I have two tables:
tcars
id | name | car_price
----|---------------------|------------
1 |First_car_name | 1000
2 |Second_car_name | 1200
tcar_optionals
id | id_car | spec | opt_included |price
----|----------|------|-------------------------
1 | 2 |Spec1 | true | 500
2 | 2 |Spec2 | true | 100
3 | 2 |Spec3 | false | 500
4 | 2 |Spec4 | true | 0
5 | 1 |Spec5 | false | 500
6 | 1 |Spec6 | true | 0
And the following query:
select t1.id, coalesce(t1.car_price, 0)+ coalesce(sum(t2.price), 0) as total_price
from tcars t1
left join tcar_optionals t2 on t2.id_car = t1.id
where t2.opt_included and t2.price>0 and t1.id=?
group by t1.id, t1.car_price
It returns the id from tcars and the total_price(car_price+price of included optionals that have price>0).
Example:
for t1.id=2 returns:
id | total_price
----|------------
2 | 1800
The problem appears when I have no included optionals with price>0, for example t1.id = 1.
What it returns:
id | total_price
----|------------
What I need is return only t1.car_price as total_price if there are no included optionals with price>0:
id | total_price
----|------------
1 | 1000
Can someone help me with this problem, please?
You should firstly join the tables with all conditions on the second table and aggregate values from this (joined) result, e.g:
select id, coalesce(car_price, 0)+ coalesce(sum(price), 0) total_price
from tcars
left join tcar_optionals on id = id_car and spec_included
-- where id = 1
group by id, car_price
The condition q1.id_car=1 in the where clause effectively turns your outer join into an inner join because for rows not matching the join condition q1.id_car will be null and the comparison =1 will remove those rows again.
You would need to put that into the JOIN condition - but as you already have a condition on the id_car in the derived table ("q1"), you don't need it anyway.
The other possibility would be to filter on the corresponding value from the tcars table: where t1.id = 1
Edit
By moving the conditions on the t2 table to the join condition you do get what you want:
select t1.id, coalesce(t1.car_price, 0) + coalesce(sum(t2.price), 0) as total_price
from tcars t1
left join tcar_optionals t2
on t2.id_car = t1.id
and t2.opt_included and t2.price > 0 --<< conditions for tcar_optionals go here
where t1.id = 1 --<< limit the car you want to see
group by t1.id;
If id is defined as the primary key in tcars, then group by t1.id is enough.
See the example here: http://rextester.com/YOYF30261
select (t1.car_price + coalesce(extra_price, 0)) as start_price
from tcars t1
left join (select id_car,sum(price) as extra_price from tcar_optionals
where opt_included and price > 0 group by 1) q1 on q1.id_car = t1.id
where t1.id=$1
Related
I have two tables of data which I can join using a left join linked on the ID in both tables. Where the course and the person are the same, I need to populate the RegNumber as the same as the RegNumber which is already there for 1 row:
How it is currently: if I join table 1 and table 2 with a left join.
Table 1
ID | Course| Person
67705 | A | 1
68521 | A | 1
85742 | A | 1
89625 | A | 1
67857 | B | 2
86694 | B | 2
88075 | B | 2
88710 | C | 3
47924 | C | 3
66981 | C | 3
12311 | B | 1
12312 | B | 1
12313 | B | 1
Table 2
ID | RegNumber
67705 | N712316
NULL | NULL
NULL | NULL
NULL | NULL
67857 | N712338
NULL | NULL
NULL | NULL
NULL | NULL
47924 | M481035
NULL | NULL
12311 | N645525
NULL | NULL
NULL | NULL
I need table 2 to look like this:
ID | RegNumber
67705 | N712316
68521 | N712316
85742 | N712316
89625 | N712316
67857 | N712338
86694 | N712338
88075 | N712338
88710 | N712338
47924 | M481035
66981 | M481035
12311 | N645525
12312 | N645525
12313 | N645525
That is, I need to insert new rows into Table 2
Can anyone help me please? This is Totally beyond my capability!
insert into table2 (ID,RegNumber)
select t1.ID,reg.regNumber
from table1 t1
cross join (select top 1 regNumber from table2 r2 join table1 r1
on r1.Id = r2.Id
and r1.Course = t1.Course
and r1.Person = t1.person
order by id) reg
where not exists (select 1 from table2 t2 where t1.ID = t2.ID)
you can improve performance a little bit by loading data into temp table first :
select t1.ID , Course,Person,regNumber
into #LoadedData
from table1 t1
join table2 t2 on t1.Id = t2.ID
insert into table2 (ID,RegNumber)
select t1.ID,reg.regNumber
from table1 t1
cross join (select top 1 regNumber from #LoadedData l
where l.Course = t1.Course
and l.Person = t1.person
order by id) reg
where not exists (select 1 from #LoadedData l where t1.ID = l.ID)
in either case having an index on (ID, Course, Person) will help with performance
Assuming:
You are missing items in table 2 that inherit data from other records in table 1.
