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We are currently building a complicated financial report where every cell in the table is link to a group of accounts. Currently we will look at the group of a accounts and we manually figure out the filter/wildcards that defines that group. We need the filters to only include the accounts in the list. I was wondering if there a program to do this for us or is there an algorithm we can implement this. Also, all account numbers will be the same length.
Example:
Group A
10004
10005
10006
21001
21023
Group B
10056
10055
Group C
10000
10001
10002
10003
10004
10005
10006
10007
10008
10009
Group A would look like 1000[4,5,6], 21001, 21023
Group B would look like 1005[5,6]
Group C would look like 1000%
One solution that comes to mind is trie.
The general algorithm would be to find the longest prefix starting from the 1-st level(not 0-th level), fix this prefix and then append the different suffixes. Hope you will guess the next steps.
For example
Group A would look like 1000[4,5,6], 21001, 21023
Trie would look like
In this case the result is: 1000[4,5,6], 210[01,23]
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I'm building an app that recommends people to other people based on how frequently they've been to the same place.
So for a given person A (the one you want to give a suggestion), I have a table of all others persons and the amount of time they've been to a place. i.e, I get this:
idPerson | idPlace | nbTimesPersonWent | nbTimesPersonAWent
10 | 1 | 3 | 10
11 | 2 | 1 | 22
12 | 1 | 11 | 10
13 | 3 | 8 | 2
What I'm struggling with is finding which of these idPerson is the "best" person to recommend to A.
Is there a way (preferably pure SQL), to sort this table from "closer" value of nbTimesPersonWent and nbTimesPersonWent to "less close" values?
I would recommend using the following tables
Person:
id
Place:
id
Visit:
person_id, place_id, time_spent
Now you must choose which way you will sort people that are interesting to a particular person a.
Many different sort functions exists. For any person of interest a, you can rank any other person b based on many different criteria. For example:
f(a,b) = Sum of min_time(a,b,p) for all places p that both a and b have visited, where min_time(a,b,p) = minimum of the time a and b have spent at place p
f(a,b) = The number of places that both a and b have visited
The difference between the two methods is that the first consider the time spent at different places and that the second only considers the number of places commonly visited. You can also define functions that limits the impact of having spent much time the same place, compared to distributing that time over multiple places.
If you can specify an exact ranking criteria, I will be happy to help you write a query for it.
UPDATE: Here is an example of sorting by the 2nd ranking criteria. That is, by the number of visited places in common: sqlfiddle.com/#!9/b56745/1/0
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Today i went for my first interview for .Net Developer.
Interviewer asked me one tricky question but I can't able to answer that.
I thought lots on that question but not get any solution on that question.
Question is...
ID | Name
1 | Ram
2 | Prathamesh
3 | Naresh
4 | Dasharath
Update this table with following condition;
If Name's character is less than 6 letters then New value must be like "Ram***"
(* mark will be added until characters length is 6)
and if it more than 6 letters all extra letters should be remove.
Result like this :
ID | Name
1 | Ram*** /* added three * marks */
2 | Pratha /* removed extra letters */
3 | Naresh /* No changes */
4 | Dashar /* removed extra letters */
SELECT LEFT(NAME+'******',6) FROM TABLE
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I working on these problems for a class I"m taking, but this one has me stumped. Here is the problem:
--Using the AUTHOR table, write a query that will list all information about authors
--whose first name ends with an “A”. Put the results in descending order of last name,
--and then ascending order by first name. This should be done using a single query.
Here is what I've come up with so far:
SELECT *
FROM author
WHERE(fname LIKE '%A')
ORDER BY lname DESC, fname ASC;
However all I get in the result is the information ordered by last name descending. First name ascending doesn't seem to work.
Any thoughts on what I'm missing? Using Oracle Express 10G, if it matters.
Thanks.
There is nothing wrong with your query. All you have to do is just pay attention to the data :-)
Here is how you would interpret your data output:
--------------+--------------
zzz | john
zza | adam
zaa | bob
ccc | jack
ccc | john
cca | mike
So, ordering works just you instruct Oracle - lname desc, fname acs, but you need to realize that fname asc comes in a picture once lname desc is processed. In other words: ZZZ comes before ZZA , but once CCC is ordered then and only then jack comes before john .
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I need to identify situations in a vacation booking database where an approver and submitter are the same person. Data looks like this:
TIME VACATION BOOKING ACTION NAME
1:00:00 1 SUBMIT Mike
1:01:00 1 APPROVE Mike
1:02:00 2 SUBMIT Jane
1:03:00 2 APPROVE Mike
Is "Count" the most efficient way to do this in SQL Queries?
I would want to "catch" the Mike results in Vacation Booking 1 above.
You could use count, but I would prefer a self-join
SELECT * FROM Bookings B1
INNER JOIN Bookings B2
ON B1.[Vacation Booking]= B2.[Vacation Booking]
AND B1.Action = 'SUBMIT'
AND B2.Action = 'APPROVE'
AND B1.Name = B2.Name
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we have the below table
COUNTRY TOP_COUNTRY
-------------------
ST. HELENA OTHERS
BARBADOS OTHERS
UNITED STATES UNITED STATES
**RUSSIA OTHERS**
NETHERLANDS OTHERS
**GERMANY OTHERS**
ANGUILLA OTHERS
AUSTRALIA AUSTRALIA
CHINA CHINA
I would like to update TOP_COUNTRY row value for a few countries with the names as shown in COUNTRY column.
For eg:
Right now, we RUSSIA shown as 'OTHERS' in TOP_COUNTRY but i would like to update it to the 'RUSSIA'.
This needs to be done for a couple of values..
Can you please let me know how we can get this done..
You can do:
UPDATE tableName
SET TOP_COUNTRY = COUNTRY
WHERE <YourCLause>
In if you want a list of COUNTRY to be updated you can do:
WHERE COUNTRY IN ("COUNTRY1","COUNTRY2",...);
update [YourTableName] set top_country = 'RUSSIA'
where COUNTRY='RUSSIA'