I have two tables and I need to find the person with the highest value.
TABLE1
NAME ID
--------------- ---------------
MIKE 101
MIKE 102
BETTY 103
BETTY 104
BETTY 105
TIM 106
TABLE2
ID VALUE
-------- --------------
101 12
102 10
103 20
104 20
105 10
106 5
I can write a select statement that will give a result of name and values:
SELECT name, value
FROM table1, table2
WHERE table1.id = table.id;
NAME VALUE
----- ----------
MIKE 12
MIKE 10
BETTY 20
BETTY 20
BETTY 10
TIM 5
Now I need to aggregate the values of the rows with equal names and I can not figure it out. Am I going about it the correct way?
Please try this :
select a.name,max(b.value) as value
from table1 a
inner join table2 b on a.id = b.id
group by a.name
Anyway, you tagged mysql and oracle in the question. Luckily, this sql works in both. But you have to remove one of these two tags, to make sure which dbms are you use.
Use this.. and since your column names are unique, you don't need any alias.
select name, max(value) as MaxValue
from table1
inner join table2 on table1.id = table2.id
group by name
Related
I know this question has been asked a couple of times and i've tried to use the solution for my problem. Unfortunately it did not get me the output i wanted. I need to update ID column in one table by joining it to another table where the joining column does not have exact value.
TableA TableB
EmpNo EmpName ID EmpNo EmpName ID TermDate
101 John Doe Null 250termed_101 John Doe 250 11-15-2018
102 Jane Doe Null 251termed_102 Jane Doe 251 02-25-2019
101 Bryan Adams Null 252termed_101 Bryan Adams 252 03-12-2020
Here's what i tried but was unable to get the required output because the below query is giving me duplicates:
select *
from TableA as A left join
TableB as B
on B.EmpNo like '%' + A.EmpNo + '%' and A.EmpNo is not null
Output Required:
EmpNo EmpName ID
101 John Doe 250
102 Jane Doe 251
101 Bryan Adams 252
I need to populate ID column from TableB into TableA by joining these 2 tables on EmpNo. For the first record, John Doe is terminated on 11-15-2018 and his employee number is assigned to Bryan Adams with unique ID. I need to populate the ID column from TableB into Table A for the corresponding employee who had that number at the time.
Thanks in advance
If your problem is truly that you're getting duplicates that you don't want, you can throw a DISTINCT in. But your problem is in the data: Bryan Adams and John Doe both have employee numbers of 101, so they look duplicated when you join to TableB.
This SQL Fiddle might help you: http://sqlfiddle.com/#!18/f30476/10
You seem on the right path, the update statement should look like the following, also notice how I am making the like comparison more accurate:
update A SET
ID = B.ID
from
TableA as A
left join TableB as B on
B.EmpNo like '%_' + A.EmpNo and
A.EmpNo is not null;
that will break when you have 101 and 1101 or 2101, so it's not a good match, so let's revisit:
update A SET
ID = B.ID
from
TableA as A
inner join TableB as B on
RIGHT(B.EmpNo, len(B.EmpNo) - charindex('_', B.EmpNo)) = A.EmpNo
A.EmpNo is not null and --you don't need this,
charindex('_', B.EmpNo) > 0;--needed, otherwise you get string errors
Let's say I've got the following database table
Name | Nickname | ID
----------------------
Joe Joey 14
Joe null 14
Now I want to do a select statement that merges these two columns to one while replacing the null values. The result should look like this:
Joe, Joey, 14
Which sql statement manages this (if it's even possible)?
Simplest solution:
SQL> select * from t69
2 /
NAME NICKNAME ID
---------- ---------- ----------
Joe Joey 14
Joe 14
Michael 15
Mick 15
Mickey 15
SQL> select max(name) as name
2 , max(nickname) as nickname
3 , id
4 from t69
5 group by id
6 /
NAME NICKNAME ID
---------- ---------- ----------
Joe Joey 14
Michael Mickey 15
SQL>
If you have 11gR2 you could use the new-fangled LISTAGG() function but otherwise it is simple enough to wrap the above statement in a SELECT which concatenates the NAME and NICKNAME columns.
AFAIK,
the question is not clear.so i am making some assumptions over here.
your output has the first and 3rd columns for both the rows as same.
