Well-formatted scripts are always easier to maintain and enhance readability to high degree. Formatting standards are an important part of coding standards anywhere and if not, they need to be. If there are a large number of scripts this can add up to a significant amount of time needed to maintain them. It is also […]
2021-08-27
8,861 reads
SQL Server 2017 introduced the concept of graph data tables as part of the SQL Server database engine. With SQL Server 2019, there were some enhancements like ‘shortest path’ function and constraints on edge tables that make this feature more usable – although it is far from a full-fledged graph database. Graph tables are essentially […]
2019-12-23
15,184 reads
Temporal tables a.k.a Table Versioning was introduced in SQL Server 2016 and is an easy, convenient way to track changes to data. A good introduction to temporal tables can be found here. One of the key advantages of versioning tables is easy of querying – or getting a ‘single pane of glass’ look of how […]
2019-07-29
14,479 reads
This article is a case study and an attempt to explain an interesting phenomenon with data anomalies that is commonly called Simpson's Paradox.
2017-01-10
3,683 reads
SQL Server 2016 does not allow computed columns to co exist with columnstore indexes and clustered btree indexes on same table.
2016-12-29
874 reads
In this post I will attempt to explore simple commands to manipulate data pulled in from a SQL database into R.
2016-10-20
1,638 reads
Simple steps towards understanding what is an Odds Ratio, and how do we arrive at it using TSQL and R scripts.
2016-08-30
2,489 reads
I’ve been putting together a new PostgreSQL session called “Performance Monitoring for the Absolute...
By Rayis Imayev
(2025-Feb-12) I will jump straight to the problem statement without a "boring" introduction, which, in...
By Steve Jones
I wrote about getting the Redgate Test Data Manager set up in 10 minutes...
Can this baselining and benchmarking sqlserver be done using extended events ? what are...
If this post doesn't meet protocol here, please tell me how to improve as...
I'm a retired IT guy in his 80s fighting boredom by trying to learn...
I have this table and data:
CREATE TABLE [dbo].[SalesTracking]
(
[SalesDate] [datetime] NULL,
[SalesPersonID] [int] NULL,
[CustomerID] [int] NOT NULL,
[PONumber] [varchar] (80) COLLATE SQL_Latin1_General_CP1_CI_AS NULL,
[paid] [bit] NULL,
[total] int
) ON [PRIMARY]
GO
CREATE CLUSTERED INDEX [SalesTrackingCDX] ON [dbo].[SalesTracking] ([SalesDate]) ON [PRIMARY]
GO
INSERT dbo.SalesTracking
(SalesDate, SalesPersonID, CustomerID, PONumber, paid, total)
VALUES
('2024-03-15 10:45:55.067', 1, 1,'PO965' ,1, 100),
('2023-09-24 10:45:55.067', 1, 2,'PO627' ,1, 200),
('2022-07-02 10:45:55.067', 1, 3,'PO6' ,1, 300),
('2022-11-03 10:45:55.067', 1, 4,'PO283' ,1, 400),
('2022-11-26 10:45:55.067', 1, 5,'PO735' ,1, 500),
('2023-04-28 10:45:55.067', 1, 6,'PO407' ,1, 600),
('2022-09-09 10:45:55.067', 1, 7,'PO484' ,1, 700),
('2024-03-13 10:45:55.067', 1, 8,'PO344' ,1, 700),
('2024-04-24 10:45:55.067', 1, 9,'PO254' ,1, 800),
('2022-06-19 10:45:55.067', 1, 10,'PO344',1, 800)
GO
When I run this query, how many unique values are returned for the SalesRank column?
SELECT
st.SalesDate
, st.SalesPersonID
, st.total
, RANK () OVER (PARTITION BY st.SalesPersonID
ORDER BY st.total desc) AS SaleRank
FROM dbo.SalesTracking AS st;
See possible answers