Shortest Paths

Kevin Feasel

2016-07-14

R

Sanjay Mishra and Arvind Shaymsundar tie R to SQL Server to solve a pathfinding problem faster:

In such a case, if a developer were to implement Dijkstra’s algorithm to compute the shortest path within the database using T-SQL, then they could use approaches like the one at Hans Oslov’s blog. Hans offers a clever implementation using recursive CTEs, which functionally does the job well. This is a fairly complex problem for the T-SQL language, and Hans’ implementation does a great job of modelling a graph data structure in T-SQL. However, given that T-SQL is mostly a transaction and query processing language, this implementation isn’t very performant, as you can see below.

The important thing to remember is that these technologies tend to complement each other rather than supplant them.

Related Posts

Building An Image Recognizer With R

David Smith has a post showing how to build an image recognizer with R and Microsoft’s Cognitive Services Library: The process of training an image recognition system requires LOTS of images — millions and millions of them. The process involves feeding those images into a deep neural network, and during that process the network generates […]

Read More

Checkpointing Code For Reproduction

David Smith tells an interesting story about a reproducibility problem with data analysis: Timo Grossenbacher, data journalist with Swiss Radio and TV in Zurich, had a bit of a surprise when he attempted to recreate the results of one of the R Markdown scripts published by SRF Data to accompany their data journalism story about vested interests of Swiss […]

Read More

Categories

July 2016
MTWTFSS
« Jun Aug »
 123
45678910
11121314151617
18192021222324
25262728293031