I'm having a struggle here trying to grab some data from 3 database tables..
The idea is that users can fill out their profile with several fields, and I'm storing every profile field, field values and the users selected value in separate tables.
The structure of the tables look like this:
Table 'profile_fields'
- id
- name
- sort
- status (enum '0', '1')
Table 'profile_field_values'
- id
- profile_field_id
- name
Table 'user_profile_fields'
- user_id
- profile_field_id
- profile_field_value_id
Would be really nice if you could tell me how to construct this query, and why you used the JOIN you did.
Also, how would this table layout scale when the userbase grows?
Thank you so much in advance!
Edit:
OK, I still can't figure out how to make it return all the fields from 'profile_fields' along with the users selected option from 'user_profile_fields'. If the user hasn't selected a value, it should just be null.
This is my (non-functional) query so far:
SELECT PF.id AS field_id, PF.name AS field_name, UPF.profile_field_value_id AS value_id, PF.type, PFV.name
FROM profile_fields PF
LEFT JOIN profile_fields_values PFV ON PFV.profile_field_id = PF.id
LEFT JOIN user_profile_fields UPF ON UPF.user_id=1 AND PF.id = UPF.profile_field_id
WHERE length(PF.name) > 0 and PF.status = '1'
ORDER BY PF.sort
This query seems to work, but it does not fetch the name of the value from 'profile_field_values':
SELECT PF.id AS field_id, PF.name AS field_name, UPF.profile_field_value_id AS value_id, PF.type
FROM profile_fields PF
LEFT JOIN user_profile_fields UPF ON UPF.user_id =1
AND PF.id = UPF.profile_field_id
WHERE LENGTH( PF.name ) >0
AND PF.status = '1'
ORDER BY PF.sort
I think you have some unnecessary complexity in there. Maybe you should try
Table 'profile_fields'
id
name
sort
status (enum '0', '1')
Table 'profile_field_values'
id
user_id
profile_field_id
value
why are there 3 tables?
Seems like simple JOINs should work:
SELECT pf.id, pf.name, pf.sort, pf.status,
pfv.id, pfv.profile_field_id, pfv.name,
upf.user_id, upf.profile_field_id, upf.profile_field_value_id
FROM profile_fields pf
INNER JOIN profile_field_values pfv
ON pf.id = pfv.profile_field_id
INNER JOIN user_profile_fields upf
ON upf.profile_field_value_id = pfv.id AND upf.profile_field_id = pf.id
A Visual Explanation of SQL Joins
This uses an INNER JOIN to select all matching records from each table -- review the post to tell the difference between an INNER and an OUTER join.
Related
I am trying to only show unique userIds (userIds are (0,1,2,3,4,5,6,7,8,9 etc...) for the query I am running. I tried using DISTINCT in my query, but it only shows me unique values of the rows that have 2 or more of the same userId.
Is there a way I can use php to only show the unique values. My weak points are arrays and it makes it more complicated because its using data from a MySQLi query.
Example right now I have with the query now (lets say its GROUP BY rentPaid DESC and the rent total is 800.00 for all users):
userID rentPaid rentMonth
2--------800.00------April
1--------500.00------April
3--------400.00------April
3--------400.00------April
1--------200.00------April
1--------100.00------April
Example desired output:
userID rentPaid rentMonth
2--------800.00------April
1--------500.00------April
3--------400.00------April
Can I do this with MYSQL because I tried DISTINCT and it wouldn't work, how about PHP?
Query:
SELECT
properties.*,
leases.*,
users.userId, users.primaryPhone,
CONCAT(users.userFirstName,' ',users.userLastName) AS user,
admins.adminName, payments.*
FROM
properties
LEFT JOIN leases ON properties.propertyId = leases.propertyId
LEFT JOIN assigned ON properties.propertyId = assigned.propertyId
LEFT JOIN admins ON assigned.adminId = admins.adminId
LEFT JOIN users ON properties.propertyId = users.propertyId
LEFT JOIN payments ON properties.propertyId = payments.propertyId
WHERE
payments.rentMonth = '$currentMonth' AND
payments.rentYear = '$currentYear'
Edit: Please excuse my formatting, this is my first post.
Edit: Added query....its long, but works lol. I only want unique userIds (no double or triple userIds etc...)
I suspect this is what you want:
SELECT userID, MAX(rentPaid) AS maxRentPaid, rentMonth
FROM yourTable
WHERE rentMonth = "April"
GROUP BY userID
ORDER BY maxRentPaid
I have 5 mysql tables as described below.
clinics table
id
name
d_location_subscription table
id
clinic_id
t_id //t_id will contain a foreign key of d_cities, d_states or d_countries table
type "country" "state" "city"
d_countries table
id
name
code
d_states table
id
d_country_id
name
code
d_city table
id
d_state_id
name
code
d_location_subscription table is used to record clinic's subscription for a location(it may be a city, state or country). I'm expecting to get all subscribed cities for a specific
clinic using d_location_subscription table.
