I have a many-to-many relationship between two tables: person and favorites. I have three columns:
person_id int(8)
favorites_id int(8)
is_main_favorite enum('y','n')
as:
person_id | favorite_id | is_main_favorite
2 | 1 | 'y'
2 | 2 | 'n'
3 | 1 | 'n'
3 | 2 | 'n'
1 | 1 | 'y'
1 | 2 | 'y'
I'm using PHP and MySQL.
How I can retrieve person_id that have (favorite_id 1 and 2 together) and order the result by person id that have more is_main_favorite ='y', so the result should be as:
person_id
1 (because he has favorite_id 1 and 2 and have two is_main_favorite = 'y')
2 (because he has favorite_id 1 and 2 and have one is_main_favorite = 'y')
Probably something similar to this:
SELECT
a.person_id
FROM
table AS a,
table AS b
WHERE
a.person_id = b.person_id AND
a.favorite_id = 1 AND
b.favorite_id = 2
ORDER BY
( IF( a.is_main_favorite = "y", 1, 0 )
+
IF( b.is_main_favorite = "y", 1, 0 ) ) DESC
By the way: You may want to store 1/0 instead of y/n in the database so that you won't need the IF call
Solution
SELECT `person_id`
FROM `persons`
LEFT JOIN `favorites` AS `one`
ON `favorites`.`person_id` = `persons`.`person_id`
LEFT JOIN `favorites` AS `two`
ON `favorites`.`person_id` = `persons`.`person_id`
WHERE `one`.`favorite_id` = ?
AND `two`.`favorite_id` = ?
ORDER BY (
IF(`one`.`is_main_favorite` = "y", 1, 0)
+
IF(`two`.`is_main_favorite` = "y", 1, 0)
) DESC
How it works
First, the favorites table is joined to the persons table twice, each as it's own table (one and two). Then, both favorite_ids are checked to see if they exist. If they are both present, the row is included in the result set, and sorted by the count of is_main_favorite (2 if two "y", 1 if one "y", or 0).
SELECT p.person_id
FROM person AS p, favorites AS f1, favorites AS f2
WHERE p.person_id = f1.person_id AND
p.person_id = f2.person_id AND
f1.favorite_id IS NOT NULL AND
f2.favorite_id IS NOT NULL
ORDER BY
( IF( f1.is_main_favorite = "y", 1, 0 )
+
IF( f2.is_main_favorite = "y", 1, 0 ) ) DESC
Related
I have 2 tables in mysql database.
a) company
cid company_name
===================
1 AstraZeneca
2 Emirates
3 Development Bank of Singapore
4 Royal Copenhagen
5 xxx
6 xxx
2) history
hid user_id view_id is_save mark_as view date
==============================================================
1 2 2 0 3 2016-08-25 22:06:12
2 3 3 1 3 2016-08-25 22:07:12
3 3 3 0 1 2016-08-25 22:08:12
4 3 2 0 1 2016-08-25 22:09:12
5 2 4 0 1 2016-08-25 22:10:12
6 4 5 0 1 2016-08-25 22:11:12
7 4 6 0 1 2016-08-25 22:12:12
This view_id is containing cid value.
Now, always I want to show latest 5 company_name from company table as ascending order based on history table view_id.
For that purpose I am doing following query. But company_name is not showing either ASC or DESC order
Here is the query :
$getViewID3 = mysqli_query($link, "SELECT view_id, hid, is_save FROM history WHERE user_id = '$user_id' AND mark_as = 3 GROUP BY view_id ORDER BY view_date DESC LIMIT 5 ");
if(mysqli_num_rows($getViewID3) > 0 ) {
while( $fetchViewId3 = mysqli_fetch_array($getViewID3) ) {
$viewid3 = (int) $fetchViewId3['view_id'];
$hid3 = (int) $fetchViewId3['hid'];
$is_save3 = (int) $fetchViewId3['is_save'];
$getCompany = mysqli_query($link, "SELECT company_name FROM company WHERE cid = '$viewid3' ORDER BY company_name DESC");
if(mysqli_num_rows($getCompany) > 0 ) {
while ($fetchCompany2 = mysqli_fetch_array($getCompany)) {
$cName = htmlspecialchars($fetchCompany2['company_name']);
$url_link = "{$url}company.php?cid=$viewid";
if($is_save3 == 1) {
$checked = 'checked = "checked"';
} else {
$checked = '';
}
echo "<li><a onClick='window.document.location=\"$url_link\"'> $cName </a> <input type='checkbox' class='data_save' $checked data-hid='$hid' data-saveid='$viewid3' name='save_history'></li>";
}
}
}
For example : Result is showing : A, E, D, R, L letter order.
