I'm doing a LEFT JOIN on three tables, where the table "time" doesn't necessarily contain any matching rows. But if no matching rows is found in that table, the linked data disappears.
SELECT
w.date AS worker_date,
w.name AS worker_name,
w.address AS worker_address,
w.zip AS worker_zip,
w.place AS worker_place,
w.phone AS worker_phone,
w.email AS worker_email,
w.company AS worker_company,
w.accessibility AS worker_accessibility,
c.date AS client_date,
c.name AS client_name,
c.address AS client_address,
c.zip AS client_zip,
c.place AS client_place,
c.phone AS client_phone,
c.email AS client_email,
c.web AS client_web,
c.contact AS client_contact,
j.date AS job_date,
j.client_id,
j.worker_id,
j.name AS job_name,
j.description AS job_description,
j.type AS job_type,
j.status AS job_status,
j.proof AS job_proof,
j.deadline AS job_deadline,
j.price AS job_price,
j.final_client AS job_final_client,
SUM(t.hours) AS time_hours
FROM
jobs AS j
LEFT JOIN (
workers AS w,
clients AS c,
time AS t
) ON (
w.id = j.worker_id AND
c.id = j.client_id AND
j.id = t.job_id
) GROUP BY
j.id;
How can I make this work?
Thank you in advance.
add
WHERE t.job_id IS NOT NULL before GROUP BY
Try Replace
SUM(t.hours) AS time_hours
to
(SELECT IFNULL(SUM(t.hours),0) FROM time WHERE time.job_id=j.job_id) AS time_hours
And remove the time from the join
I think your basic query is correct (with the join under braces)
Just replace
SUM(t.hours) AS time_hours
with
SUM(if(t.hours is NULL,0,t.hours)) AS time_hours
I am not sure if this is the problem here, but the behavior of commas vs JOINs changed after a certain MySQL version. Try this
...
FROM jobs AS j LEFT JOIN workers AS w ON w.id = j.worker_id
LEFT JOIN clients AS c c.id = j.client_id
LEFT JOIN `time` AS t ON j.id = t.job_id
...
Also modify the SUM with IFNULL as #ajreal suggests.
Related
Yes, this is an assignment. So the task was to output two columns of 'first name' and 'last name' with conditions:
-A u (B ∩ -C ∩ -(A ∩ -( B u D)))
A: All consumers that didn't shop on Monday and Friday
(time_by_day.the_day)
B: All consumers who bought 'Non-Consumable'
(product_class.product_family)
C: All consumers who bought more than 10 items
(sales_fact_1997.unit_sales) at one time (sales_fact_1997.time_id)
D: Female consumers from Canada (consumer.gender, consumer.country)
This is what I got so far
SELECT
c.fname,
c.lname
FROM
customer AS c
INNER JOIN sales_fact_1997 AS s ON c.customer_id = s.customer_id
INNER JOIN time_by_day AS t ON s.time_id = t.time_id
INNER JOIN product AS p ON s.product_id = p.product_id
INNER JOIN product_class AS pc ON p.product_class_id = pc.product_class_id
Where
NOT t.the_day in ('Monday', 'Friday') OR
(
pc.product_family = 'Non-Consumable' AND
NOT SUM(s.unit_sales) > 10 AND
NOT (
t.the_day in ('Monday', 'Friday') AND
NOT (
pc.product_family = 'Non-Consumable' OR
(c.country = 'Canada' AND c.gender = 'F')
)
)
)
GROUP BY concat(c.customer_id, s.time_id)
That ended up with an error
#1111 - Invalid use of group function
But I don't know which part of the code is wrong. I'm pretty sure that it's probably the WHERE part. But I don't know what I did wrong.