What makes two different IDs share the same Regnumber is to have BOTH course and person number in common.
You really need to join table 1 to itself to create the mapping that associates ID 67705 with ID 68521, then you can join in table 2 to pick up the Regnumber.
Try this:
Insert into table2 (ID,RegNumber)
Select right1.ID, left2.RegNumber
From (
(table2 left2 INNER JOIN
table1 left1 On (left1.ID=left2.ID)
INNER JOIN table1 right1 On (left1.Course=right1.Course AND left1.Person=right1.Person)
) LEFT OUTER JOIN table2 right2 On (right1.ID=right2.ID)
WHERE right2.ID Is Null
The 4th table join (alias right2) is purely defensive, to handle two records in table2 having identical Person & Course in table1.
I have solved this myself.
I concatenated the person and course columns and then joined them using that new concatenated field
insert into table 2 (ID,RegNumber)
select X1.ID,X2.Regnumber
from (select concat(course,person) as X,ID from table1) X1
join (select concat(t1.course,t1.person) as X, t2.RegNumber
from table1 t1
join table2 t2 on t1.ID = t2.ID) X2
on X1.X = X2.X
where X1.ID not in (select ID from table2)
I've got myself in a bit of a mess on something I'm doing where I'm trying to get two tables linked together based on multiple bits of info.
I want to link one table to another based on the basic rules of(in this hierarchy)
where main linking is where orderid matches between the two tables
records from table 2 where valid=Y,
from those i want the valid records which has the highest seqn1 number and then from those the one that has the highest seqn2 value
table1
orderid | date | otherinfo
223344 | 22/10/2020 | okokkokokooeodijjf
table2
orderid | seqn1 | seqn2 | valid | additonaldata
223344 | 1 | 3 | y | sdfsfsf
223344 | 2 | 1 | y | sffferfr
223344 | 2 | 2 | y | sfrfrefr -- This row
223344 | 2 | 3 | n | rfrg66rr
223344 | 2 | 4 | n | adwere
223344 | 3 | 4 | n | adwere
so would want the final record to be
orderid | date | otherinfo | seqn1 | seqn2 | valid | additonaldata
223344 | 22/10/2020 | okokkokokooeodijjf | 2 | 2 | y | sfrfrefr
I started off with the code below but I'm not sure I'm doing it right and I can't seem to get it to pay attention to the valid flag when i try to add it in.
SELECT * FROM table1
left JOIN table2
ON table1.orderid = table2.orderid
AND table2.seqn1 = (SELECT MAX(table2.seqn1) FROM table2 WHERE table1.orderid = table2.orderid)
AND table2.seqn2 = (SELECT MAX(table2.seqn2) FROM table2 WHERE table1.orderid = table2.orderid
AND table2.seqn1 = (SELECT MAX(table2.seqn1) FROM table2 WHERE table1.orderid = table2.orderid))
Could someone help me amend the code please.
Use row_number analytic function with partition by orderid and order by SEQNRs in the order you need. No need for multiple subselects. To add more selections for the single row, use CASE to map your values to numbers and order by them also.
Fiddle here.
with l as (
select *,
rank() over(partition by orderid order by seqn1 desc, seqn2 desc) as rn
from line
where valid = 'y'
)
select *
from header as h
join l
on h.orderid = l.orderid
and l.rn = 1
How about something like this:
;
with cte_table2 as
(
SELECT ordered
,MAX(seqn1) as seqn1
,MAX(seqn2) as seqn2
FROM table2
where valid = 'y'
group by ordered --check if you need to add 'valid' to the group by but I don't think so.
)
SELECT
t1.*
,t3.otherinfo
--,t3.[OtherFields]
from table1 t1
inner join cte_table2 t2 on t1.orderid = t2.orderid -- first match on id
left join table2 t3 on t3.orderid = t2.orderid and t3.seqn1 = t2.seqn1 and t3.seqn2 = t2.seqn2
I have two tables:
TABLE1
id_attr
-------
1
2
3
TABLE2
id | id_attr | val
----------------------
10 | 1 | A
10 | 2 | B
As a result I want a table that show:
RESULT
id | id_attr | val
----------------------
10 | 1 | A
10 | 2 | B
10 | 3 | NULL
So I want the row with id=10 and id_attr=3 also when id_Attr=3 is missing in TABLE2 (and I know that because I have a NULL value (or something else) in the val column of RESULT.
NB: I could have others ids in table2. For example, after insert this row on table2: {11,1,A}, as RESULT I want:
id | id_attr | val
----------------------
10 | 1 | A
10 | 2 | B
10 | 3 | NULL
11 | 1 | A
11 | 2 | NULL
11 | 3 | NULL
So, for every id, I want always the match with all id_attr.
