Access-control within the database is important for the security of data, but it should be simple to implement. It is easy to become overwhelmed by the jargon of principals, securables, owners, schemas, roles, users and permissions, but beneath the apparent complexity, there is a schema-based system that, in combination with database roles and ownership-chaining, provides a relatively simple working solution.
2015-04-22
6,866 reads
There are several different approaches to automating deployment of SQL Server Infrastructure-as-a-Service virtual machines in Microsoft Azure. Marcin Policht examines an approach that involves uploading or creating a custom operating system image which is well suited for scenarios where you want to deploy a custom-configured SQL Server instance to multiple virtual machines with minimal effort and maximum consistency.
2015-04-21
7,452 reads
One of the most certain ways of going wrong with any relational database is to get data conversion wrong. Implicit data conversion is a good feature for the expert but can cause a lot of trouble to the unwary. These boil down to seven ways of failing to get data conversion right. Rob Sheldon explains and gives sage advice on how to avoid the problems.
2015-04-20
7,337 reads
The job of a DBA requires a fusion of skill and knowledge. To acquire this requires a craftsman mindset. Craftsmen find that the better they get at the work, the more enjoyable the work gets, and the more successful they become. Deliberate practice, Specialization and an appetite for overcoming difficulty are good habits to deliberately adopt to successfully grow those craftsmanlike skills to the point that you become “so good they can’t ignore you”.
2015-04-17
9,586 reads
Using SQL to perform cluster analysis to gain insight into data with unknown groups
2015-04-16
5,183 reads
There are times when you don’t what to return a complete set of records. When you have this kind of requirement to only select the TOP X number of items Transact SQL (TSQL) has the TOP clause to meet your needs. In this article Greg Larsen explores how to select a subset of data from a record set.
2015-04-16
9,580 reads
2015-04-15
535 reads
Spatial Data in SQL Server has special indexing because it has to perform specialised functions. It is able, for example, to break down an indexed space into a grid hierarchy by using a technique called tessellation. This is a rules-based system that, when you compare a shape to an index, works out how many cells in the the grid hierarchy are touched by that shape , and how deep down the grid hierarchy to search. There is powerful magic in Spatial Indexes as Surenda and Roy explain.
2015-04-15
7,242 reads
Aaron Bertrand presents a more elegant to prevent developers from attempting to log into production databases using application logins (and to log any such attempts).
2015-04-14
7,318 reads
It is always bad news if your SQL queries are having to use the SORT operator. It is worse news if you get a warning that sort operations are spilling onto TempDB. If you have a busy, slow TempDB, then the effect on performance can be awful. You should check your query plans to try to eliminate SORTs and never leave a SORT warning unheeded. Fabiano Amorim shows the range of ways of getting information on what is going on with a query that is doing a SORT and when requests are made for memory.
2015-04-13
8,822 reads
By HeyMo0sh
Microsoft Fabric (not to be confused with the more general term “fabric” in DevOps)...
By James Serra
I’m honored to be hosting T-SQL Tuesday — edition #192. For those who may...
By Vinay Thakur
Continuing from Day 2 , we learned introduction on Generative AI and Agentic AI,...
I'm fairly certain I know the answer to this from digging into it yesterday,...
Hi Team, I am trying to refresh the Azure Synapse Dedicated pool from production...
hi everyone I am not sure how to write the query that will produce...
I have some data in a table:
CREATE TABLE #test_data
(
id INT PRIMARY KEY,
name VARCHAR(100),
birth_date DATE
);
-- Step 2: Insert rows
INSERT INTO #test_data
VALUES
(1, 'Olivia', '2025-01-05'),
(2, 'Emma', '2025-03-02'),
(3, 'Liam', '2025-11-15'),
(4, 'Noah', '2025-12-22');
If I run this query, how many rows are returned?
SELECT *
FROM OPENJSON(
(
SELECT t.* FROM #test_data AS t FOR JSON PATH
)
) t; See possible answers