I have function in CodeIgniter to retrieve latest posts from 2 tables:
public function get_latest_comments($amount)
{
$query = $this->db->query('
SELECT *, FROM_UNIXTIME(date) AS timestamp
FROM comments
ORDER BY timestamp DESC
LIMIT 5
');
if ($query->num_rows() > 0) {
$result = $query->result_array();
for ($i = 0; $i < sizeof( $result ); $i++) {
$result[$i]['author_info'] = $this->comments_model->get_comment_author( $result[$i]['id'] );
$result[$i]['date'] = mdate( "%M %m, %Y", $result[$i]['date'] );
if ($result[$i]['section'] === 'blog') $loc = 'blog_posts';
if ($result[$i]['section'] === 'core') $loc = 'public_posts';
$this->db->select( 'title, slug' );
$query = $this->db->get_where( $loc, array('id' => $result[$i]['location']) );
$result[$i]['post_title'] = $query->row( 'title' );
$result[$i]['url'] = base_url() . $result[$i]['section'] . '/view/' . $query->row( 'slug' ) . '/';
}
return $result;
}
return false;
}
The problem is that it runs too slow. My page sometimes loads 7-8 seconds. I suspect this query running 2 times + similar query gathering latest comments slows down my page.
I have a bad feeling about queries inside the loop. How can I avoid that?
The structure of my table is:
users (id, username, mail ...
user_info ( user_id, name, surname
public_posts ( id, slug, text, author(user id) ...
blog_posts ( id, slug, text ...
comments ( id, text, author, location(post_id_, section(post_table) ...
Check by expalining your Query , Go to the mysql command line and type
EXPLAIN SELECT *, FROM_UNIXTIME(date) AS timestamp FROM comments ORDER BY timestamp DESC LIMIT 5
Explain will tell you everything about the query, On its bases you can decide for the indexing also.
Make a practice to expalin every select query before using it in the code.
Plus you can also do profiling when ever you think your code is taking time. In codeigniter Profiler class is available, please go through the below link.
https://www.codeigniter.com/userguide3/general/profiling.html
Related
SELECT apntoken,deviceid,created
FROM `distribution_mobiletokens` as dm
WHERE userid='20'
and not exists (
select 1
from `distribution_mobiletokens`
where userid = '20'
and deviceid = dm.deviceid
and created > dm.created
)
What this query does is selects all mobiletokens where the user id is equal to 20 and the deviceid is the same but chooses the newest apntoken for the device.
My database looks like below.
For more information on this query, I got this answer from another question I asked here(How to group by in SQL by largest date (Order By a Group By))
Things I've Tried
$mobiletokens = $em->createQueryBuilder()
->select('u.id,company.id as companyid,user.id as userid,u.apntoken')
->from('AppBundle:MobileTokens', 'u')
->leftJoin('u.companyId', 'company')
->leftJoin('u.userId', 'user')
->where('u.status = 1 and user.id = :userid')
->setParameter('userid',(int)$jsondata['userid'])
->groupby('u.apntoken')
->getQuery()
->getResult();
//#JA - Get the list of all the apn tokens we need to send the message to.
foreach($mobiletokens as $tokenobject){
$deviceTokens[] = $tokenobject["apntoken"];
echo $tokenobject["apntoken"]."\n";
}
die();
This gives me the incorrect response of
63416A61F2FD47CC7B579CAEACB002CB00FACC3786A8991F329BB41B1208C4BA
9B25BBCC3F3D2232934D86A7BC72967A5546B250281FB750FFE645C8EB105AF6
latestone
Any help here is appreciated!
Other Information
Data with SELECT * FROM
Data after using the SQL I provided up top.
You could use a subselect created with the querybuilder as example:
public function selectNewAppToken($userId)
{
// get an ExpressionBuilder instance, so that you
$expr = $this->_em->getExpressionBuilder();
// create a subquery in order to take all address records for a specified user id
$sub = $this->_em->createQueryBuilder()
->select('a')
->from('AppBundle:MobileTokens', 'a')
->where('a.user = dm.id')
->andWhere('a.deviceid = dm.deviceid')
->andWhere($expr->gte('a.created','dm.created'));
$qb = $this->_em->createQueryBuilder()
->select('dm')
->from('AppBundle:MobileTokens', 'dm')
->where($expr->not($expr->exists($sub->getDQL())))
->andWhere('dm.user = :user_id')
->setParameter('user_id', $userId);
return $qb->getQuery()->getResult();
}
I did this for now as a temporary fix, not sure if this is best answer though.
$em = $this->em;
$connection = $em->getConnection();
$statement = $connection->prepare("
SELECT apntoken,deviceid,created
FROM `distribution_mobiletokens` as dm
WHERE userid=:userid
and not exists (
select 1
from `distribution_mobiletokens`
where userid = :userid
and deviceid = dm.deviceid
and created > dm.created
)");
$statement->bindValue('userid', $jsondata['userid']);
$statement->execute();
$mobiletokens = $statement->fetchAll();
//#JA - Get the list of all the apn tokens we need to send the message to.
foreach($mobiletokens as $tokenobject){
$deviceTokens[] = $tokenobject["apntoken"];
echo $tokenobject["apntoken"]."\n";
}
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 am very confused about this (returning false):
$sql = "SELECT * from tbl_user WHERE group = 'abc'";
$res = mysql_query($sql);
if(mysql_num_rows($res) > 0) {
$response = array('status' => '1');
} else {
$response = array('status' => '0'); // ---> what I get back
die("Query failed");
}
...despite the fact the field group is present in mySQL database. Even more strange is that the following return the value of group:
$SQL = "SELECT * FROM tbl_user";
$result = mysql_query($SQL);
while ($db_field = mysql_fetch_assoc($result)) {
print $db_field['group']; // ---> returns 'abc'
When I execute a WHERE clause with every other fields of my table excepting group (for example WHERE name = 'ex1' AND ID=1 AND isAllowed=0 (and so on...), everything is fine. As soon as I insert group = 'abc', I get nothing...
This makes me mad. If anyone could help... (I am running a local server with MAMP).
Thanks a lot!
The issue is that group is a reserved word in SQL.
For MySql you need to escape it with backticks
`group`
So your query would be
$sql = "SELECT * from tbl_user WHERE `group` = 'abc'";
I'm trying to output the actual SQL queries to the screen. I've added the following route:
// Display all SQL executed in Eloquent
Event::listen('illuminate.query', function($query)
{
var_dump($query);
});
This works mostly, but some values come out as question marks:
select DATE_FORMAT(DATE(`created_at`),'%b %d') as `date`, created_at, COUNT(*) as `count`
from `contacts`
where `created_at` > ? and `list_name` = ? or `list_name` = ? or `list_name` = ?
group by `date`
order by `created_at` asc
Is there a way to get the full query to output the actual values I'm dynamically adding, rather than unhelpful '?' characters?
Yes, you can use this code:
Event::listen(
'illuminate.query',
function ($sql, $bindings, $time) {
$sql = str_replace(array('%', '?'), array('%%', "'%s'"), $sql);
$full_sql = vsprintf($sql, $bindings);
file_put_contents(storage_path() . DIRECTORY_SEPARATOR . 'logs'
. DIRECTORY_SEPARATOR . 'sql_log.sql', $full_sql . ";\n",
FILE_APPEND);
}
);
In mine I save output to file in local environment, you can of course display this query on screen.
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!