MySQL Select ALL from Left Join - mysql

This query does not work. I want all the results from a LEFT JOIN where something is something. This is my exact code:
SELECT * FROM `swarovski_zones` WHERE `siteid`='200'
LEFT JOIN `trafficviews` ON `swarovski`.`id`=`trafficviews`.`adid`
swarovski_zones table is siteid 200
trafficviews table is adid 200
The 200 is the linking variable between the tables. I want everything from both tables where the ID is 200.

The query doesn't work because the syntax is incorrect. It should be:
select
from
join
on
where
group by
having
order by
limit
Giving you:
select *
from `swarovski_zones`
left join `trafficviews`
on `swarovski`.`id` = `trafficviews`.`adid`
where `siteid` = '200'
Also is siteid meant to be a string and not an integer?
I'm probably going to regret providing the list above...
Limit! I forgot Limit; the full syntax list is here

The problem here is that elements in your right table (trafficviews) might not have a correspondant row in your left table (swarovski_zones). So the left join will get all elements from the left and might leave out some elements from the right.
To solve this, you need an outer join. Your problem is that MySQL does not support outer joins :) This is solved in the following general way:
SELECT * FROM a LEFT JOIN b ON a.id = b.id
UNION ALL
SELECT * FROM a RIGHT JOIN b ON a.id = b.id WHERE a.id IS NULL;
Applied to your question this should be something like:
SELECT * FROM swarovski_zones s
LEFT JOIN trafficviews ON s.id = t.adid
UNION ALL
SELECT * FROM swarovski_zones s
RIGHT JOIN trafficviews ON s.id = t.adid WHERE s.id IS NULL
WHERE s.siteid = 200 or t.adid = 200
Give it a try.

User full outer join
SELECT * FROM `swarovski_zones` WHERE `siteid`='200'
FULL OUTER JOIN `trafficviews` ON `swarovski`.`id`=`trafficviews`.`adid`

Related

How to make LEFT OUTER JOIN except some colums?

I have 3 tables:
First "placement"
Second "user_info"
Third "user_placements"
I want to get all placement data with user infos,
How to do it?
I tried this, but result it not what I expected:
SELECT *, user_placements.id AS user_placements_id, placement.id AS placement_id
FROM placement
LEFT OUTER JOIN user_placements ON placement.id = user_placements.id_placement
you need to one more join with user info
SELECT placement.*,user_info.id as user_info_id,user_info.name as user_name,user_info.mobile as user_mobile
FROM placement LEFT OUTER JOIN user_placements ON placement.id = user_placements.id_placement
LEFT OUTER JOIN user_info ON user_info.id = user_placements.id_user
You are missing the second join:
SELECT *
FROM placement AS p
JOIN user_placements AS up ON p.id = up.id_placement
JOIN user_info AS u ON up.id_user = u.id
Replace the wildcard with the data you want.
You will of course get duplicated data with this query.