It's should be show : A, D, E, L, R letter Order from company_name column.
If I didn't misunderstand:
SELECT
C.company_name
FROM company C
INNER JOIN
(
SELECT
view_id,
MAX(view_date) max_view_date
FROM history
WHERE is_save IN (0,1) AND mark_as = 3
GROUP BY view_id
ORDER BY max_view_date DESC
LIMIT 5
) AS t
ON C.cid = t.view_id
ORDER BY C.company_name ASC;
Note:
Since you want latest 5 companies the following query will put the last view_date beside the view_id.
Now if you sort these rows based on descending order of max_view_date and later limit the result to 5 then you will get at most five view_ids from the inner query.
Later a simple INNER JOIN between this result set and your company table will finish the job.
Sorry, sorting the final result in ascending order of company name will finish the job.
EDIT:
In order to get all the columns from history table and company_name column from company table:
SELECT
C.company_name,
t.*
FROM company C
INNER JOIN
(
SELECT
history.*
FROM history
INNER JOIN
(
SELECT
view_id,
MAX(view_date) max_view_date
FROM history
WHERE is_save IN (0,1) AND mark_as = 3
GROUP BY view_id
ORDER BY max_view_date DESC
LIMIT 5
) AS latestHistory
ON history.view_id = latestHistory.view_id AND history.view_date = latestHistory.max_view_date
) AS t
ON C.cid = t.view_id
ORDER BY C.company_name ASC;
this is my table
row | car_id | car_model | car_features |
1 1 CAR 1 Features 1
2 2 CAR 2 Features 2
3 2 CAR 2 Features 3
and i want to make it like
row | car_id | car_model | car_features |
1 1 CAR 1 Features 1
2 2 CAR 2 Features 2, Features 3
and this is my php mysql script:
<?php
$con = mysql_connect("localhost", "root", "root");
mysql_select_db("car", $con);
$format = mysql_query("SELECT c.* , p.*, d.*,f.* ,e.* FROM bsi_car_master c,bsi_car_type p, bsi_car_vendor d, bsi_selected_features f, bsi_car_features e WHERE c.car_type_id=p.id AND c.car_vendor_id=d.id AND c.car_id = f.car_id AND f.features_id = e.id");
$row = 1;
while($srow = mysql_fetch_array($format))
{
blah blah blah....
}
?>
Use GROUP_CONCAT with GROUP BY. Try this -
SELECT `row`, `car_id`, `car_model`, GROUP_CONCAT(`car_features`, ',')
FROM your_table GROUP BY `car_id`
SELECT car_id,car_model,GROUP_CONCAT(car_features,',')
FROM yourtable
GROUP BY car_id,car_model;
$format = mysql_query("SELECT c.* , p.*, d.*,f.* ,e.*,group_concat(`c.car_features`,',') as `carfeatures` FROM bsi_car_master c,bsi_car_type p, bsi_car_vendor d, bsi_selected_features f, bsi_car_features e WHERE c.car_type_id=p.id AND c.car_vendor_id=d.id AND c.car_id = f.car_id AND f.features_id = e.id group by c.car_id");
Hopefully, it's fairly obvious that I'm no PHP coder, but here's another way to do it, without GROUP_CONCAT()...
