
If however you want to use the SUM() function for something slightly more complicated you have to group your rows so that the sum can operate on what you want.
If you want to get multiple sums in a single statement, for example to get the distance for all users at once, you need to group the rows explicitely:
$res1 = $db->prepare("
SELECT
SUM(distance) AS distance,
user_id
FROM trip_logs WHERE status = '2'
GROUP BY user_id
");
$res1->execute();
while ($row = $res1->fetch(PDO::FETCH_ASSOC))
{
echo "user $row[user_id] has runned $row[distance] km.\n";
}
This will return the sum of distances by user, not for all users at once.
Try this if you are using a Class :
class Sample_class{
private $db;
public function __construct($database) {
$this->db = $database;
}
public function GetDistant($user_id,$status) {
$query = $this->db->prepare("SELECT sum(distance) FROM trip_logs WHERE user_id =? AND status =?");
$query->bindValue(1, $user_id);
$query->bindValue(2, $status);
try{ $query->execute();
$rows = $query->fetch();
return $rows[0];
} catch (PDOException $e){die($e->getMessage());}
}
}
$dist = new Sample_class($db);
$user_id = 10;
$status = 2;
echo $dist->GetDistant($user_id,$status);
I'm trying to get the profiles names which are assigned to a specific subcategory
with id=9. When I run the code below, I get the profiles that I want but for some
reason the ORDER BY clause in the foreach loop doesn't sort them by their name
alphabetically. Instead they are ordered in the same way they are ordered inside the
'profiles' field in 'subcategories' table (the IDs for the profiles are comma separated).
For example if in subcategories['profiles'] I have ',5,1,2' the profiles names will be displayed
in the following order:
Profile with ID=5
Profile with ID=1
Profile with ID=2
I'm using the explode() function to get the ID for each profile inside the 'subcategory'
table and then use that ID to retrieve their information from the 'profile' table using
a query inside the foreach loop.
Am I missing anything here? Thanks for your help.
Here's my code:
<?php
$subcategories=mysql_query("select * from subcategories where id='9'");
while ($subcategories = mysql_fetch_array($subcategories))
{
$profiles = $subcategories['profiles'];
$profiles = explode(',', $profiles);
foreach ($profiles as $p)
{
$all_places = mysql_query("select * from profile where id='$p' and active='1' order by name asc");
while ($profile = mysql_fetch_array($all_places))
{
echo $profile['name'];
}
}
}
?>
Well the reason why your results do not order by name is because you are retrieving every profile with a new SQL query in your foreach loop for $profiles. So effectively in your scenario, you will end up with 3 SQL queries that returns 1 profile each. Hence, when the "order by" clause is declared, it orders by name within each query, which only contains 1 result each.
does using an IN statement work for you? Eg.
<?php
$subcategories=mysql_query("select * from subcategories where id='9'");
while ($subcategories = mysql_fetch_array($subcategories))
{
//i assume $subcategories['profiles'] are integers separated by comma as mentioned
$profiles = $subcategories['profiles'];
$all_places = mysql_query("select * from profile where id IN ($profiles) and active='1' order by name asc");
while ($profile = mysql_fetch_array($all_places))
{
echo $profile['name'];
}
}
?>
I have this query in model:
public function Games() {
$q = $this->db->select('games.id, games.title, games.slug, games.dev_id, games.dev, games.plat_id, games.plat');
$q = $this->db->from('games');
$q = $this->db->join('rates', 'games.id = rates.game_id');
$q = $this->db->select_avg('rates.rate');
$q = $this->db->get();
return $q->result();
}
My goal is listing everything from games, additionally getting average rate from rates when available. Now it only shows those rows which are in both tables. How can I solve this?
Use this instruction
$this->db->select('games.id, games.title, games.slug, games.dev_id, games.dev, games.plat_id, games.plat');
$this->db->select_avg('rates.rate');
$this->db->from('games');
$this->db->join('rates', 'games.id = rates.game_id','left');
$this->db->group_by('rates.game_id');
$q = $this->db->get();
Left join will bring multiple results. using avg and group by will restrict to fetch only one row against each record.
i need to take only the items from the table "__sobi2_item" that are in the same country of the user.And use this results for the rest of the function Showupdatelisting. This is my php script:
<?php
function showUpdatedListing()
{
//i found the user country field value...
global $database;
$user =& JFactory::getUser();
$userId = $user->get( 'id' );
$sql = "SELECT (id) FROM #__community_fields WHERE fieldcode= 'FIELD_COUNTRY'";
$database->setQuery( $sql );
$fieldID = $database->loadResult();
$sql = "SELECT (value) FROM #__community_fields_values WHERE field_id= {$fieldID} && user_id= {$userId}";
$database->setQuery( $sql );
$usercountry = $database->loadResult();
// From all the entries i take only ones that have country field like the user has...