For example, if clinic A is subscribed to Texas state, I should be able to get all city ids for clinic A.
I created following sql query, it looks ugly but generate a close result what i want to achieve.
select
`d`.`id` AS `clinic_id`,
if((`dct`.`id` is not null),`dct`.`id`,if((`dct1`.`id` is not null),`dct1`.`id`,`dct2`.`id`)) AS `d_city_id`
from ((((((((
`d_location_subscriptions` `dls`
join `clinics` `d`
on((`d`.`id` = `dls`.`clinic_id`)))
left join `d_countries` `dc`
on(((`dc`.`id` = `dls`.`t_id`) and (`dls`.`type` = 'country'))))
left join `d_states` `ds`
on((`ds`.`d_country_id` = `dc`.`id`)))
left join `d_cities` `dct2`
on((`dct2`.`d_state_id` = `ds`.`id`)))
left join `d_states` `ds1`
on(((`ds1`.`id` = `dls`.`t_id`) and (`dls`.`type` = 'state'))))
left join `d_cities` `dct`
on((`dct`.`d_state_id` = `ds1`.`id`)))
left join `d_cities` `dct1`
on(((`dct1`.`id` = `dls`.`t_id`) and (`dls`.`type` = 'city'))))
)
when there is record with type "country" in d_location_subscription table, I receive following result. total number of records returned are equal to the number of d_states table records.
How should I get rid of those Null values by changing above query?
And please advice me if this is the correct way to acheive similar functionality. Thanks in advance :)
The quickest, dirtiest way to achieve what you want is just to append this where condition to your query:
WHERE d_city_id is not null
but you might prefer to rework your query and decide where you really need LEFT joins and not INNER joins
the IF() computed column is in essence what STT LCU was trying to offer, but you can't use that directly in the where for some reason.
I've rewritten your query, but with different aliases to better follow the origination of the tables / relationships to get the data. In the end, I've added a where to test for ANY ONE of the "ID" values as NOT NULL. If they are ALL Null, the record should be excluded..
select
d.id AS clinic_id,
if(CityViaState.id is not null, CityViaState.id,
if( ByCity.id is not null, ByCity.id, CityViaCountry.id )) AS d_city_id
from
d_location_subscriptions dls
join clinics d
ON dls.clinic_id = d.id
left join d_countries ByCountry
ON dls.t_id = ByCountry.id
and dls.type = 'country'
left join d_states StateViaCountry
ON ByCountry.id = StateViaCountry.d_country_id
left join d_cities CityViaCountry
ON StateViaCountry.id = CityViaCountry.d_state_id
left join d_states ByState
ON dls.t_id = ByState.id
and dls.type = 'state'
left join d_cities CityViaState
ON ByState.id = CityViaState.d_state_id
left join d_cities ByCity
ON dls.t_id = ByCity.id
and dls.type = 'city'
where
CityViaState.id is not null
OR ByCity.id is not null
OR CityViaCountry.id is not null
I have two tables and joined them to one different table
1 table named 'rec_dept'
id_dept
id_divisi
nama_dept
2 table named 'rec_divisi'
id_divisi
nama_div
3 joined table named 'rec_divdep'
id_divdep
id_divisi
id_dept
How to get nama_dept where in the same id_divisi?
Maybe you're looking for this:
SELECT `nama_dept` FROM `rec_dept` WHERE `id_divisi` IN (SELECT `id_divisi` FROM `rec_divdep`);
Hope that helps
you can do a SELECT query with a LEFT JOIN function to get data
SELECT a.`nama_dept` FROM `rec_dept` a
LEFT JOIN `rec_divisi` b
ON a.`id_divisi` = b.`id_divisi`
ORDER BY a.`id_divisi` ASC
SELECT documentation
LEFT JOIN documentation
select a.id_dept, a.id_divisi, a.nama_dept, b.id_divisi, b.nama_div, c.id_divdep, c.id_divisi from rec_divdep as c left join rec_divisi as b on (c.id_divisi = b.id_divisi) left join rec_dept as a on (c.id_divisi = a.id_divisi)
what database do you use. I code mine as mysql, basically I condition the three tables that has same id_divisi. I did not test it but I am pretty sure of the logic based on what I understand.
I have an instrument list and teachers instrument list.
I would like to get a full instrument list with id and name.
Then check the teachers_instrument table for their instruments and if a specific teacher has the instrument add NULL or 1 value in a new column.