<?php
/*
DROP TABLE IF EXISTS my_table;
CREATE TABLE my_table
(id INT NOT NULL AUTO_INCREMENT PRIMARY KEY
,car_id INT NOT NULL
,car_model VARCHAR(12) NOT NULL
,car_features VARCHAR(20) NOT NULL
);
INSERT INTO my_table VALUES
(1 ,1 ,'CAR 1','Features 1'),
(2 ,2 ,'CAR 2','Features 2'),
(3 ,2 ,'CAR 2','Features 3');
*/
require('path/to/mysqli/connection/stateme.nts');
$query = "
SELECT id
, car_id
, car_model
, car_features
FROM my_table
ORDER
BY car_model;
";
$result = mysqli_query($db,$query);
$car_id = 0;
while($row = mysqli_fetch_assoc($result)){
if ($car_id== $row['car_id']){
echo " >".$row['car_features']."<br>\n";
} else {
echo $row['car_model']."<br>\n >".$row['car_features']."<br>\n";
$car_id = $row['car_id'];
}
} // end of while loop
/*
Outputs...
CAR 1
>Features 1
CAR 2
>Features 2
>Features 3
*/
?>
I have this table:
ID CODE WEEK SEX
1 abc 1 F
2 abc 2 M
3 xyz 3 F
4 abc 1 M
and I am using this query to filter the data:
SELECT `code`,`week`,`sex`, COUNT(`week`) as cnt
FROM `table`
WHERE `code` = "abc"
and `sex` = "F"
group by `week`
having (`week` > 0)
UNION ALL
SELECT `code`,`week`,`sex`, COUNT(`week`) as cnt
FROM `table`
WHERE `code` = "abc"
and `sex` = "M"
group by `week`
having (`week` > 0)
and this is the result:
CODE WEEK SEX cnt
abc 1 F 1
abc 1 M 1
abc 2 M 1
But now I need to show the data in this way:
CODE WEEK M F
abc 1 1 1
abc 2 1 0
So I have this query:
SELECT
`WEEK`,`CODE`,
GROUP_CONCAT(if(`SEX` = "F", `cnt`, NULL)) AS "F",
GROUP_CONCAT(if(`SEX` = "M", `cnt`, NULL)) AS "M"
FROM `temp_table`
GROUP BY `WEEK`
ORDER BY CAST(`WEEK` AS UNSIGNED)
How can I combine this 2 queries? Is there a better way to do this?
SELECT `WEEK`,`CODE`
, SUM(IF(`SEX` = "F", cnt, 0)) AS `F`
, SUM(IF(`SEX` = "M", cnt, 0)) AS `M`
FROM `table`
GROUP BY `WEEK`,`CODE`
;
I'm not sure why you were doing that strange ORDER BY, and I was pretty sure you would want to group on CODE as well. (Edit: Yes, the CAST was appropriate for the data type of week.)
If using the first query as the "source", see below:
SELECT `WEEK`,`CODE`
, SUM(IF(`SEX` = "F", 1, 0)) AS `F`
, SUM(IF(`SEX` = "M", 1, 0)) AS `M`
FROM ([original query goes in here]) `subQ`
GROUP BY `WEEK`,`CODE`
;
I'm trying to condense data that I have in my database into rows with their points tallied to see the most popular.
If I had a data table like:
`data`
item1 item2
1
1 2
1 3
1 3
2 3
And wanted the condensed version to be:
`data_sum`
item1 item2 Tally
1 2 2
1 3 3
2 3 1
How would I achieve this? I have somewhat of an idea here:
$popdata = mysql_query("SELECT * FROM data");
while($add = #mysql_fetch_array($popdata)){
$qitem1 = "SELECT * FROM data_sum WHERE item1='".$add['item1']."'";
$ritem1 = mysql_query($qitem1);
if(mysql_num_rows($ritem1) > 0){
$qitem2 = "SELECT * FROM data_sum WHERE item2='".$add['item2']."'";
$ritem2 = mysql_query($qitem2);
if (mysql_num_rows($ritem2) > 0){
$sql = "UPDATE Tally=Tally + 1 WHERE item1='".$add['item1']."' AND item2='".$add['item2']."'";
$update = mysql_query($sql);
}
else{
$sql = "INSERT INTO data_sum (item1, item2) VALUES('$item1', '$item2')";
$insert = mysql_query($sql);
}
else{
$sql = "INSERT INTO data_sum (item1, item2) VALUES('$item1', '$item2')";
$insert = mysql_query($sql);
}
Yes, I know the total tallies are one more than the rows in the first table. I want the rows with a null column to count towards both tallies with a common factor. This file is going to go through thousands of rows so I want utmost efficiency! Thanks!
