I have a table that stores id, item, food type, image and price
I want to limit the result to one of each type sold in the store e.g. dog food, cat food, dvd in descending order
Example of what is held in mysql database
table: Nunca
id item type image price
=========================================================
1 Pedigree Pouches dog food img1 $4.99
2 Cesar Classic Selection dog food img2 $3.99
3 Meaty Strips Chicken dog food img3 $2.99
4 Jelly Fish Selection cat food img4 $1.99
5 Bananas fruit img5 $2.84
6 Celery vegetables img6 $5.99
7 Apple fruit img7 $0.95
8 Pineapple Juice Soft drink img8 $0.99
9 Oranges fruit img9 $1.99
10 Cabbage vegetables img10 $0.99
11 Suicide Squad dvd img11 $12.99
The final result should look like this from the query
id item type image price
==========================================================
11 Suicide Squad dvd img11 $12.99
10 Cabbage vegetables img10 $0.99
9 Oranges fruit img9 $1.99
8 Pineapple Juice Soft drink img8 $0.99
4 Jelly Fish Selection cat food img4 $1.99
3 Meaty Strips Chicken dog food img3 $2.99
I have tried various mysql queries, but to no avail
select * from t where
id in(select max(t.id) id from t group by t.type)
order by id desc
I guess there can be window or join alternatives but this one seemed fitting for this purpose.
A typical method uses a correlated subquery:
select n.*
from nunca n
where n.id = (select max(n2.id) from nunca n2 where n2.type = n.type);
This will choose the last row of each type.
Related
I have a table called beverages. It has the attributes name, id, and size.
How would I make a query that finds all the drinks with both size "maxi" and size "medium"
In other words. I have to find the beverages with the same name that have both sizes, as each tuple can only have one size.
So you have a table:
CREATE TABLE beverages
(id INT,
NAME VARCHAR(50),
size VARCHAR(50));
And a sample data like this:
id
name
size
1
orange
medium
1
orange
medium
1
orange
maxi
1
orange
maxi
2
soda
medium
3
cola
maxi
4
lemon tea
medium
5
soy milk
medium
5
soy milk
medium
5
soy milk
medium
5
soy milk
maxi
5
soy milk
maxi
6
coffee
maxi
7
chocolate
maxi
And you want to find any drinks that have both size so you do a query like:
SELECT id, name, GROUP_CONCAT(DISTINCT size), COUNT(DISTINCT size)
FROM beverages
GROUP BY id, name
Whereby this query returns:
id
name
group_concat(size)
count(*)
1
orange
medium,maxi
2
2
soda
medium
1
3
cola
maxi
1
4
lemon tea
medium
1
5
soy milk
medium,maxi
2
6
coffee
maxi
1
7
chocolate
maxi
1
Now you found drinks where their GROUP_CONCAT(DISTINCT size) return more than one result and COUNT(DISTINCT size) return two.
Demo fiddle
I'm trying to GROUP, SORT and COUNT in a single query one of my table named 'commodities'.
Here is a simplification of my MySql table :
family sub_family name detailed_name
Agro Grains Wheat Wheat per 1 mt
Agro Grains Corn Corn per 1 mt
Agro Grains Sugar Sugar per 1 mt
Agro Fruits Apple Apple red
Agro Fruits Apple Apple green
Agro Fruits Apple Apple yellow
Agro Fruits Lemon Lemon classic
Wood Tree Lemon Lemon in logs
Wood Tree Oak Oak in logs
Wood Tree Epicea Epicea in logs
Wood Packaging Kraftliner Krafliner 3mm
I would like to :
GROUP by name
SORT by family, sub_family and lastly name
COUNTthe numbers of rows for each family, sub_family and then name (IN THE SAME sub_family)
So far I managed to do everything but COUNT in the same sub_family.
