I'm developing an sql query that can join two table and it returns some results.
I have 2 tables in first table i save my order and in another table save my like information .
I want to show to user picture from order table that, user doesn't like picture yet . I use this query
SELECT amg_order.*
FROM amg_order
LEFT OUTER JOIN amg_like ON amg_like.order_id=amg_order.order_id
AND amg_like.user_id=:user_id
WHERE amg_order.status = '1'
AND amg_order.user_id != :user_id
AND (amg_like.user_id != :user_id || amg_like.user_id is null)
ORDER BY amg_order.likeType DESC, RAND()
This query return correct result but when like information be over 15000 time to execution this query has been 6 seconds .
Does anyone has any idea to reduce this time ?
I'm sorry my English is so bad :)
You can try following query. This will of course reduce some of your execution time. You can specify fields name instead of * sign in your select statement.
Here is updated query:
SELECT amg_order.* FROM amg_order
LEFT JOIN amg_like ON amg_order.order_id = amg_like.order_id
WHERE amg_order.status= '1' AND amg_order.user_id != :user_id AND (amg_like.user_id != :user_id || amg_like.user_id is null)
ORDER BY amg_order.likeType DESC LIMIT 10;
Related
I have a query regarding join . Basically there are two tables product and product_boost . The table product_boost has the product_id as foreign key which is also in product table .
I want to get the data using join which is available in both the tables, and if not only data from first table will come.
I am using right outer join, here is my query
SELECT * FROM `vefinder_product`
RIGHT OUTER JOIN `vefinder_product_boost` ON `vefinder_product_boost`.`product_id`=`vefinder_product`.`product_id`
WHERE `vefinder_product`.`status` = 1
AND `vefinder_product`.`post_type` != 5
AND `vefinder_product`.`country` IN('348')
AND `vefinder_product`.`product_stock` >0
AND `vefinder_product`.`product_in_stock` = 1
AND `vefinder_product_boost`.`target_age_from` >= 20
AND `vefinder_product_boost`.`target_age_to` <= 40
ORDER BY `vefinder_product`.`is_boosted` DESC,
`vefinder_product`.`is_sponsered` DESC,
`vefinder_product`.`created_date` DESC LIMIT 21
How can i achive the desired thing , because this is not working. I am using codeigniter php.
Use Left join instead, if you want to get all the data from first (leftmost) table.
Any Where conditions on tables other than the first table (leftmost), should be shifted to ON condition in Left Join. Otherwise, Where would filter out unmatched rows also (null in the right side tables).
Try the following instead:
SELECT *
FROM `vefinder_product`
LEFT OUTER JOIN `vefinder_product_boost`
ON `vefinder_product_boost`.`product_id`=`vefinder_product`.`product_id` AND
`vefinder_product_boost`.`target_age_from` >= 20 AND
`vefinder_product_boost`.`target_age_to` <= 40
WHERE `vefinder_product`.`status` = 1 AND
`vefinder_product`.`post_type` != 5 AND
`vefinder_product`.`country` IN('348') AND
`vefinder_product`.`product_stock` >0 AND
`vefinder_product`.`product_in_stock` = 1
ORDER BY `vefinder_product`.`is_boosted` DESC,
`vefinder_product`.`is_sponsered` DESC,
`vefinder_product`.`created_date` DESC
LIMIT 21
Use left join and put where condition in ON cluase
SELECT * FROM `vefinder_product`
left OUTER JOIN `vefinder_product_boost` ON `vefinder_product_boost`.`product_id`=`vefinder_product`.`product_id`
and `vefinder_product`.`status` = 1
AND `vefinder_product`.`post_type` != 5
AND `vefinder_product`.`country` IN('348')
AND `vefinder_product`.`product_stock` >0
AND `vefinder_product`.`product_in_stock` = 1
AND `vefinder_product_boost`.`target_age_from` >= 20
AND `vefinder_product_boost`.`target_age_to` <= 40
ORDER BY `vefinder_product`.`is_boosted` DESC,
`vefinder_product`.`is_sponsered` DESC,
`vefinder_product`.`created_date` DESC LIMIT 21
you can use third party software like SQLyog.
it is very simple for join query just build query with UI and assign relation to that fields between tables.
in sqlyog you can get data from multiple tables not only two tables.
because i am currently using this software for time saving.
I'm having some problems with a query that finds the next ID of an orders with certain filters on it - Like it should be from a specific city, etc.
Currently it's used for a function, where it'll either spit out the previous or the next ID based on the current order. So it can either be min(id) or max(id), where max(id) is obviously faster, since it has to go through less rows.
The query is working just fine, but it's rather slow, since it's going through 123953 rows to find the ID. Is there any way I could optimize this?
