T-SQL

External Article

Purging Data from a Large Table in SQL Server

  • Article

Purging data from a table is a common database maintenance task to prevent it from growing too large or to stay in compliance with data retention. When dealing with small amounts of data, this can be accomplished by a simple delete with no issues; however, with larger tables, this task can be problematic. Deleting records requires a lock that can block other processes from writing or even reading the data (depending on your isolation level). In this article I will share a technique I have used to work with some very large tables.

2025-06-04

External Article

Evaluating the Randomness of SQL Server Random Number Functions

  • Article

Microsoft provides T-SQL developers with three functions (rand, newid, and crypt_gen_random) for generating random numbers. Each of these functions is effective at returning random values, but feature sets associated with each function make them best suited to different use cases. This tip’s Solution section presents an overview of common use cases for random numbers in SQL Server along with references to learn more about random numbers in SQL Server.

2025-05-12

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Question of the Day

The Tightly Linked View

I try to run this code on SQL Server 2022. All the objects exist in the database.

CREATE OR ALTER VIEW OrderShipping
AS
SELECT cl.CityNameID,
       cl.CityName,
       o.OrderID,
       o.Customer,
       o.OrderDate,
       o.CustomerID,
       o.cityId
 FROM dbo.CityList AS cl
 INNER JOIN dbo.[Order] AS o ON o.cityId = cl.CityNameID
GO
CREATE OR ALTER FUNCTION GetShipCityForOrder
(
    @OrderID INT
)
RETURNS VARCHAR(50)
WITH SCHEMABINDING
AS
BEGIN
    DECLARE @city VARCHAR(50);
    SELECT @city = os.CityName
    FROM dbo.OrderShipping AS os
    WHERE os.OrderID = @OrderID;
    RETURN @city;
END;
go
What is the result?

See possible answers