Only the 2nd field is different.
so u can simply write a select quest
select one.name,two.nick_name,one.id from
(select name,id from your_tb group by name,id) one,
your_tb two
where two.nickname is not NULL
and two.name=one.name
and two.id=one.id;
may be we can tune this but i am not good in tuning sql squeries,but this is the way i suppose u need.
I really don't know how to ask this question of mine.
I'll illustrate it using two tables I needed to join.
TABLE_1
Name Date
John 01-01-2016
May 04-08-2015
Rose 10-25-2016
Mary 12-15-2015
Ruby 07-07-2017
TABLE_2
Signatory DateFrom DateTo
President 1 01-01-2015 12-31-2015
President 2 01-01-2016 12-31-2016
RESULT:
Name Date Signatory
John 01-01-2016 President 2
May 04-08-2015 President 1
Rose 10-25-2016 President 2
Mary 12-15-2015 President 1
Ruby 07-07-2017 NULL
All I need to check if the Date of Table_1 is within the DateFrom and DateTo of Table_2 to get the Signatory field.
How I can do that?
Thanks a lot! ^_^
Try this:
SELECT t1.*, t2.Signatory
FROM Table_1 AS t1
LEFT JOIN Table_2 AS t2
ON t1."Date" BETWEEN t2.DateFrom AND t2.DateTo
What you need is just a LEFT JOIN with BETWEEN in the ON clause in order to determine whether Date field of Table_1 falls within any [DateFrom, DateTo] interval of Table_2.
Demo here
I want to convert table1 into table2. As I need to find out all distinct records excluding mis_date fro the table and most important condition is if any changes happen between two similar distinct records than in that case I want both of them as two distinct records.
Example:
i/p
empId Empname Pancard MisDate
123 alex ads234 31/11/2012
123 alex ads234 31/12/2012
123 alex ads234 31/01/2013
123 alex dds124 29/02/2013
123 alex ads234 31/03/2013
123 alex ads234 31/04/2013
123 alex dds124 30/05/2013
Expected o/p
empId Empname Pancard MisDate
123 alex ads234 31/11/2012
123 alex dds124 29/02/2013
123 alex ads234 31/03/2013
123 alex dds124 30/05/2013
Assuming there's only one row for each MisDate (otherwise you'll have to find another way to specify ordering):
SELECT t1.empId, t1.Empname, t1.Pancard
FROM Table1 t1
LEFT OUTER JOIN Table1 t2
ON t2.MisDate = (SELECT MAX(MisDate) FROM Table1 t3 WHERE t3.MisDate < t1.MisDate)
WHERE t2.empId IS NULL
OR t2.empId <> t1.empId OR t2.Empname <> t1.Empname OR t2.Pancard <> t1.Pancard
SQL Fiddle example
This performs a self-join on the previous record, as ordered by MisDate, outputting if it is different or if there is no previous record (it is the first row).
Note: You've got some funky dates. I assume these are just transcription errors and have corrected them in the fiddle.
Let's say I've got the following database table
Name | Nickname | ID
----------------------
Joe Joey 14
Joe null 14
Now I want to do a select statement that merges these two columns to one while replacing the null values. The result should look like this:
Joe, Joey, 14
Which sql statement manages this (if it's even possible)?
Simplest solution:
SQL> select * from t69
2 /
NAME NICKNAME ID
---------- ---------- ----------
Joe Joey 14
Joe 14
Michael 15
Mick 15
Mickey 15
SQL> select max(name) as name
2 , max(nickname) as nickname
3 , id
4 from t69
5 group by id
6 /
NAME NICKNAME ID
---------- ---------- ----------
Joe Joey 14
Michael Mickey 15
SQL>
If you have 11gR2 you could use the new-fangled LISTAGG() function but otherwise it is simple enough to wrap the above statement in a SELECT which concatenates the NAME and NICKNAME columns.
AFAIK,
the question is not clear.so i am making some assumptions over here.
your output has the first and 3rd columns for both the rows as same.
Only the 2nd field is different.
so u can simply write a select quest
select one.name,two.nick_name,one.id from
(select name,id from your_tb group by name,id) one,
your_tb two
where two.nickname is not NULL
and two.name=one.name
and two.id=one.id;
may be we can tune this but i am not good in tuning sql squeries,but this is the way i suppose u need.