I am encountering a problem I cannot bypass by myself and I that's why I am posting this question. There are a lot of other posts out there that give me half of the answer and I don't really know how to get it done.
I have 3 tables that contain informations about an ad. One table is "ad_names", another is "ad_locations" and the last one is "ad_details".
Ad_Names has : ad_title, ad_description, ad_date_added
Ad_Locations has : ad_country, ad_region, ad_city
Ad_Details has : ad_price, ad_author, ad_active
Basically I want apply location and details filters for an ad with a certain title.
For example, I want to search "food" keyword in ad-titles and then apply filters like "only from Kansas" or "Only from Kansas + price higher than 500USD". How do I do it?
first you will need to join the tables. do you know if you have a foreign key on the tables? like is there an Ad_ID field on all 3 tables? if the tables are large you may also want to index the fields you are searching. once you have all the data you will "filter" it with a where clause.
http://www.w3schools.com/sql/sql_where.asp
select * from ad_names as A
join ad_location as L on A.key=L.key
join ad_details as D on A.key=D.key
where A.ad_title like '%food%' and L.ad_region = 'Kansas' and D.ad_prics > 500;
depending on how your database is setup, you may get a cartesian result there, so you would have to look at your join. maybe a left outer join limiting the join in an on statement instead of in the where. it is hard to say without more information.
Join types
Assuming that Ad is a table with primary key id, which is a foreign key in each of the other tables (ad_id) then something along the lines of:
Location:
SELECT *
FROM Ad A
INNER JOIN Ad_Names N ON N.ad_id = A.id
INNER JOIN Ad_Locations L ON L.ad_id = A.id
INNER JOIN Ad_Details D ON D.ad_id = A.id
WHERE N.ad_title LIKE '%food%' AND L.ad_city = 'Kansas'
Price and location:
SELECT *
FROM Ad A
INNER JOIN Ad_Names N ON N.ad_id = A.id
INNER JOIN Ad_Locations L ON L.ad_id = A.id
INNER JOIN Ad_Details D ON D.ad_id = A.id
WHERE N.ad_title LIKE '%food%' AND L.ad_city = 'Kansas' AND D.ad_price > 500
Related
I have a little problem with INNER JOIN in mysql query. I have two tables the first is 'kontrola' and 2nd is 'naruszenia' In 'kontrola' table I have rows:
id
podmiot
miasto
wszczeto
zakonczono
naruszenie_id (Foreign KEY on 'naruszenia' table)
In my naruszenia table I have:
id
naruszenia
Now I want to display using INNER JOIN the naruszenie from 'naruszenia' table.
I've create somethin linke this:
$listakontroli = $connecting->query("SELECT * FROM kontrola INNER JOIN naruszenia ON
kontrola.naruszenie_id=naruszenia.id");
But the result is that when I want to display records in table I have changed the ID of first table(kontrola) and the naruszenia_id still showing id from naruszenia table. How to change it to display properly the word not id.
You could use explicit column name and refer to both the table (in this case using k an n) eg:
$listakontroli = $connecting->query("SELECT k.id
, k.podmiot
, k.miasto
, k.wszczeto7
, k.zakonczono
, n.naruszenia
FROM kontrola k
INNER JOIN naruszenia n ON k.naruszenie_id=n.id");
You need to use LEFT OUTER JOIN or separate the ID from the two tables. e.g.
$listakontroli = $connecting->query("SELECT kontrola.id as kid, naruszenia.id as nid, podmiot, miasto, etc* FROM kontrola INNER JOIN naruszenia ON kontrola.naruszenie_id=naruszenia.id");
This way you can properly distinguish the displayed IDs
I have one issue. I need to retrieve data from database as per some condition but some cases it fails. I am explaining my query below.