Your specific example only has one id, so you can use the following:
select t2.id, t2.id_attr, t2.val
from table2 t2
union all
select 10, t1.id_attr, NULL
from table1 t1
where not exists (select 1 from table2 t2 where t2.id_attr = t1.id_attr);
EDIT:
You can get all combinations of attributes and ids in the following way. Use a cross join to create all the rows you want and then a left join to bring in the data you want:
select i.id, t1.id_attr, t2.val
from (select distinct id from table2) i cross join
table1 t1 left join
table2 t2
on t2.id = i.id and t2.id_attr = t1.id_attr;
It sounds like you want to do just an outer join on id_attr instead of id.
select * from table2 t2
left outer join table1 t1 on t2.id_attr = t1.id_attr;
I have a following table called Test:
Id | SomeId | Value
-----------------------------------------------------
019D9E52-41D1-45DF-81B6-C7CC484115A7 | 1 | 1
262640CA-65C2-4E30-8654-E187ACA1EEF4 | 1 | 1
53710AFC-4E19-4B1C-B68B-CDB713EC3D62 | 1 | 2
8FF7E77C-D04C-4961-82D9-87C2E5A1A096 | 1 | 2
-----------------------------------------------------
119D9E52-41D1-45DF-81B6-C7CC484115A7 | 2 | 1
762640CA-65C2-4E30-8654-E187ACA1EEF4 | 2 | 1
93710AFC-4E19-4B1C-B68B-CDB713EC3D62 | 2 | 2
4FF7E77C-D04C-4961-82D9-87C2E5A1A096 | 2 | 2
And there is a view called TestView:
SomeId | Value | Description
----------------------------
1 | 1 | 'One'
1 | 2 | 'Two'
1 | 3 | 'Three'
----------------------------
2 | 1 | 'One'
2 | 2 | 'Two'
These are just pseudo code examples.
I want to count all the values from the Test table (for a specific [SomeId]), and if value from the TestView (with a specific [SomeId]) is not in the Test table I just want to display 0 as count.
If I wanted to count values WHERE [Test].[SomeId] = 1, here's the expected result:
Value | Count
-----------------
One | 2
Two | 2
Three | 0
This is my query so far:
SELECT
tv.[Description] AS [Value],
COUNT(t.[Id]) - COUNT(tv.[Value]) AS [Count]
FROM [TestView] AS tv
LEFT JOIN [Test] AS t ON
t.[SomeId] = tv.[SomeId]
AND t.[Value] = tv.[Value]
WHERE
t.[SomeId] = 1
GROUP BY
tv.[Description]
But this gives me bad result... Anyways, here's the SQL Fiddle
EDIT:
This is just an addition to a Test table. What is Test table has one more foreign key Id, let's call it OtherId. Now when I use the query from the answer I won't get the result I wanted. Here's the modified query:
SELECT
t1.Description AS Value,
COUNT(t2.Value) AS Count
FROM TestView t1
LEFT JOIN test t2
ON t1.Value = t2.Value AND t1.SomeId = t2.SomeId
WHERE t1.SomeId = 1
AND t2.[OtherId] = *something* -- this is the addition
GROUP BY t1.Value, t1.Description
ORDER BY t1.Value;
Try this:
SELECT
t1.Description AS Value,
COUNT(t2.Value) AS Count
FROM TestView t1
LEFT JOIN test t2
ON t1.Value = t2.Value AND t1.SomeId = t2.SomeId
WHERE t1.SomeId = 1
GROUP BY t1.Value, t1.Description
ORDER BY t1.Value;
Demo
Below is your Solution
SELECT
tv.[Description] AS [Value],
COUNT(t.[Id]) AS [Count]
FROM [TestView] AS tv
LEFT OUTER JOIN [Test] AS t ON tv.SomeId = t.SomeId
AND t.Value = tv.value
AND t.[SomeId] = 1
GROUP BY
tv.[Description]
Let us suppose the following table (e.g. a result of several inner join statements):
id | column_1 | column_2
------------------------
1 | 1 |
2 | 2 | 2
3 | | 3
Which you could for example get from the following statement:
select a.id, t1.column_1, t2.column_2
from a
left join t1 on a.id = t1.id
left join t2 on a.id = t2.id
Now, if i'd like to sum up t1.column_1 and t2.column_2 as follows
select
a.id,
t1.column_1,
t2.column_2,
(t1.column_1 + t2.column_2) as cumulated
from a
left join t1 on a.id = t1.id
left join t2 on a.id = t2.id
The result will look as follows:
id | column_1 | column_2 | cumulated
------------------------------------
1 | 1 | NULL | NULL
2 | 2 | 2 | 4
3 | NULL | 3 | NULL
My question basically is: is there a way to typecast NULL into 0 in order to do some math?
I have tried CONVERT(t1.column_1, SIGNED) and CAST(t1.column_1 as SIGNED), but a NULL stays a NULL.
Use IFNULL(column, 0) to convert the column value to zero.
Alternatively, the COALESCE function will do the same thing: COALESCE(column, 0), except
COALESCE is ANSI-compliant, IFNULL is not
COALESCE takes an arbitrary number of columns/values and will return the first non-null value passed to it.