Indeed, the following query :
SELECT
TableC.family,
TableC.NbrFamily,
TableB.sub_family,
TableB.NbrSubFamily,
TableA.name,
TableA.NbrName
FROM
(
SELECT
family,
sub_family,
name,
COUNT(DISTINCT commodities.id) AS NbrName
FROM commodities GROUP BY name
) TableA
INNER JOIN
(
SELECT
sub_family,
COUNT(DISTINCT commodities.id) AS NbrSubFamily
FROM commodities GROUP BY sub_family
) TableB
ON (TableA.sub_family = TableB.sub_family)
INNER JOIN
(
SELECT
family,
COUNT(DISTINCT commodities.id) AS NbrFamily
FROM commodities GROUP BY family
) TableC
ON (TableA.family = TableC.family)
GROUP BY TableA.name
ORDER BY TableA.family,TableA.sub_family,TableA.name
which results in the following :
family NbrFamily sub_family NbrSubFamily name NbrName
Agro 7 Grains 3 Wheat 1
Agro 7 Grains 3 Corn 1
Agro 7 Grains 3 Sugar 1
Agro 7 Fruits 4 Apple 3
Agro 7 Fruits 4 Lemon 2
Wood 4 Tree 3 Lemon 2
Wood 4 Tree 3 Oak 1
Wood 4 Tree 3 Epicea 1
Wood 4 Packaging 1 Kraftliner 1
You can see that NbrName counts Lemon 2 times but I would like it to count it only 1 time because one lemon is in Fruits sub_family and the other in Tree sub_family.
[UPDATE] : Here are my desired results :
family NbrFamily sub_family NbrSubFamily name NbrName
Agro 7 Grains 3 Wheat 1
Agro 7 Grains 3 Corn 1
Agro 7 Grains 3 Sugar 1
Agro 7 Fruits 4 Apple 3
Agro 7 Fruits 4 Lemon 1
Wood 4 Tree 3 Lemon 1
Wood 4 Tree 3 Oak 1
Wood 4 Tree 3 Epicea 1
Wood 4 Packaging 1 Kraftliner 1
Just my guess of what you are asking for http://sqlfiddle.com/#!9/e9206/16
because it brings desired result:
SELECT A.family, C.NbrFamily,A.sub_family,B.NbrSubFamily,A.name,COUNT(A.Name)
FROM commodities as A
LEFT JOIN (
SELECT family,sub_family,COUNT(Name) AS NbrSubFamily
FROM commodities
GROUP BY family,sub_family
) B
ON A.sub_family = B.sub_family
AND A.family = B.family
LEFT JOIN (
SELECT family,COUNT(Name) AS NbrFamily
FROM commodities
GROUP BY family
) C
ON A.family = C.family
GROUP BY A.family,A.sub_family,A.name
ORDER BY A.id
I have many users that can select their choice from rank 1-4.
The table look like this:
username rank1 rank2 rank3 rank4
Perter Apple Orange Grape Melon
Adam Orange Melon Apple Grape
James Melon Grape Orange Apple
How do I get a table like this in php mysql
username Apple Orange Grape Melon
Peter 1st-choice 2nd-choice 3rd-choice 4th-choice
Adam 3rd-choice 1st-choice 4th-choice 2nd-choice
Jame 4th-choice 3rd-choice 2nd-choice 1st-choice
just think I have a table like shown below
**id** **product**
2 chocolate
1 chocolate
2 pepsi
3 fanta
2 pepsi
4 chocolate
5 chips
3 pizza
1 coke
2 chips
6 burger
7 sprite
0 pepsi
and want to arrange the above table in the manner shown below using only mysql
**id** **product**
0 pepsi
1 chocolate, coke
2 chocolate,fanta,chips
3 fanta,pizza
4 chocolate
5 chips
6 burger
7 sprite
how do I do it?
select id, group_concat(distinct product) as products
from your_table
group by id
order by id
Consider the database (made up for example):
Table 'owner'
id name
1 john
2 andrew
3 peter
Table 'duck'
id name ownerID
1 duck1 1
2 duck2 1
3 duck3 1
4 duck4 2
5 duck5 2
6 duck6 3
7 duck7 3
8 duck8 1
9 duck9 3
10 duck10 3
11 duck11 1
12 duck12 2
Table 'food'
id name type duckID
1 beef meat 4
2 grass veg 8
3 lemon fruit 5
4 apple fruit 3
5 pizza snack 7
I wish to write some SQL that for each OWNER, COUNT the number of ducks which eat some kind of food. For example for owner John, there would be 2 ducks (ducks 3 and 8).
So far I am writing this code:
select owner.name, count(duck.ownerID)
from duck, food, owner
where duck.id == food.duckID
and duck.ownerID == owner.id;
I am getting the result:
Peter | 5
Any suggestions are appreciated.
This is done with an group by clause:
select owner.name, food.name, count(duck.id)
from duck, food, owner
where duck.id == food.duckID
and duck.ownerID == owner.id
group by owner.name, food.name;
This query gives you one row for each combination of owner name and food name with the number of the owner's ducks eating this food.