I can then take this to loop over some instrument checkboxes in Codeigniter, it just seems to make more sense to pull the data as I need it from the DB but am struggling to write the query.
teaching_instrument_list
- id
- instrument_name
teachers_instruments
- id
- teacher_id
- teacher_instrument_id
SELECT
a.instrument,
a.id
FROM
teaching_instrument_list a
LEFT JOIN
(
SELECT teachers_instruments.teacher_instrument_id
FROM teachers_instruments
WHERE teacher_id = 170
) b ON a.id = b.teacher_instrument_id
my query would look like this:
instrument name id value
--------------- -- -----
woodwinds 1 if the teacher has this instrument, set 1
brass 2 0
strings 3 1
One possible approach:
SELECT i.instrument_name, COUNT(ti.teacher_id) AS used_by
FROM teaching_instrument_list AS i
LEFT JOIN teachers_instruments AS ti
ON ti.teacher_instrument_id = i.id
GROUP BY ti.teacher_instrument_id
ORDER BY i.id;
Here's SQL Fiddle (tables' naming is a bit different).
Explanation: with LEFT JOIN on instrument_id we'll get as many teacher_id values for each instrument as teachers using it are - or just a single NULL value, if none uses it. The next step is to use GROUP BY and COUNT() to, well, group the result set by instruments and count their users (excluding NULL-valued rows).
If what you want is to show all the instruments and some flag showing whether or now a teacher uses it, you need another LEFT JOIN:
SELECT i.instrument_name, NOT ISNULL(teacher_id) AS in_use
FROM teaching_instrument_list AS i
LEFT JOIN teachers_instruments AS ti
ON ti.teacher_instrument_id = i.id
AND ti.teacher_id = :teacher_id;
Demo.
Well this can be achieved like this
SELECT
id,
instrument_name,
if(ti.teacher_instrument_id IS NULL,0,1) as `Value`
from teaching_instrument_list as til
LEFT JOIN teachers_instruments as ti
on ti.teacher_instrument_id = til.id
Add a column and check for teacher_instrument_id. If found set Value to 1 else 0.
I've been working on a project that until now has only needed to find 1 row from the joined table. But now I need to grab multiple rows..
So as it stand my sql works something like:
Select rows for each company for this particular project which alone would find company details (name, id, telephone.. blah).
Then I join a table that contains form data submitted for each company (multiple forms - so multiple records)
Until now i have been specifying one formid to look for in the join, but now i need to specify multiple ones.
If I use WHERE form_id = 1 OR form_id = 2 OR form_id = 3 ... I get a result of only the first form match that is found per company..
If I mix up the query so it looks for the forms 1st and returns multiple records for each company with different form data - that works in this sense..
But I am then looping through this array in a view and creating a table row per record (previously each row was a new company) but using the latter would cause multiple records to show for the same company.
Any way I can do this? I tried group by with the latter method but this results in only 1 record again.
SELECT DISTINCT p.project_company_has_user_id, p.project_company_has_user_project_id, p.project_company_has_user_user_id, c.company_id, c.company_hall_no, c.company_company_name, c.company_type, c.company_country, c.company_stand_number, c.company_image_file_1, p2.project_id, p2.project_name, u.user_id, u.user_username, o.orders_id, o2.order_detail_id, o2.order_detail_product_id, f2.form_question_has_answer_id, f2.form_question_has_answer_request, f2.form_question_has_answer_form_id, f2.form_question_has_answer_user_id
FROM project_company_has_user p
INNER JOIN company c ON p.project_company_has_user_company_id = c.company_id
INNER JOIN project p2 ON p.project_company_has_user_project_id = p2.project_id
INNER JOIN user u ON p.project_company_has_user_user_id = u.user_id
INNER JOIN form f ON p.project_company_has_user_project_id = f.form_project_id
LEFT JOIN orders o ON p.project_company_has_user_user_id = o.orders_user_id
LEFT JOIN order_detail o2 ON ((o2.order_detail_orders_id = o.orders_id AND (o2.order_detail_product_id = 65 OR o2.order_detail_product_id = 68 OR o2.order_detail_product_id = 64)))
LEFT JOIN form_question_has_answer f2 ON ((f2.form_question_has_answer_form_id = 297 AND f2.form_question_has_answer_user_id = p.project_company_has_user_user_id))
WHERE (f.form_template_name = "custom" AND p.project_company_has_user_garbage_collection = 0 AND p.project_company_has_user_project_id = 48) AND (LCASE(c.company_country) LIKE "%uk%" OR LCASE(c.company_country) LIKE "%uk%") ORDER BY company_company_name asc
you need another field in order_detail as o2 . this field is row_index(position),etc for positioning record
LEFT JOIN order_detail o2 ON (o2.row_index=1 AND (o2.order_detail_orders_id = o.orders_id AND (o2.order_detail_product_id = 65 OR o2.order_detail_product_id = 68 OR o2.order_detail_product_id = 64)))
Personally I would use an Outer Join for the table of which elements you need to list all matches. Should you them need to clean up that data you can build the logic into the Join Condition (as step 2). Depending on the volume of data you are handling and whether or not you need to reuse it later in the same proc, you may want to post that primary dataset into a temp table and use that as source (primary) for your later logic.
Hope that helps. If you need the code, let me know, but it is pretty straight forward.
Regards
Mac