This question already has answers here:
ORA-00918: column ambiguously defined in SELECT *
(4 answers)
Closed 9 years ago.
There are two tables in my Oracle database.
First table is (customers)-
customer_id Customer_name Customer_age Customer_address salary
103 Giriraj Rathi 22 Kolkata 12000
100 Subir Adhikari 22 Bolpur 10000
101 Rakesh Chatterjee 21 Tarkeshwar 8000
102 Jayanta Patra 20 Tarkeshwar 9000
104 Abhi Karmakar 22 Burdwan 8000
105 Mainak Manna 21 Burdwan 9000
106 Subho Gupta 20 Kolkata 10000
107 Aritra Das 23 Kolkata 7000
108 Pradip Paul 22 Kolkata 5000
109 Sourav Banerjee 22 Bolpur 9000
Second table is (Orders):
Order_id Order_date customer_id amount
200 12-03-13 100 1100
201 09-05-13 101 1400
202 07-04-12 103 2500
204 29-05-13 104 2400
203 09-02-13 105 9000
205 18-06-13 106 2100
206 09-07-13 107 1600
207 18-05-13 108 2900
209 18-04-13 109 2400
Now I wanted to join both the tables. So I used the query:
select customer_id,
customer_name,
customer_address,
order_id,order_date,
amount
from customers,
orders
where customers.customer_id=orders.customer_id;
I Googled about the error and found this happens when there is ambiguity in the SQL code itself, but in this case I see nothing.
It is always a good idea to add the table name/alias to the column like this
select c.customer_id,
c.customer_name,
c.customer_address,
o.order_id,
o.order_date,
o.amount
from customers c
inner join orders o on c.customer_id = o.customer_id
If you don't then the DB don't know which column to take and both tables have a column named customer_id.
Related
I have two tables:
Employees:
employee_id field max_amount
3 a 3000
4 a 3000
1 a 1600
2 a 500
4 b 4000
2 b 4000
3 b 1700
ordered by employee, field, amount desc.
Amounts (pol, premia,field):
pol premia field **assign_to_employee**
11 900 a 3
44 1000 a 3
55 1400 a 4
77 500 a 3
88 1300 a 1
22 800 b 4
33 3900 b 2
66 1300 b 4
Assign Stats Table:
employee_id field max_amount true_amount remain
3 a 3000 2400 600
4 a 3000 1400 1600
1 a 1600 1300 300
2 a 500 0 500
4 b 4000 2100 1900
2 b 4000 3900 100
3 b 1700 0 1700
The output : assign_to_employee field (merged to amounts table).
Algoritem wise : The method is to assign pol's to employees until the premia needs to be added to the cumulative_sum is bigger then the max amount per employee listed in the employees table. You always start with the employess with most max amount until you cannot add any other pols to the employee.
I start with the employees with the grater max_amount per field.
I keep doing this until no pols remains to be assign.
Can you help me solve this?
Thank you.
My Input data is :
Id salary
101 1000
101 1000
102 2500
102 3000
105 5000
105 5000
105 5000
106 12
106 142
106 12
Output :
102 2500
102 3000
106 12
106 142
106 12
I mean based on the id , I want to find out which Id has different salary. If the salary is the same in all the records , I want to discard those records. Kindly help.
select *
from t
where id in(
select Id
from t
group by Id
having max(salary) <> min(salary)
)
Id
salary
102
2500
102
3000
106
12
106
142
106
12
Fiddle
SELECT `Id`, `salary` FROM salary
WHERE Id IN( SELECT Id FROm salary GROUP By Id HAVING COUNT(DISTINCT SALARY) > 1)
Id
salary
102
2500
102
3000
106
12
106
142
106
12
fiddle
This question already has an answer here:
How can I perform this aggregate?
(1 answer)
Closed 9 years ago.
I have crated two table one is cutomer and other one is ord
select * from customers;
Customer table
1 101 jun 23 yyyy 15000
2 102 jas 24 zzzz 10000
3 103 fat 20 kkkk 20000
4 104 jini 40 llll 30000
5 105 michael 30 dddd 25000
6 106 das 25 hhhh 10000
7 107 vijay 26 mmmm 12000
8 108 thanku 31 jjjj 26000
9 109 vishnu 34 gggg 24000
10 110 vas 28 ffff 18000
select * from ord;
This is order table
1 12/11/2013 1:00:00 AM 102 2500
2 202 12/11/2013 4:14:17 AM 102 3000
3 203 12/9/2013 9:18:16 PM 103 2000
4 204 12/8/2013 12:00:00 PM 102 1000
5 205 12/24/2013 107 2000
This is tha union command that I have used
select c.name,c.salary,o.amount
from CUSTOMERS c
inner join ord o
on c.id=o.customer_id;
then the resulting table is
1 jas 10000 1000
2 jas 10000 3000
3 jas 10000 2500
4 fat 20000 2000
5 vijay 12000 2000
I want resulting table like this
1 jas 10000 6500
2 fat 20000 2000
3 vijay 12000 2000
plz help me for solving this.
group by c.name, c.salary with sum(salary) is what you want:
select c.name, c.salary, sum(o.amount )
from CUSTOMERS c
inner join ord o on c.id=o.customer_id
group by c.name, c.salary;
try this if it will work.
