grouping by non-database field - mysql

How can I group a query result by a field that is not saved in the database.
For example I want to group the result by duration which is came from subtraction of start time and end time.
here is how i find out the duration
date1= $row_TicketRS['CloseDate'];
$date2 = $row_TicketRS['OpenDate'];
$diff = abs(strtotime($date2) - strtotime($date1));
$days = floor(($diff - $years * 365*60*60*24 - $months*30*60*60*24)/ (60*60*24));
if ( $days > 0)
{
$time1 = $row_TicketRS['OpenTime'];
$time2= $row_TicketRS['CloseTime'];
$t1=($time1);
$t2=($time2);
$end=('14:30');
$start=('07:30');
$n = $end- $t1;
$n2 = $t2- $start;
$Hours2 = floor(($n+$n2)+(($days-1)*7));
echo $Hours2.' Hours';
but know i do not know how to add it to the query
here is my query
$strQuery = "SELECT count(`ticket`.TicketID) as TotOutput, department.`DeptName` FROM `ticket`, `user`, department where ticket.OwnerID = user.EmpNo and user.`DepartmentID` = department.`DepartmentID` and OpenDate between'".$DateFrom."' And '".$DateTo."'"

It'd be better to have details, but a derived table/inline view would allow you to group by a computed value:
SELECT x.duration,
COUNT(*)
FROM (SELECT t.col,
t.end_time - t.start_time AS duration
FROM YOUR_TABLE t) x
GROUP BY x.duration

How about adding that computed value to the query with an alias like this:
SELECT some_fields, end - start AS duration FROM table ORDER BY duration

dont put alias for hidden column , use directly
exmaple:
SELECT id, FLOOR(value/100)
FROM tbl_name
GROUP BY id, FLOOR(value/100);
Reference
MySQL permits expressions in GROUP BY
clauses, so the alias is unnecessary:

Related

database query to get lowest price based on last crawel date

I would like to get lowest price of product based on last crawled dates by various resellers. My current function is very basic, it gets me lowest price from table without considering reseller ids and crawled timestamps.
I've rough idea that we can SELECT * FROM "custom_data_table" and process the data using php. Please have a look at attachment for further clarification.
function get_lowest_price($table_id) {
global $wpdb;
$table_prices = $wpdb->get_results(
$wpdb->prepare(
"SELECT price FROM `custom_data_table` WHERE tableid= %d"
,$table_id)
);
if (!empty($table_prices) && $table_prices !== NULL)
return rtrim(min($table_prices)->price, '00');
}
The right query here is:
SELECT price
FROM custom_data_name cdn, (
SELECT MAX(crawled) AS maxCrawled, resellerid
FROM custom_data_name
GROUP BY resellerid
) cdnFiltered
WHERE cdn.crawled = cdnFiltered.maxCrawled AND
cdn.resellerid = cdnFiltered.resellerid AND
tableid = %d;
Try this:
SELECT B.price
FROM (SELECT resellerid, MAX(crawled) max_crawled
FROM custom_data_table
GROUP BY resellerid) A
JOIN custom_data_table B
ON A.resellerid=B.resellerid AND A.max_crawled=B.crawled;
Maybe use ORDER BY crawled and LIMIT 1

Subquery returned more than 1 value.4...Different query

Hello I have this query that i am trying to execute and i keep getting this error "Subquery returned more than 1 value. This is not permitted when the subquery follows =, !=, <, <= , >, >= or when the subquery is used as an expression.", Kindly help please.
DECLARE #NUMCOUNT BIT
Select #NUMCOUNT = (SELECT
CASE WHEN
(SELECT COUNT(R5REQUISLINES.RQL_REQ)
WHERE R5REQUISLINES.RQL_STATUS IN ('A')
) IN
(SELECT COUNT(R5REQUISLINES.RQL_REQ)
WHERE R5REQUISLINES.RQL_STATUS IN ( 'A','C') ) THEN 1 else 0 END AS NUMCOUNT1
FROM R5REQUISLINES JOIN
R5REQUISITIONS ON R5REQUISLINES.RQL_REQ = R5REQUISITIONS.REQ_CODE
GROUP BY R5REQUISLINES.RQL_REQ, R5REQUISITIONS.REQ_CODE,R5REQUISLINES.RQL_STATUS
)
IF #NUMCOUNT = '1'
begin
UPDATE R5REQUISITIONS
SET R5REQUISITIONS.REQ_STATUS = 'CP'
end
Ok, it sounds like what you actually want to do is update R5REQUISITIONS when there is no RQL_STATUS = 'C' in R5REQUISLINES, since you said you want to count the records where the RQL_STATUS is A and where it's A or C, and then do the update if the counts are the same.. You can greatly simplify this task with the following query:
UPDATE r5
SET r5.REQ_STATUS = 'CP'
FROM R5REQUISITIONS r5
WHERE NOT EXISTS (SELECT 1 FROM R5REQUISLINES r5q WHERE r5q.RQL_REQ = r5.REQ_CODE AND r5q.RQL_STATUS = 'C')
Your 'SELECT CASE' is returning more than 1 record, so it can't be assigned to #NUMBER. Either fix the sub-query to only return the record your looking for or hack it to return only 1 with a 'LIMIT 1' qualification.
I don't know what your data looks like so I can't tell you why your case subquery returns more records than you think it should.
Try running this and see what it returns, that will probably tell you wall you need to know:
SELECT
CASE WHEN
(SELECT COUNT(R5REQUISLINES.RQL_REQ)
WHERE R5REQUISLINES.RQL_STATUS IN ('A')
) IN
(SELECT COUNT(R5REQUISLINES.RQL_REQ)
WHERE R5REQUISLINES.RQL_STATUS IN ( 'A','C')
)
THEN 1
ELSE 0
END AS NUMCOUNT1
FROM R5REQUISLINES JOIN
R5REQUISITIONS ON R5REQUISLINES.RQL_REQ = R5REQUISITIONS.REQ_CODE
GROUP BY R5REQUISLINES.RQL_REQ, R5REQUISITIONS.REQ_CODE,R5REQUISLINES.RQL_STATUS
If there is more than 1 row returned, that's where your problem is.

