I've made extensive research about auto-increment before posting this but couldn't find similar case:
I have a query pulling data from a main table, grouping by player_id and ordering by points desc, therefore creating a ranking output. My aim is to make the same query, once it finishes aggregating and sorting data, create a new column 'Rank' and auto increment it so it shows 1,2,3 etc since everything is already grouped by player and ordered by points DESC.
Thanks guys.
Example of the source table :
player_id-----------points-----
---1-------------------5----------
---1-------------------10---------
---1-------------------5---------
---2-------------------20---------
---2-------------------5---------
Desired output according to this example:
Rank------player_id-------score-----
----1----------2-----------25 POINTS ---------
----2----------1-----------20 POINTS ---------
EDIT
Rownum does the job well, no need for an auto increment virtual column! see Mutnowski's accepted answer below please.
Try this
SELECT #rownum:=#rownum+1 AS ‘rank’, Player_ID, Points FROM (SELECT Player_ID, SUM(Points) AS 'Points' FROM tblScores GROUP BY Player_ID ORDER BY Points DESC) AS foo, (SELECT #rownum:=0) AS foo2
I think you need to run a query to get your results without the rank, then run another query on first that selects all and adds the rank
Applying SUM to the Points column should produce the results you want.
SELECT #rownum:=#rownum+1 AS ‘rank‘,player_id, SUM(points)
FROM scores
GROUP BY player_id
ORDER BY SUM(points) DESC;
Related
I want to swap 2nd and 3rd column of one table using CTE.
I'm working with below query, which keeps throwing an error,
no such column: cte.comm1
Table - [SalComm] column: ID, Sal, Comm
with CTE as
(
SELECT ID as id1, sal as sal1, comm as comm1 from SalComm
) UPDATE SalComm SET sal=cte.comm1, comm=cte.sal1 where ID= cte.id1*
Could you please suggest to me the right query?
This answer assumes you are using SQL Server, or some other database, which supports directly updating common table expressions. I don't see the point at all of the aliases inside your CTE. If you want to swap columns values, just use the direct columns names:
WITH cte AS (
SELECT ID, sal, comm
FROM SalComm
)
UPDATE cte
SET sal = comm, comm = sal;
-- no WHERE clause needed, if you really want to cover the entire table
That being said, you could just as easily do the above update on the original table. Updatable CTEs are more useful when they generate some complex derived results which you intend to use as part of a later update. That does not appear to be the case here.
I picked an entire table as a Data Source and picked my fields. The SQL of it returns as:
SELECT customer_id AS customer_id,
country AS country,
count(invoice_num) AS total_invoices
FROM sales
GROUP BY customer_id,
country
ORDER BY total_invoices DESC
LIMIT 10000;
I do not want this ORDER BY total_invoices DESC as it is ruining the entire result. What should I do?
I think it always orders by the first metric. If you have multiple metrics, you can re-order them to change which one is used in the Order By clause.
Under Customization, the bar chart also has a "Sort Bars" option to sort the x-axis by label, which might work for you depending on what kind of result you're looking for.
I have a customers table with ID's and some datetime columns. But those ID's have duplicates and i just want to Analyse distinct ID values.
I tried using groupby but this makes the process very slow.
Due to data sensitivity can't share it.
Any suggestions would be helpful.
I'd suggest using ROW_NUMBER() This lets you rank the rows by chosen columns and you can then pick out the first result.
Given you've shared no data or table and column names here's an example based on the Adventureworks database. The technique will be the same, you partition by whatever makes the group of rows you want to deduplicate unique (ProductKey below) and order in a way that makes the version you want to keep first (Children, birthdate and customerkey in my example).
USE AdventureWorksDW2017;
WITH CustomersOrdered AS
(
SELECT S.ProductKey, C.CustomerKey, C.TotalChildren, C.BirthDate
, ROW_NUMBER() OVER (
PARTITION BY S.ProductKey
ORDER BY C.TotalChildren DESC, C.BirthDate DESC, C.CustomerKey ASC
) AS CustomerSequence
FROM dbo.FactInternetSales AS S
INNER JOIN dbo.DimCustomer AS C
ON S.CustomerKey = C.CustomerKey
)
SELECT ProductKey, CustomerKey
FROM CustomersOrdered
WHERE CustomerSequence = 1
ORDER BY ProductKey, CustomerKey;
you can also just sort the columns with date column an than click on id column and delete duplicates...
I have a quick question about the following piece of code. Why can we use 'NA' = for the subquery ? I mean, the subquery might return a group of values, not a single one, right? Could anyone tell me the reason? Many thanks for your time and attention.
proc sql;
select lastname, first name
from sasuser.staffmaster
where 'NA' =
(select jobcategory
from sasuser.supervisors
where staffmaster.empid = supervisors.empid);
quit;
Thanks again.
Assuming EMPID is a unique ID for an employee (I hope it is?), and each employee has only one supervisor, that query should resolve to a single row every time. (A single row for each row returned from the outer query, of course, which is important. Think of it like a join - that's basically what that is, a slightly oddly phrased join, which often will be turned into an actual join by the SQL parser.)
In general, however, sure, it could resolve to multiple rows. SAS will let you do the query, and if it returns just one row it works; if it returns 2+ rows, it fails. As Quentin pointed out in comments, this is a correlated subquery.
I have two tables I would like to call, but I am not sure if it is possible to combine them into one query or I have to some how call 2 different queries.
Basically I have 2 tables:
1) item_table: name/id etc. + category ID
2) category_table: categoryID, categoryName, categoryParentID.
The parent categories are also inside the same table with their own name.
I would like to call on my details from item_table, as well as getting the name of the category, as well as the NAME of the parent category.
I know how to get the item_table data, plus the categoryName through an INNER JOIN. But can I use the same query to get the categoryParent's name?
If not, what would be the mist efficient way to do it? The rest of the code is in C++.
SELECT item_table.item_name, c1.name AS CatName, c2.name AS ParentCatName
FROM item_table join category_table c1 on item_table.categoryID=c1.categoryID
LEFT OUTER JOIN category_table c2 ON c2.categoryID = c1.categoryParentID
SQL Fiddle: here