All you would need to do is create a new table and then combine an INSERT statement with a GROUP BY'd SELECT statement. This would COUNT() the number of times item1 and item2 were the same and store them in the new tally'd table.
Something along the lines of:
INSERT INTO new_tally_table (item1, item2, Tally)
SELECT item1, item2, COUNT(*)
FROM table
GROUP BY item1, item2
Edit:
Actually re-read the last bit of your question. Think what you want is something like this:
SELECT item1, item2, COUNT(*)
FROM (
SELECT i1.item1, i2.item2
FROM table1 as i1
INNER JOIN (
SELECT DISTINCT item1, item2
FROM table1 WHERE item2 IS NOT NULL
) as i2 ON (i1.item1 = i2.item1)
WHERE i1.item2 IS NULL
UNION ALL
SELECT item1, item2
FROM table1
WHERE item2 IS NOT NULL
) as t
GROUP BY item1, item2
There's probably a better way of writing that though.
There may be a simpler solution, but I can't think of it...
DROP TABLE IF EXISTS my_table;
CREATE TABLE my_table
(id INT NOT NULL AUTO_INCREMENT PRIMARY KEY
,item1 INT NULL
,item2 INT NULL
);
INSERT INTO my_table (item1,item2) VALUES
(1 ,NULL),
(1 ,2),
(1 ,3),
(1 ,3),
(2 ,3);
SELECT x.item1
, x.item2
, COUNT(DISTINCT y.id)
FROM my_table x
JOIN my_table y
ON y.item1 = x.item1
AND (y.item2 = x.item2 OR y.item2 IS NULL)
AND y.id <= x.id
JOIN
( SELECT item1
, item2
, MAX(id) max_id
FROM my_table
GROUP
BY item1
, item2
) z
ON z.item1 = x.item1
AND z.item2 = x.item2
AND z.max_id = x.id
WHERE x.item2 <> 0
GROUP
BY x.id;
+-------+-------+----------------------+
| item1 | item2 | COUNT(DISTINCT y.id) |
+-------+-------+----------------------+
| 1 | 2 | 2 |
| 1 | 3 | 3 |
| 2 | 3 | 1 |
+-------+-------+----------------------+
I have a mysql query of type
select some_value FROM table WHERE (subquery) IN ( values )
which seems to be extremly slow!
I have a mysql table with orders and a second one with the corresponding processing states of them. I want now to show all orders having their last status code = 1 .
table order (id = primary key)
id | value
---+-------
1 + 10
2 + 12
3 + 14
table state (id = primary key)
id | orderid | code
---+---------+-------
1 + 1 + 1
2 + 2 + 1
3 + 2 + 2
4 + 1 + 3
5 + 3 + 1
My query is:
select order.id FROM order WHERE
( select state.code FROM state WHERE state.orderid = order.id ORDER BY state.id DESC LIMIT 0,1 ) IN ( '1' )
It takes roughly 15 seconds to process this for a single order. How to modify the mysql statement in order to speed the query procession time up?
Update
Try this one:
select s1.orderid
from state s1
left outer join state s2 on s1.orderid = s2.orderid
and s2.id > s1.id
where s1.code = 1
and s2.id is null
You may need an index on state.orderid.
SQL Fiddle Example
CREATE TABLE state
(`id` int, `orderid` int, `code` int)
;
INSERT INTO state
(`id`, `orderid`, `code`)
VALUES
(1, 1, 1),
(2, 2, 1),
(3, 2, 2),
(4, 1, 3),
(5, 3, 1)
;
Query:
select s1.orderid
from state s1
left outer join state s2 on s1.orderid = s2.orderid
and s2.id > s1.id
where s1.code = 1
and s2.id is null
Results:
| ORDERID |
|---------|
| 3 |
in this situation I think you could simply forget of order, as all information stays in state.
SELECT x.id, x.orderid
FROM state AS x
WHERE x.code =1
AND x.id = (
SELECT max( id )
FROM a
WHERE orderid = x.orderid )
Maybe would be possible to change your CRUD by putting last state directly in order table too, this would be the better