ORDER BY clause constrained by a sub-selection in another table

I have kind of a edge-case while working on a WordPress project. I am using Advanced Custom Fields to store metadata about posts, which is stored in a "postmeta" table (whereas posts are stored in a "post" table; here prefixed by "otca_").
The posts here are events, which feature a mandatory evt_date and may feature a evt_date_fin ("fin" stands for "end" in French, sorry about the lame naming convention).
My goal is to select a range of events, keeping only those featuring a evt_date set in the future OR a evt_date_fin set in the future (in the latter case, no matter the evt_date), while ordering by evt_date, so as to display them in a paginated, sorted way.
This is what I came up with:
$today = date('Ymd');
$perPage = 12;
$offset = $perPage * ($paged-1); // $paged equals 1, 2, … n (the current page)
$querystr = "
SELECT SQL_CALC_FOUND_ROWS * FROM otca_posts AS post
INNER JOIN otca_postmeta AS meta ON (post.ID = meta.post_id)
WHERE post.post_type = 'agenda'
AND post.post_status = 'publish'
AND (
(meta.meta_key = 'evt_date' AND CAST(meta.meta_value AS CHAR) >= '". $today ."')
OR (meta.meta_key = 'evt_date_fin' AND CAST(meta.meta_value AS CHAR) >= '". $today ."')
)
ORDER BY (meta.meta_key = 'evt_date' AND CAST(meta.meta_value AS CHAR)) ASC
LIMIT ". $perPage ." OFFSET ". $offset;
$evts = $wpdb->get_results($querystr);
$total = $wpdb->get_var('SELECT FOUND_ROWS()');
// then looping over the $evts and using $perPage / $total to build the pagination links
So, for a given post stored in otca_post, there are several records in the otca_postmeta table referencing this post (using post_id), which differ by their meta_key / meta_value pairs (one pair for evt_date, another for evt_date_fin). I use them to filter out posts in the query, which works fine.
The ORDER BY clause does not actually works though.
I would like to know how I could make it so that the posts are ordered by evt_date, a piece of information stored in otca_postmeta; evt_date is not a row, but rather a value stored in the row "meta_key", which means I need to perform a sub-selection somehow in order to… order.
Thank you.
I do this fairly often in my WordPress plugins - you need to join the posts table to the postmeta table for each of the meta_key's that you care about, in this case "evt_date" and "evt_date_fin". Once you have joined them you can use them in the WHERE clause to compare to DATE(CURRENT_TIMESTAMP). Using the MySql function STR_TO_DATE() will convert the strings stored in the meta_value to a DATE datatype - this example assumes you use a Y-m-d format.
$perPage = 12;
$offset = $perPage * ($paged-1);
// create the SQL query by joining posts to postmeta
$querystr = <<<SQL
SELECT SQL_CALC_FOUND_ROWS
p.*,
STR_TO_DATE(s.meta_value, '%Y-%m-%d') AS start_date,
STR_TO_DATE(e.meta_value, '%Y-%m-%d') AS end_date
FROM otca_posts AS p
-- join postmeta for the start
JOIN otca_postmeta AS s ON p.ID = s.post_id AND s.meta_key = 'evt_date'
-- join postmeta for the end
JOIN otca_postmeta AS e ON p.ID = e.post_id AND e.meta_key = 'evt_date_fin'
WHERE
-- is the start greater than or equal to today?
STR_TO_DATE(s.meta_value, '%Y-%m-%d') >= DATE(CURRENT_TIMESTAMP) OR
-- or is the end greater than or equal to today?
STR_TO_DATE(e.meta_value, '%Y-%m-%d') >= DATE(CURRENT_TIMESTAMP)
-- order the results by the start, then the end, then the post title
ORDER BY start_date, end_date, p.post_title
-- paginate the results
LIMIT $perPage OFFSET $offset
SQL;
// get posts that match
$evts = $wpdb->get_results( $querystr );
// get the total number of results
$total = $wpdb->get_var( 'SELECT FOUND_ROWS()' );

