Introduction This article celebrates a classic algorithm [1] of Dijkstra (1930 – 2002) which finds a path of minimal cost between any pair of nodes in an undirected graph. His procedure is widely recognized as a fundamental tool for examining communication and transportation networks (eg. Google Maps) and is surprisingly simple. By his own admission, […]
2024-01-05
8,833 reads
Introduction The sp_HorizontalTree procedure introduced here may be used to audit tables with dependent columns. A column is dependent on another if the meaning of the first column depends on the meaning of the second. For example, in a table containing accounting information, the meaning of a Fiscal Quarter column depends on the Fiscal Year to […]
2023-06-16
2,478 reads
Introduction This article shows how to script a basic merge between two tables, without using MERGE. This can be handy when you're merging a pair of tables with hundreds of columns, since the script doesn't know anything about them. This technique introduces and populates some auditing columns (IS_DELETED, IS_INSERTED, IS_UPDATED, TRANSACTION_DATE) for each record, and runs fast. […]
2023-02-20 (first published: 2020-04-14)
18,868 reads
In this article, Glen Cooper provides code that allows you to process a tree, or undirected graph of data. Lots of hierarchies fall into this category and the ability to process them is valuable in many reporting situations.
2023-01-20
3,430 reads
Learn a little basic graph theory in this article that replaces a GROUP BY clause.
2022-07-04 (first published: 2019-10-17)
12,070 reads
This article presents a way that finds a perfect match in any bipartite graph or shows why one cannot exist.
2021-09-06
3,011 reads
Introduction This article shows how common table expressions (CTE) in SQL Server are naturally suited for navigating trees, such as finding its longest path, or diameter. Recall that a tree is an undirected graph where unique paths exist between any two nodes (i.e. vertices). Any node may be selected as its top node, with its […]
2021-04-19
8,248 reads
This article shows how to solve a gaps and islands problem using simple algebra.
2020-03-10
5,085 reads
In this article, we see how SQL can be used to determine matches between two groups, given a set of preferences.
2020-01-23
7,248 reads
An interesting tutorial for linking SQL Server to a Blackberry device and viewing images.
2011-02-09
11,483 reads
By Steve Jones
I had seen these roles in various instances, but never dug into the new...
By Brian Kelley
During COVID, I attended training on software/enterprise architecture given by Mark Richards. One of...
For me, the objective is straightforward: have a backup strategy that is reliable, understandable,...
Comments posted to this topic are about the item Pay for Performance, which is...
Has anyone encountered recurring request latency when using Microsoft Access with SQL Server 2025...
Comments posted to this topic are about the item The ##MS_DatabaseConnector## User
On SQL Server 2025, I run this code as a sysadmin:
CREATE LOGIN Demo WITH PASSWORD = 'Demo1234567' GO ALTER SERVER ROLE ##MS_DatabaseConnector## ADD MEMBER Demo GOI then login as Demo and run this:
USE sandbox go SELECT CURRENT_USERWhat is returned? See possible answers