$query = "SELECT `data_txt`, `itemid`, `fieldid` FROM `#__sobi2_fields_data` WHERE (`fieldid` = 6) AND ('data_txt' = {$usercountry})";
$database->setQuery($query);
$ResultsArray = $database->loadObjectList();
// We need something here like a Query to load only the entries from $ResultsArray... ??
//....instead of this...
$config =& sobi2Config::getInstance();
$database = $config->getDb();
$now = $config->getTimeAndDate();
$query = "SELECT itemid FROM #__sobi2_item WHERE (published = 1 AND publish_down > '{$now}' OR publish_down = '{$config->nullDate}') ORDER BY last_update DESC LIMIT 0, 30";
$database->setQuery($query);
$sids = $database->loadResultArray();
// ......... show update function goes on...
?>
can anyone help me to connect and adjust these query? thanks.
NB:with the last query (4) i need to filter items of the $ResultsArray taking only ones published and ordering them by last_update. i know it is wrong and now there is no connection with the query before. This is how i have tables in mysql:
_sobi2_fields_data:
itemid
fieldid
data_txt --->(is a description column for each field)
_sobi2_item:
itemid
published --->( 1 if true, 0 if false )
last_update --->(date of the last update for the item, also equal to the publication date if there are no changes)
thanks.
I don't know what you are trying to ask as well. Your last query (number 4) doesn't make sense to me, how is it linked to the above queries?
[EDIT] I've linked your 4th table above assuming itemid is the primary key for the items in sobi2_item table and that the value is linked to the sobi_fields_data table via itemid.
SELECT
cf.id,
sfd.data_txt,
sfd.itemid,
sfd.fieldid
FROM #__community_fields cf
INNER JOIN #__community_fields_values cfv ON cf.id=cfv.field_id
INNER JOIN #__sobi2_fields_data sfd ON cfv.value=sfd.data_txt
INNER JOIN #__sobi2_item si ON sfd.itemid=si.itemid
WHERE cf.fieldcode='FIELD_COUNTRY'
AND cfv.user_id=$userId
AND sfd.fieldid=6
AND si.published=1
AND (si.publish_down > '{$now}' OR si.publish_down = '{$config->nullDate}')
ORDER BY si.last_update DESC LIMIT 0, 30
Good luck!
I want to find out how many rows are in a table. The database that I am using is a MySQL database. I already have a Db_Table class that I am using for calls like fetchAll(). But I don't need any information from the table, just the row count. How can I get a count of all the rows in the table without calling fetchAll()?
$count = $db->fetchOne( 'SELECT COUNT(*) AS count FROM yourTable' );
Counting rows with fetchAll considered harmful.
Here's how to do it the Zend_Db_Select way:
$habits_table = new Habits(); /* #var $habits_table Zend_Db_Table_Abstract */
$select = $habits_table->select();
$select->from($habits_table->info(Habits::NAME), 'count(*) as COUNT');
$result = $habits_table->fetchRow($select);
print_r($result['COUNT']);die;
Proper Zend-Way is to use Zend_Db_Select like this:
$sql = $table->select()->columns(array('name', 'email', 'status'))->where('status = 1')->order('name');
$data = $table->fetchAll($sql);
$sql->reset('columns')->columns(new Zend_Db_Expr('COUNT(*)'));
$count = $table->getAdapter()->fetchOne($sql);
This is how it's done in Zend_Paginator. Other option is to add SQL_CALC_FOUND_ROWS before your column list and then get the number of found rows with this query:
$count = $this->getAdapter()->fetchOne('SELECT FOUND_ROWS()');
You could do a
SELECT COUNT(*)
FROM your_table
$dbo->setFetchMode( Zend_Db::FETCH_OBJ );
$sql = 'SELECT COUNT(*) AS count FROM #table';
$res = $dbo->fetchAll( $sql );
// $res[0]->count contains the number of rows
I'm kind of a minimalist:
public function count()
{
$rows = $db->select()->from($db, 'count(*) as amt')->query()->fetchAll();
return($rows[0]['amt']);
}
Can be used generically on all tables.
Add count capability to your Zend_DB Object To count all table rows
public function count()
{
return (int) $this->_table->getAdapter()->fetchOne(
$this->_table->select()->from($this->_table, 'COUNT(id)')
);
}