Group by changing boolean value

Hi i have the following SQL question:
SELECT station_id, filling_station_status,date_created ,
case when filling_station_status="FREE" then 0
else 1 end as status
FROM efahrung.electric_station_time_status
where station_id=11
In my table have a column filling_station_status.
It can be "FREE" or "IN_USE".
I want to group elements so, that if the filling_station_status is changed (from "FREE" to "IN_USE") it will create a date range in my case, date_created.
In the next change again from ("IN_USE" to "FREE") it creates a new date range.
Thanks for a suggestions.
If you just need SQL query to generate date range in output, then try this:
Select s.station_id,
Coalesce(e.filling_station_status, s.filling_station_status) fillingStationStatus,
case e.filling_station_status
when "FREE" then 0 else 1 end status,
s.date_created startDate,
e.date_created endDate
From efahrung.electric_station_time_status s
Left Join efahrung.electric_station_time_status e
On e.station_id = s.station_id
and s.filling_station_status = 'IN_USE'
and e.filling_station_status = 'FREE'
and e.date_created =
(Select Min(date_created)
From efahrung.electric_station_time_status
Where station_id = s.station_id
and date_created > s.date_created)

Simplify sql query to obtain one line per id

I have a multi-table SQL query.
My need is: The query should I generate a single line by 'etablissement_id' ... and all information that I want to be back in the same query.
The problem is that this query is currently on a table where "establishment" may have "multiple photos" and suddenly, my query I currently generates several lines for the same id...
I want the following statement - LEFT JOINetablissementContenuMultimediaON etablissement.etablissement_id = etablissementContenuMultimedia.etablissementContenuMultimedia_etablissementId - only a single multimedia content is displayed. Is it possible to do this in the query below?
Here is the generated query.
SELECT DISTINCT `etablissement`. * , `etablissementContenuMultimedia`. * , `misEnAvant`. * , `quartier`. *
FROM `etablissement`
LEFT JOIN `etablissementContenuMultimedia` ON etablissement.etablissement_id = etablissementContenuMultimedia.etablissementContenuMultimedia_etablissementId
LEFT JOIN `misEnAvant` ON misEnAvant.misEnAvant_etablissementId = etablissement.etablissement_id
LEFT JOIN `quartier` ON quartier_id = etablissement_quartierId
WHERE (
misEnAvant_typeMisEnAvantId =1
AND (
misEnAvant_dateDebut <= CURRENT_DATE
AND CURRENT_DATE <= misEnAvant_dateFin
)
)
AND (
etablissement_isActive =1
)
ORDER BY `etablissement`.`etablissement_id` ASC
LIMIT 0 , 30
Here is the code used ZF
public function find (){
$db = Zend_Db_Table::getDefaultAdapter();
$oSelect = $db->select();
$oSelect->distinct()
->from('etablissement')
->joinLeft('etablissementContenuMultimedia', 'etablissement.etablissement_id = etablissementContenuMultimedia.etablissementContenuMultimedia_etablissementId')
->joinLeft('misEnAvant', 'misEnAvant.misEnAvant_etablissementId = etablissement.etablissement_id')
->joinLeft('quartier', 'quartier_id = etablissement_quartierId ')
->where ('misEnAvant_typeMisEnAvantId = 1 AND (misEnAvant_dateDebut <= CURRENT_DATE AND CURRENT_DATE <= misEnAvant_dateFin) ')
->where ('etablissement_isActive = 1')
->order(new Zend_Db_Expr('RAND()'));
$zSql = $oSelect->__toString();
if(isset($_GET['debug']) AND $_GET['debug'] == 1)
echo $zSql ;
//die();
$oResultEtablissement = $db->fetchAll($oSelect);
return $oResultEtablissement ;
}
Can you help me?
Sincerely,
If you are looking to have only one of the media displayed out of many regardless of which it may be then you can just add a limit to the query? After that you can tweak the query for ASCending or DESCending perhaps?
Is this query supposed to have images (or image as it were) for one establishment, or one image each for each active establishment? I see you have a limit 0,30 which means you're likely paginating....
If the result you want is a search for only one establishment, and the first image it comes to would work fine .. just use "limit 1" and you'll only get one result.
I took the time to redo the whole model of the database ... and now it works. There was no solution for a system as flawed