Function example:
SELECT $minmax(orders.orders_id) AS new_id FROM orders LEFT JOIN orders_status ON orders.orders_status = orders_status.orders_status_id $where_join WHERE orders_status.language_id = '$languages_id' AND orders.orders_date_finished != '1900-01-01 00:00:00' AND orders.orders_id $largersmaller $ordersid $where;
Live example
SELECT min(orders.orders_id)
FROM orders
LEFT JOIN orders_status ON orders.orders_status = orders_status.orders_status_id
WHERE orders_status.language_id = '4'
AND orders.orders_date_finished != '1900-01-01 00:00:00'
AND orders.orders_id < 4868771
LIMIT 1
so concluding:
SELECT orders.orders_id
FROM orders
JOIN orders_status ON orders.orders_status = orders_status.orders_status_id
WHERE orders_status.language_id = '4'
AND orders.orders_date_finished != '1900-01-01 00:00:00'
AND orders.orders_id < 4868771
ORDER BY orders.orders_id ASC
LIMIT 1
Extra:
to get the MAX value, use DESC where ASC is now.
And looking at your question: be sure to escape the values like $language_id etcetera. I suppose they could come from some html form?
(or use prepared statements)
Can anyone tell me how to make this query faster?
$session_id = '000000000015';
$start = 0;
$finish = 30;
try {
$stmt = $conn->prepare("SELECT TOPUSERS.ID, TOPUSERS.USERNAME, TOPUSERS.NAME, TOPUSERS.NAME2, TOPUSERS.PHOTO, TOPUSERS.FB_USERID, TOPUSERS.IMAGE_TYPE, TOPUSERS.TW_USERID, TOPUSERS.TW_PHOTO,
COALESCE((SELECT COUNT(USERS_BUCKETS.ID) FROM USERS_BUCKETS WHERE USERS_BUCKETS.USERID=TOPUSERS.ID),0) AS NUM_ALL,
COALESCE((SELECT SUM(CASE WHEN USERS_BUCKETS.STATUS='Completed' THEN 1 ELSE 0 END) FROM USERS_BUCKETS WHERE USERS_BUCKETS.USERID=TOPUSERS.ID),0) AS NUM_DONE,
COALESCE((SELECT COUNT(USERS_LIKES.ID) FROM USERS_LIKES WHERE USERS_LIKES.USERID=TOPUSERS.ID),0) AS NUM_LIKES,
(SELECT USERS_BUCKETS.BUCKETID FROM USERS_BUCKETS WHERE USERS_BUCKETS.USERID=TOPUSERS.ID ORDER BY USERS_BUCKETS.DATE_MODIFIED DESC LIMIT 1) AS RECENT_BUCKET,
(SELECT BUCKETS_NEW.BUCKET_NAME FROM BUCKETS_NEW WHERE BUCKETS_NEW.ID=RECENT_BUCKET) AS REC,
COALESCE((SELECT COUNT(ID) FROM FOLLOW WHERE FOLLOW.USER_ID=TOPUSERS.ID),0) AS FOLLOWING,
COALESCE((SELECT COUNT(ID) FROM FOLLOW WHERE FOLLOW.FOLLOW_ID=TOPUSERS.ID),0) AS FOLLOWERS,
(SELECT IF(TOPUSERS.NAME = '',0,1) + IF(TOPUSERS.BIO = '',0,1) + IF(TOPUSERS.LOCATION = '',0,1) + IF(TOPUSERS.BIRTHDAY = '0000-00-00',0,1) + IF(TOPUSERS.GENDER = '',0,1)) as COMPLETENESS,
CASE WHEN ? IN (SELECT USER_ID FROM FOLLOW WHERE FOLLOW_ID = TOPUSERS.ID) THEN 'Yes' ELSE 'No' END AS DO_I_FOLLOW_HIM
FROM TOPUSERS
LEFT JOIN FOLLOW ON TOPUSERS.ID = FOLLOW.FOLLOW_ID
LEFT JOIN USERS_BUCKETS ON USERS_BUCKETS.USERID=TOPUSERS.ID
LEFT JOIN BUCKETS_NEW ON BUCKETS_NEW.ID=USERS_BUCKETS.BUCKETID
WHERE NOT TOPUSERS.ID = ?
GROUP BY TOPUSERS.ID ORDER BY TOPUSERS.RANDOM, TOPUSERS.USERNAME LIMIT $start, $finish");
When I run this in a browser it takes about 7 seconds to load. Without a few lines (the COALESCE in the middle, the two SELECTS above and the line below them) the time is reduced to 3-4 seconds.
The result of the query is a list of people with names, profile picture and some data.
TL,DR: you need to rewrite the query.
You need to rewrite your query to make it more efficient. I had to rewrite a similar query at work last week and here is what I have done.
The structure of your query should look like this to be efficient:
select ...
...
from ...
join ...
where ...
what you have now is something like:
select ...
inner select
inner select
from ...
join ...
where ...
That's the inner selects that kill your query. You need to find a way to move the inner select into the from section. Especially that you already query the tables.