hide duplicate row sql phpmyadmin

i have problem about duplicate row.
And my purpose like this:
Can you help me sir what the query to do like that?
The code I have been using is as follows:
select a.id_task1, b.id_task, b.task, b.cycle_sequence_number, c.cycle_sequence_number FROM task_table a LEFT OUTER JOIN billing_cycle b ON (a.id_task1=b.id_task) LEFT OUTER JOIN header c ON (b.cycle_sequence_number = c.cycle_sequence_number) where a.id_task1< 23 order by b.cycle_sequence_number DESC;
Regards,
-Tri-
Sorry sir, i forgot post my code:
select a.id_task1, b.id_task, b.task, b.cycle_sequence_number, c.cycle_sequence_number
FROM task_table a
LEFT OUTER JOIN billing_cycle b ON (a.id_task1=b.id_task)
LEFT OUTER JOIN header c ON (b.cycle_sequence_number = c.cycle_sequence_number)
where a.id_task1< 23
order by b.cycle_sequence_number DESC;
In relational databases the results of your queries are relations/tables ('relation' and 'table' are synonymous expressions). So, let's name your query and use group bys:
select id_task1, id_task, task, max(b.cycle_sequence_number) as b_cycle_sequence_number, max(c.cycle_sequence_number) as c_cycle_sequence_number
from (...) t
group by id_task1, id_task, task
order by b_cycle_sequence_number
You should interpret b.cycle_sequence_number as b_cycle_sequence_number and c.cycle_sequence_number as c_cycle_sequence_number to avoid duplicate column names. I'm sorry for not rewriting your actual code, but I refuse to type in your code from a picture.
Edit: The real code is:
select a.id_task1, b.id_task, b.task, b.cycle_sequence_number, c.cycle_sequence_number FROM task_table a LEFT OUTER JOIN billing_cycle b ON (a.id_task1=b.id_task) LEFT OUTER JOIN header c ON (b.cycle_sequence_number = c.cycle_sequence_number) where a.id_task1< 23 order by b.cycle_sequence_number DESC;
Suggestion:
SELECT id_task1, id_task, task, max(b.cycle_sequence_number) as b_cycle_sequence_number, max(c.cycle_sequence_number) as c_cycle_sequence_number
FROM (SELECT a.id_task1, b.id_task, b.task, b.cycle_sequence_number as b_cycle_sequence_number, c.cycle_sequence_number as c_cycle_sequence_number
FROM task_table a
LEFT OUTER JOIN billing_cycle b
ON (a.id_task1=b.id_task)
LEFT OUTER JOIN header c
ON (b.cycle_sequence_number = c.cycle_sequence_number) where a.id_task1< 23) t
GROUP BY id_task1, id_task, task
ORDER BY b_cycle_sequence_number

Getting data differences between two queries

I have two queries that result two result sets i need to compare both the result sets and need to display the differences between them.Hope i will get good support.Thank you.These are my queries
Query:1
SELECT distinct c.sid_ident,c.fix_ident from corept.std_sid_leg as c INNER JOIN (SELECT sid_ident, transition_ident, max(sequence_num) seq, route_type FROM corept.std_sid_leg WHERE data_supplier='J' AND airport_ident='KBOS' GROUP BY sid_ident,transition_ident) b ON c.sequence_num=b.seq and c.sid_ident = b.sid_ident and c.transition_ident =b.transition_ident WHERE c.data_supplier='J' and c.airport_ident='KBOS';
Query:2
SELECT name,trans FROM skyplan_deploy.deploy_sids ON d.name=c.sid_ident WHERE apt = 'KBOS' AND name != trans;
Comparison is to be done on fields sid_ident in corept.std_sid_leg and name in skplan_deplay.deploy_sids. As Mysql does not support full outer join,I thought of using left join and right join and combine both the results.But i stuck up with this.Please help.I am getting syntax error while using left and right join.Thank you.
The following query should simulate a FULL OUTER JOIN in MySQL.
SELECT *
FROM A
LEFT OUTER JOIN B
ON A.NAME = B.NAME
WHERE B.ID IS NULL
UNION ALL
SELECT *
FROM B
LEFT OUTER JOIN A
ON B.NAME = A.NAME
WHERE A.ID IS NULL;
Compare the results of the with an actual FULL OUTER JOIN in SQL Server and you'll see it works.

LEFT OUTER JOIN query not returning expected rows

My aim is to do exactly what a LEFT OUTER JOIN intends to do using the 4th venn diagram: SQL Diagrams:
My query isn't returning any values at all, where in fact, it should be returning all within the Consultant_Memberships minus the one that is stored within Consultant_Memberships_Lists.
Please see the SQL Fiddle for an easier understanding:
SELECT *
FROM consultant_memberships
LEFT OUTER JOIN consultant_memberships_list
ON consultant_memberships.`id` =
consultant_memberships_list.membership_id
WHERE consultant_memberships_list.consultant_id = $id
AND consultant_memberships_list.membership_id IS NULL
The query is using '5' as an ID for demonstration purposes to try and pick out the correct rows.
You current query is basically doing an INNER JOIN because of the consultant_id = 5 on the WHERE clause. I believe you actually want to use:
SELECT *
FROM consultant_memberships m
LEFT OUTER JOIN consultant_memberships_list l
ON m.`id` = l.membership_id
AND l.consultant_id = 5
WHERE l.membership_id IS NULL;
See SQL Fiddle with Demo
Use
SELECT *
FROM consultant_memberships
LEFT Outer JOIN consultant_memberships_list
ON consultant_memberships_list.membership_id = consultant_memberships.`id`
and consultant_memberships_list.consultant_id = 5
where consultant_memberships_list.membership_id IS NULL;
The Where clause used before in your query "consultant_memberships_list.consultant_id = 5 " was neglecting the left outer join.