select b.member_id as b_member_id,
b.rest_name,
b.city,
b.proviance,
b.postal,
b.address,
b.country,
b.person,
b.mobile,
b.url,
b.status,
b.premium,
b.image,
b.business_phone_no,
b.email,
b.multiple_image,
b.latitude,
b.longitude,
b.quadrant,
d.member_id as d_member_id,
d.day_id,
d.cat_id,
d.subcat_id,
d.comment,
d.city,
d.special_images,
c.cat_id,
c.special,
sub.subcat_id,
sub.subcat_name,
sub.status,
sl.day_id,
sl.member_id,
sl.date_from,
sl.date_to
from db_restaurant_basic as b left join db_restaurant_detail as d on b.member_id=d.member_id
left join db_category as c on d.cat_id=c.cat_id
left join db_subcategory as sub on d.subcat_id=sub.subcat_id
left join db_special_images as sl on d.day_id=sl.day_id
where b.city='2' and d.day_id='4' and c.special='1'
and (((sl.date_from IS NULL or sl.date_from='') and (sl.date_to IS NULL or sl.date_to='')) or( sl.date_from <='2016-10-27' and sl.date_to >= '2016-10-27' ))
and b.status=1
and sub.status=1 group by d.subcat_id ORDER BY b_member_id DESC
Here my problem is some value also is coming which does not match the condition. Here b.city='2' but some value is coming which city=0 only also. Here i need the value should come as per proper matching. Please help me.
You are selecting d.city - from the db_restaurant_basic table - but the condition you set is b.city='2' - on the db_restaurant_detail table.
So any results with a city of 0, will show the city from the d / db_restaurant_detail table.
If you need to filter on that as well, you need to add and d.city=2.
You should probably check if you can normalize your database structure more to avoid having the same data in different tables.
Using the answer window's formatting options...
WHERE b.city = 2
AND d.day_id = 4 -- NOTE THAT THIS IS AN INNER JOIN!
AND c.special = 1 -- AND SO IS THIS !!
Since you have city twice in the selection list (b.city and d.city) I have to assume the city='0' value you mention is really d.city='0'. To make sure that also d.city is '2' you can add an additional condition in the where clause or you specify the join like this
select ... from db_restaurant_basic as b left join db_restaurant_detail as d on d.member_id=d.member_id and b.city = d.city left join ...
or even like this, getting rid of the ambiguity
select ... from db_restaurant_basic as b left join db_restaurant_detail as d using(member_id, city) left join ...
i have a problem with making a complicated query easier without the need to build the query with PHP.
My problem:
A product can have several properties eg. a color, a size and a state.
To get a product which has all 3 properties i can:
products p
INNER JOIN product_propeties p1 on p.pid = p1.pid AND p1.property = 1 (color)
INNER JOIN product_propeties p2 on p.pid = p2.pid AND p2.property = 2 (size)
INNER JOIN product_propeties p3 on p.pid = p3.pid AND p3.property = 3 (state)
This works fine. I will get all products which have all this 3 properties.
My problem is now that i dont want to generate p1,p2,p3 with PHP. The properties are listed in a table "property_groups". In this table i can group properties.
proberty|title|group_name
1|color|winterspecial
2|size|winterspecial
3|state|winterspecial
I want to join the "property_groups" table with "winterspecial" and my example from above i dont know how. Problem is that each property needs to exists. Several single joins do the job. But how to do it in a single MySQL Query.
With PHP i select all "winterspecial" and then i build the query with p1,p2...
There must be a better way. Beware that the properties must be AND connectet.
OR is easy this would be a simple subselect.
INNER JOIN product_propeties p1 on p.pid = p1.pid AND product_propeties IN (
SELECT * FROM property_groups WHERE "winterspecial"
)
This may look a bit clumsy, but is the only thing I can come up with at the moment...
In order to know whether a product has all winterspecial properties, we could count all existing winterspecial properties and the product's winterspecial properties and then compare the two numbers.
Then we can select from products and product_properties where the product ID is in the found set:
select ...
from products p
join product_properties pp on pp.pid = p.pid and pp.property in
(select property from property_groups where group_name = 'winterspecial')
where p.pid in
(
select pid
from product_properties
where property in
(select property from property_groups where group_name = 'winterspecial')
group by pid
having count(*) =
(select count(*) from property_groups where group_name = 'winterspecial')
);
Ahhh, I think I get the problem now. You seem to want all products that have the properties in the property_groups table, for a given group.