What you need to understand is that your inner selects run for every records you have. So if you have 10 records, it would be alright (speed wise). But with hundred or thousand of records, it would be very slow.
If you want more information on your query run it with the explain keyword in from of it.
I`m trying to query my database with 4 queries, each query will give me the number of rows that I need but I faced with but I notice when I do the query on the server that strong, everything works fast (relatively), but if I make it a relatively simple server that I deserve the maximum working time (30 seconds, the limit execution time(PHP)).
my while loop works with list of MokedCcode each MokedCcode goes into the queries and go to the next MokedCcode.
Notes :
1) I know it will be proportional to the number of MokedCcode-s.
2) I need to increase the execution time limit?
1) there is more efficient way to make those queries? maybe I dont use the mysql features right.
for example the first query called $emerg, this query need to give me the number of rows between dates, where WCODE have priority 1 and it has to be match of MokedCcode on both tables ( t and e ).
$emerg = mysql_num_rows(mysql_query("SELECT t.*,e.DISCODE,e.AREA,e.COLOR,e.PRIORITY FROM $tbl_name AS t
LEFT JOIN eventcodes AS e ON t.MokedCcode = e.MokedCcode AND t.WCODE=e.WCODE
WHERE (t.MokedCcode='$MokedCcode' ) AND e.PRIORITY='1'
AND t.ndate BETWEEN '$start' AND '$end' ORDER By `id` DESC "));
In addition I added the 3 more queries, I would like to get some advice how to make it faster Or I dont have any choice and keep it like that.
The 3 other queries:
$regular = mysql_num_rows(mysql_query("SELECT t.*,e.DISCODE,e.AREA,e.COLOR,e.PRIORITY FROM $tbl_name AS t
LEFT JOIN eventcodes AS e ON t.MokedCcode = e.MokedCcode AND t.WCODE=e.WCODE
WHERE (t.MokedCcode='$MokedCcode' ) AND e.PRIORITY!='1'
AND t.ndate BETWEEN '$start' AND '$end' ORDER By `id` DESC "));
$regHandled = mysql_num_rows(mysql_query("SELECT t.*,e.DISCODE,e.AREA,e.COLOR,e.PRIORITY FROM $tbl_name AS t
LEFT JOIN eventcodes AS e ON t.MokedCcode = e.MokedCcode AND t.WCODE=e.WCODE
WHERE (t.MokedCcode='$MokedCcode' ) AND e.PRIORITY!='1'
AND t.EventHandling!='0' AND t.ndate BETWEEN '$start' AND '$end' ORDER By `id` DESC "));
$emergHandled = mysql_num_rows(mysql_query("SELECT t.*,e.DISCODE,e.AREA,e.COLOR,e.PRIORITY FROM $tbl_name AS t
LEFT JOIN eventcodes AS e ON t.MokedCcode = e.MokedCcode AND t.WCODE=e.WCODE
WHERE (t.MokedCcode='$MokedCcode' ) AND e.PRIORITY='1'
AND t.EventHandling!='0' AND t.ndate BETWEEN '$start' AND '$end' ORDER By `id` DESC "));
I didn't exactly understand what you are trying to achieve.
If you just want the count Why are you selecting all the rows? cant you use COUNT() MySQL function? It is always slow to get all the data to your script and then count the rows.
Even if you want to select all those columns, try using t.field1, t.field2, ... instead of t.*
This is a more detailed question as my previous attempt wasn't clear enough. I'm new to MySQL and have no idea about the best way to do certain things. I'm building a voting application for images and am having trouble with some of the finer points of MySQL
My db
_votes
id
voter_id
image_id
_images
id
file_name
entrant_id
approved
_users
id
...
Basically I need to do the following:
tally up all votes that are approved
return the top 5 with the most votes
check if the user has voted on each of these 5 (return Boolean) from another table
I've tried variations of
SELECT i.id, i.file_name, i.total_votes
FROM _images i WHERE i.approved = 1
CASE WHEN (SELECT count(*) from _votes v WHERE v.image_id = i.id AND v.voter_id = ?) > 0 THEN '1' ELSE '0' END 'hasvoted'
ORDER BY i.total_votes DESC LIMIT ".($page*5).", 5
is that something I should try and do all in one query?
This query was working fine before I tried to add in the 'hasvoted' boolean:
SELECT id, file_name, total_votes FROM _images WHERE approved = 1 ORDER BY total_votes DESC LIMIT ".($page*5).", 5
At the moment I'm also storing the vote count in the _images table and I know this is wrong, but I have no idea about how to tally the votes by image_id and then order them.
Let me give this a shot to see if I understand your question:
SELECT i.*,(SELECT COUNT(*) FROM _votes WHERE i.id = image_id) AS total_votes, (SELECT count(*) from _votes where i.id = image_id and user_id = ?) as voted FROM _images AS i WHERE i.approved = 1