Is it possible to convert this subquery into a join?

I want to replace the subquery with a join, if possible.
SELECT `fftenant_farmer`.`person_ptr_id`, `fftenant_surveyanswer`.`text_value`
FROM `fftenant_farmer`
INNER JOIN `fftenant_person`
ON (`fftenant_farmer`.`person_ptr_id` = `fftenant_person`.`id`)
LEFT OUTER JOIN `fftenant_surveyanswer`
ON fftenant_surveyanswer.surveyquestion_id = 1
AND fftenant_surveyanswer.`surveyresult_id` IN (SELECT y.`surveyresult_id` FROM `fftenant_farmer_surveyresults` y WHERE y.farmer_id = `fftenant_farmer`.`person_ptr_id`)
I tried:
SELECT `fftenant_farmer`.`person_ptr_id`, `fftenant_surveyanswer`.`text_value`#, T5.`text_value`
FROM `fftenant_farmer`
INNER JOIN `fftenant_person`
ON (`fftenant_farmer`.`person_ptr_id` = `fftenant_person`.`id`)
LEFT OUTER JOIN `fftenant_farmer_surveyresults`
ON (`fftenant_farmer`.`person_ptr_id` = `fftenant_farmer_surveyresults`.`farmer_id`)
LEFT OUTER JOIN `fftenant_surveyanswer`
ON (`fftenant_farmer_surveyresults`.`surveyresult_id` = `fftenant_surveyanswer`.`surveyresult_id`)
AND fftenant_surveyanswer.surveyquestion_id = 1
But that gave me one record per farmer per survey result for that farmer. I only want one record per farmer as returned by the first query.
A join may be faster on most RDBMs, but the real reason I asked this question is I just can't seem to formulate a join to replace the subquery and I want to know if it's even possible.
You could use DISTINCT or GROUP BY, as mvds and Brilliand suggest, but I think it's closer to the query's design intent if you change the last join to an inner-join, but elevating its precedence:
SELECT farmer.person_ptr_id, surveyanswer.text_value
FROM fftenant_farmer AS farmer
INNER
JOIN fftenant_person AS person
ON person.id = farmer.person_ptr_id
LEFT
OUTER
JOIN
( fftenant_farmer_surveyresults AS farmer_surveyresults
INNER
JOIN fftenant_surveyanswer AS surveyanswer
ON surveyanswer.surveyresult_id = farmer_surveyresults.surveyresult_id
AND surveyanswer.surveyquestion_id = 1
)
ON farmer_surveyresults.farmer_id = farmer.person_ptr_id
Broadly speaking, this will end up giving the same results as the DISTINCT or GROUP BY approach, but in a more principled, less ad hoc way, IMHO.
Use SELECT DISTINCT or GROUP BY to remove the duplicate entries.
Changing your attempt as little as possible:
SELECT DISTINCT `fftenant_farmer`.`person_ptr_id`, `fftenant_surveyanswer`.`text_value`#, T5.`text_value`
FROM `fftenant_farmer`
INNER JOIN `fftenant_person`
ON (`fftenant_farmer`.`person_ptr_id` = `fftenant_person`.`id`)
LEFT OUTER JOIN `fftenant_farmer_surveyresults`
ON (`fftenant_farmer`.`person_ptr_id` = `fftenant_farmer_surveyresults`.`farmer_id`)
LEFT OUTER JOIN `fftenant_surveyanswer`
ON (`fftenant_farmer_surveyresults`.`surveyresult_id` = `fftenant_surveyanswer`.`surveyresult_id`)
AND fftenant_surveyanswer.surveyquestion_id = 1
the real reason I asked this question is I just can't seem to formulate a join to replace the subquery and I want to know if it's even possible
Then consider a much simpler example to begin with e.g.
SELECT *
FROM T1
WHERE id IN (SELECT id FROM T2);
This is known as a semi join and if desired may be re-written using (among other possibilities) a JOIN with a SELECT clause to a) project only from the 'outer' table, and b) return only DISTINCT rows:
SELECT DISTINCT T1.*
FROM T1
JOIN T2 USING (id);