Condition C is where I'm really struggling. I manage just fine making a query of C
SELECT
t.time_id,
c.customer_id,
c.fullname,
round(SUM(s.unit_sales),0) as tot
FROM
customer as c
INNER JOIN sales_fact_1997 as s ON c.customer_id = s.customer_id
INNER JOIN time_by_day as t on s.time_id=t.time_id
GROUP BY concat(c.customer_id, s.time_id)
ORDER BY c.customer_id, t.time_id
But trying to incorporate it into the main code is hard for me.
Reading online I assume that I should probably use HAVING instead of WHERE.
I would really appreciate it if someone can point me in the right direction.
This is the database that I used.
C: All consumers who bought more than 10 items
(sales_fact_1997.unit_sales) at one time (sales_fact_1997.time_id)
You should use COUNT not SUM.
SELECT time_id,
count(*)
FROM sales_fact_1997
GROUP BY time_id
HAVING COUNT(*)>=10 ;
count(*) is not needed, I let just to show the results
Can you try if it helps:
SELECT c.lname,
c.fname
FROM customer c
INNER JOIN
(
SELECT time_id,customer_id,product_id
FROM sales_fact_1997
GROUP BY time_id,customer_id,product_id
HAVING COUNT(*)>=10
) as s on c.customer_id=s.customer_id
INNER JOIN
(
SELECT time_id,the_day
FROM time_by_day
WHERE the_day
NOT IN ('Monday','Friday')
) as t on s.time_id=t.time_id
INNER JOIN
(
SELECT product_family,product_id
FROM product_class
INNER JOIN product
on product_class.product_class_id=product.product_class_id
WHERE product_family='Non-Consumable'
) pc on s.product_id=pc.product_id
where c.country='Canada' and c.gender ='F' ;
So I'm having a slight problem with having to save price on a product in two different tables due to a few reasons. Is it possible to merge two columns into one? I know UNION exists but does it work with LEFT JOIN's?
Any pointers is much appreciated.
Best Regards
SELECT
si.id AS shop_item_id,
si.item_price,
s.logo_file_name,
p.cat_id AS category_id,
api.item_price AS api_price,
MAX(c.campaign_desc) AS campaignDesc,
MAX(c.campaign_type_id) AS campaignType,
MAX(c.shop_id) AS campaign_shop_id,
MAX(ct.image_name) AS campaignLogo
FROM
shop_item si
LEFT JOIN
shop s ON
s.id = si.shop_id
LEFT JOIN
product p ON
si.product_id = p.id
LEFT JOIN
campaign_category cc ON
cc.category_id = p.cat_id
LEFT JOIN
campaign c ON
c.id = cc.campaign_id AND
c.shop_id = si.shop_id AND
c.show_in_pricetable = 1 AND
NOW() BETWEEN c.date_from and c.date_to
LEFT JOIN
campaign_type ct ON
c.campaign_type_id = ct.id
LEFT JOIN
shop_api_item api ON
si.rel_feed_api = api.unique_id AND si.shop_id = api.shop_id
WHERE
si.`product_id` = 586 AND
s.`active_shop` = 1
GROUP BY
s.name,
si.id ,
si.item_price
ORDER BY
si.`item_price`,
si.`shop_id`,
c.`campaign_desc` DESC
It looks like you would benefit from the COALESCE() function.
SELECT
si.id AS shop_item_id,
COALESCE(si.item_price, api.item_price) AS coalesced_price,
...
COALESCE() takes multiple arguments, and returns the first argument that is not NULL.
I try to improve this query but I do not made successefully. I use a some left join and subquerys (I don't know another form) We try to get all bookings from users with certain status and the number of bookings multiples related with this booking and get from the log user the origin. The query is slow even if use a limit clausure. I Appreciate all the help can you give me.
