How To Find A Perfect Match
This article presents a way that finds a perfect match in any bipartite graph or shows why one cannot exist.
2021-09-06
2,851 reads
Mathematics
Navigating Trees With CTE
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
7,661 reads
Blogs
Control Flow Restartability in Azure Data Factory
I presented at SQL Saturday Pittshburgh this past weekend about populating your data warehouse...
Monday Monitor Tips: Knowing Your RPO
By Steve Jones
A customer was asking recently about the RPO for their estate, and I showed...
Webinar tomorrow: The Role of Databases in the Era of AI
By Steve Jones
I’m hosting a webinar tomorrow with Rie Merritt from Microsoft. We’ll be talking about...
Forums
Git Repo(s) for SQL Server Database, SSIS, SSAS, SSRS, PowerBI
Hey all, Just wondering how do you guys / girls set up git repo(s)...
best choice for index when creating a composite key
hi everyone I am planning on adding a composite key for my tables. I...
Best Approach to cutover from Test to Live with new columns and tables added
We have a Production/Live version with up-to-date data and a Test version with older...
Question of the Day
STRING_AGG's behavior
Executing the following script (Sql Server 2022), you get the table t0 with 10 rows:
CREATE TABLE t0
( id INT PRIMARY KEY
, field1 VARCHAR(1000)
, field2 VARCHAR(MAX));
INSERT INTO t0
SELECT
gs.value
, REPLICATE ('X', 1000)
, REPLICATE ('Y', 1000)
FROM generate_series(1, 10, 1) gs;
GOWhat happens if you execute the following statements?
select STRING_AGG(field1, ';') within group (order by id) from t0;
select STRING_AGG(field2, ';') within group (order by id) from t0;