Here is an approach. Do a cross join to generate the list of products and properties. Then do a left join to match to product_properties. With an aggregation, you can easily tell if all the desired properties match an existing property:
select p.*
from products p cross join
property_groups g left join
product_properties pp
on pp.pid = p.id and pp.property = g.property
where g.group_name = 'winterspecial'
group by p.id
having count(distinct pp.property) = count(distinct g.property)
You can actually simply the having clause to one of these:
having sum(pp.property is null) = 0 -- no null values
having count(pp.property) = count(g.property) -- all match
These should all be equivalent.
I'm really struggling to get my head around this. I am trying to run a SELECT query from multiple tables.
This is what I have so far that doesn't work;
SELECT jira_issues.*, session_set.* FROM jira_issues, session_set
INNER JOIN reports on jira_issues.report_id = reports.id
WHERE jira_issues.report_id = 648
I have other tables (session_set, report_device) which has a ReportID and report_id column respectively.
I have a report table which has a Primary Key id. In the other tables the report.id key is linked with foreign keys.
Ultimately what I am trying to achieve is this:
I have an entry in the reports table with an id of 648. In the other tables (jira_issues, report_device, session_set), I also have entries which has a foreign key linked to the report id in the report table.
I want to run one SELECT Query to query the tables (jira_issues, report_device and session_set) and get all the data from them based on the report.id.
Thanks!
What about this:
SELECT * FROM jira_issues ji
LEFT JOIN session_set ss ON ji.report_id = ss.ReportID
LEFT JOIN report_device rd ON rd.report_id = ji.report_id
WHERE ji.report_id = 648;
Just say "no" to commas in the from clause. Always use explicit join syntax:
SELECT ji.*, session_set.*
FROM jira_issues ji inner join
reports r
on ji.report_id = r.id inner join
session_set ss
on ss.ReportId = r.report_id
WHERE ji.report_id = 648;
If some of the tables might have no corresponding rows, you might want left outer join instead of inner join.
Kindly try this out. You may get syntax error.
SELECT a., b. FROM jira_issues a, session_set b, reports c
Where a.report_id = c.id and b.report_id = c.id AND a.report_id = 648
I have a MYSQL query who have to list all post i want it to post. But it dont do it. It shows posts when i have more then one post in the table "meaOrder" with the same "ordCode". But when i have only on post in meaOrder, i don't show it. What can i do?
SELECT koden, wish, rnamn, bild, pris, cname, onsktext
FROM (
SELECT m.wishText as onsktext, m.meaOID as midn, m.ordcode as koden, w.wish as wish, r.meaName as rnamn, r.meaImg as bild,
r.meaPrice as pris, k.catName as cname from cats k, meals r, wishes w,
meaOrder m
join orders c on c.ordNR=4401
WHERE c.ordStatus=1 AND m.ordNR=c.ordNR AND m.meaID=r.meaID AND m.wishesID=w.id
AND r.catID=k.catID
) T
GROUP BY koden, rnamn, bild, pris, cname
ORDER BY midn DESC
TABLE orders
http://grab.by/m74E
TABLE meaOrder http://grab.by/m74Q
Try replacing the JOIN with RIGHT JOIN in this case. The difference is explained at JOIN Syntax page in MySQL docs . In short - JOIN returns row only if there are corresponding rows in both joined tables (inner join). LEFT JOIN / RIGHT JOIN return all rows from one of the tables and corresponding row if it exists from the other table (those are outer joins)
Do you need a subselect?
This seems to cover it:-
SELECT m.ordcode AS koden, w.wish AS wish, r.meaName AS rnamn, r.meaImg AS bild, r.meaPrice AS pris, k.catName AS cname, m.wishText AS onsktext
FROM cats k
INNER JOIN meals r ON r.catID = k.catID
INNER JOIN meaOrder m ON m.meaID = r.meaID
INNER JOIN wishes w ON m.wishesID = w.id
INNER JOIN orders c ON m.ordNR = c.ordNR
WHERE c.ordStatus = 1
AND c.ordNR = 4401
GROUP BY m.ordcode, r.meaName, r.meaImg, r.meaPrice, k.catName
ORDER BY midn DESC