This is the query:
SELECT DISTINCT b.uneaque_id, b.id, b.status, b.route_status, b.username, b.purpose, b.transfer, b.pickup_date, b.pickup_time, b.return_time, b.amount, b.default_location, b.start_address_route_comments, b.start_address_route, b.end_address_route_comments, b.end_address_route, u1.first_name, u1.last_name, b.transaction_Id, b.manual_payment, mr.AddressCount, lu.origin
FROM bookingdetails b
LEFT JOIN log_users lu ON lu.uneaque_id = b.uneaque_id AND lu.command_type = 'NEW BOOKING'
LEFT JOIN (
SELECT booking_id, COUNT(*) AS AddressCount FROM booking_multiple_rides GROUP BY booking_id
) mr ON b.id = mr.booking_id,
userdetails u1 WHERE b.username = u1.email
AND u1.user_status IN ('Active', 'Blocked', 'Not_Active')
AND b.default_location = 1
PD: Sorry for my english.
You have a ON b.id = mr.booking_id, userdetails u1 WHERE
you should change with a proper inner join
SELECT DISTINCT b.uneaque_id
, b.id, b.status
, b.route_status
, b.username
, b.purpose
, b.transfer
, b.pickup_date
, b.pickup_time
, b.return_time
, b.amount
, b.default_location
, b.start_address_route_comments
, b.start_address_route
, b.end_address_route_comments
, b.end_address_route
, u1.first_name
, u1.last_name
, b.transaction_Id
, b.manual_payment
, mr.AddressCount
, lu.origin
FROM bookingdetails b
LEFT JOIN log_users lu ON lu.uneaque_id = b.uneaque_id AND lu.command_type = 'NEW BOOKING'
LEFT JOIN (
SELECT booking_id
, COUNT(*) AS AddressCount
FROM booking_multiple_rides GROUP BY booking_id
) mr ON b.id = mr.booking_id
INNER JOIN userdetails u1 ON b.username = u1.email
AND u1.user_status IN ('Active', 'Blocked', 'Not_Active')
AND b.default_location = 1
and be sure you have proper index on
table bookingdetails a composite index on columns ( uneaque_id , id, default_location)
table log_users a composite index on columns (uneaque_id, command_type)
table userdetails a cmposite index on columns (email,user_status )
Tip 1.
Hiding a derived table in a LEFT JOIN is a prescription for sluggishness.
Replace
mr.AddressCount
with
( SELECT COUNT(*)
FROM booking_multiple_rides
WHERE booking_id = b.id
GROUP BY booking_id ) AS AddressCount
and get rid of the LEFT JOIN ( SELECT ... ) AS mr ON ..
Tip 2 Use explicit JOINs, no the old-fashioned "comma-join":
JOiN userdetails u1
ON b.username = u1.email
This won't help performance but it will make things clearer.
Tip 3: If you need an INNER JOIN (u1) after a LEFT JOIN, use parentheses. Else, put the inner joins first, then the left joins. This makes it easier to use, but may screw up the logic.
Tip 4: Don't use LEFT unless you need it. When you dont need it, it confuses the reader (and the Optimizer). (Again, no performance change.)
Tip 5: Why are you using DISTINCT? That takes an extra pass over all the resultset.
If those do not help enough, then provide SHOW CREATE TABLE so we can critique the indexes.
I have this query, but it takes about 15 seconds to finish.. how can i simplyfy it to get same result in less time? my problem is that i need all of this data at ones.
SELECT * FROM (
SELECT c.client_id, c.client_name, c.client_bpm,
c.client_su_name, c.client_maxbpm, s.bpm,
s.timestamp, m.mesure_id, ms.currentT
FROM tbl_clients c, tbl_meting m, tbl_sensor_meting s,
tbl_magsens_meting ms
WHERE c.client_id = m.client_id
AND (m.mesure_id = s.id_mesure
OR m.mesure_id = ms.id_mesure)
AND m.live =1
ORDER BY s.timestamp DESC
) AS mesure
GROUP BY mesure.client_id
I think the problem may be the OR condition from your WHERE clause? You seem to be trying to join to one table or another, which you can't do. So I've replaced it with a LEFT JOIN, so in the event no related records exist nothing will be returned.
I also took out your GROUP BY, as I don't think it was required.