select c.name,c.salary,sum(o.amount)
from CUSTOMERS c
inner join ord o
on c.id=o.customer_id
group by 1,2;
Thanks.
select c.name,c.salary,SUM(o.amount )
from CUSTOMERS c
inner join ord o
on c.id=o.customer_id
GROUP BY c.name,c.salary
I think this will work
Use Left Join or RIGHT JOIN
select c.name,c.salary,o.amount
from CUSTOMERS c
left join ord o
on c.id=o.customer_id;
Table: Movie
mID title year director
101 Gone with the Wind 1939 Victor Fleming
102 Star Wars 1977 George Lucas
103 The Sound of Music 1965 Robert Wise
104 E.T. 1982 Steven Spielberg
105 Titanic 1997 James Cameron
106 Snow White 1937 <null>
107 Avatar 2009 James Cameron
108 Raiders of the Lost Ark 1981 Steven Spielberg
Table: Rating
rID mID stars ratingDate
201 101 2 2011-01-22
201 101 4 2011-01-27
202 106 4 <null>
203 103 2 2011-01-20
203 108 4 2011-01-12
203 108 2 2011-01-30
204 101 3 2011-01-09
205 103 3 2011-01-27
205 104 2 2011-01-22
205 108 4 <null>
206 107 3 2011-01-15
206 106 5 2011-01-19
207 107 5 2011-01-20
208 104 3 2011-01-02
I need to fetch movies which are not rate yet. In this case Titanic (mID 105) and Star Wars (mID 102) never get rate in rating table.
I figured out it with
select distinct movie.title from movie,rating where
rating.mid!=movie.mid except select distinct movie.title from
movie,rating where rating.mid=movie.mid
however I think it might have better (easier/cleaner) way to do.
Simple:
SELECT Movies.* FROM Movies LEFT JOIN Rating ON Movies.mID = Rating.mID WHERE Rating.mID IS NULL
If I understood your question properly, that looks like textbook application of outer joins.
You could do it like this:
SELECT * FROM Movie WHERE mid NOT IN (SELECT DISTINCT(mid) FROM Rating)
Basically it will select all records from the movie table that are not in the rating table, linking them on the 'mid' column, which I am assuming is a unique identifier.
I will add another possibility.
Select [list columns here]
from Movie m
where NOT exists (SELECT * FROM RATING r where m.mid = r.mid)
I am working on a query for a report in Oracle 10g.
I need to generate a short list of each course along with the number of times they were offered in the past year (including ones that weren't actually offered).
I created one query
SELECT coursenumber, count(datestart) AS Offered
FROM class
WHERE datestart BETWEEN (sysdate-365) AND sysdate
GROUP BY coursenumber;
Which produces
COURSENUMBER OFFERED
---- ----------
ST03 2
PD01 1
AY03 2
TB01 4
This query is all correct. However ideally I want it to list those along with COURSENUMBER HY and CS in the left column as well with 0 or null as the OFFERED value. I have a feeling this involves a join of sorts, but so far what I have tried doesn't produce the classes with nothing offered.
The table normally looks like
REFERENCE_NO DATESTART TIME TIME EID ROOMID COURSENUMBER
------------ --------- ---- ---- ---------- ---------- ----
256 03-MAR-11 0930 1100 2 2 PD01
257 03-MAY-11 0930 1100 12 7 PD01
258 18-MAY-11 1230 0100 12 7 PD01
259 24-OCT-11 1930 2015 6 2 CS01
260 17-JUN-11 1130 1300 6 4 CS01
261 25-MAY-11 1900 2000 13 6 HY01
262 25-MAY-11 1900 2000 13 6 HY01
263 04-APR-11 0930 1100 13 5 ST03
264 13-SEP-11 1930 2100 6 4 ST03
265 05-NOV-11 1930 2100 6 5 ST03
266 04-FEB-11 1430 1600 6 5 ST03
267 02-JAN-11 0630 0700 13 1 TB01
268 01-FEB-11 0630 0700 13 1 TB01
269 01-MAR-11 0630 0700 13 1 TB01
270 01-APR-11 0630 0700 13 1 TB01
271 01-MAY-11 0630 0700 13 1 TB01
272 14-MAR-11 0830 0915 4 3 AY03
273 19-APR-11 0930 1015 4 3 AY03
274 17-JUN-11 0830 0915 14 3 AY03
275 14-AUG-09 0930 1015 14 3 AY03
276 03-MAY-09 0830 0915 14 3 AY03
SELECT
coursenumber,
COUNT(CASE WHEN datestart BETWEEN (sysdate-365) AND sysdate THEN 1 END) AS Offered
FROM class
GROUP BY coursenumber;
So, as you can see, this particular problem doesn't need a join.
I think something like this should work for you, by just doing it as a subquery.
SELECT distinct c.coursenumber,
(SELECT COUNT(*)
FROM class
WHERE class.coursenumber = c.coursenumber
AND datestart BETWEEN (sysdate-365) AND sysdate
) AS Offered
FROM class c
I like jschoen's answer better for this particular case (when you want one and only one row and column out of the subquery for each row of the main query), but just to demonstrate another way to do it:
select t1.coursenumber, nvl(t2.cnt,0)
from class t1 left outer join (
select coursenumber, count(*) cnt
from class
where datestart between (sysdate-365) AND sysdate
group by coursenumber
) t2 on t1.coursenumber = t2.coursenumber