SELECT c.client_id, c.client_name, c.client_bpm,
c.client_su_name, c.client_maxbpm, s.bpm,
s.timestamp, m.mesure_id, ms.currentT
FROM tbl_clients c
JOIN tbl_meting m ON m.client_id = c.client_id
LEFT JOIN tbl_sensor_meting s ON s.id_mesure = m.mesure_id
LEFT JOIN tbl_magsens_meting ms ON ms.id_mesure = m.mesure_id
WHERE m.live = 1
ORDER BY s.timestamp DESC
I've been at this for a bit now. Basically, I'm needing to add a derived column to count the hits to a weblog entry in the database. The problem is, the hits are being totaled and shown on only on the first record. Any Ideas? I've emboldened the parts of the query I'm talking about. The query is below:
SELECT DISTINCT(t.entry_id),
exp_categories.rank,
**exp_hits.hits,**
t.entry_id,
t.weblog_id,
t.forum_topic_id,
t.author_id,
t.ip_address,
t.title,
t.url_title,
t.status,
t.dst_enabled,
t.view_count_one,
t.view_count_two,
t.view_count_three,
t.view_count_four,
t.allow_comments,
t.comment_expiration_date,
t.allow_trackbacks,
t.sticky,
t.entry_date,
t.year,
t.month,
t.day,
t.entry_date,
t.edit_date,
t.expiration_date,
t.recent_comment_date,
t.comment_total,
t.trackback_total,
t.sent_trackbacks,
t.recent_trackback_date,
t.site_id as entry_site_id,
w.blog_title,
w.blog_name,
w.search_results_url,
w.search_excerpt,
w.blog_url,
w.comment_url,
w.tb_return_url,
w.comment_moderate,
w.weblog_html_formatting,
w.weblog_allow_img_urls,
w.weblog_auto_link_urls,
w.enable_trackbacks,
w.trackback_use_url_title,
w.trackback_field,
w.trackback_use_captcha,
w.trackback_system_enabled,
m.username,
m.email,
m.url,
m.screen_name,
m.location,
m.occupation,
m.interests,
m.aol_im,
m.yahoo_im,
m.msn_im,
m.icq,
m.signature,
m.sig_img_filename,
m.sig_img_width,
m.sig_img_height,
m.avatar_filename,
m.avatar_width,
m.avatar_height,
m.photo_filename,
m.photo_width,
m.photo_height,
m.group_id,
m.member_id,
m.bday_d,
m.bday_m,
m.bday_y,
m.bio,
md.*,
wd.*
FROM exp_weblog_titles AS t
LEFT JOIN exp_weblogs AS w ON t.weblog_id = w.weblog_id
LEFT JOIN exp_weblog_data AS wd ON t.entry_id = wd.entry_id
LEFT JOIN exp_members AS m ON m.member_id = t.author_id
LEFT JOIN exp_member_data AS md ON md.member_id = m.member_id
LEFT JOIN exp_category_posts ON wd.entry_id = exp_category_posts.entry_id
**LEFT JOIN
(
SELECT COUNT(*) AS hits, exp_hits.entry_id FROM exp_hits ORDER BY exp_hits.entry_id
) exp_hits ON t.entry_id = exp_hits.entry_id**
LEFT JOIN
(
SELECT exp_categories.cat_id, cat_name as rank
FROM exp_categories
WHERE exp_categories.group_id = '9'
) exp_categories ON exp_categories.cat_id = exp_category_posts.cat_id
WHERE t.entry_id IN (2,3,4) ORDER BY exp_categories.rank DESC, **exp_hits.hits DESC**, entry_date desc
Try changeing the subselect to
SELECT COUNT(*) AS hits,
exp_hits.entry_id
FROM exp_hits
GROUP BY exp_hits.entry_id
Out of curiosity, is your hits functionality something that can't be accomplished with the view_count_one/two/three/four fields already present in the database and supported by ExpressionEngine template tags?