2011-01-28 (first published: 2011-01-11)
1,794 reads
T-SQL
Contiguous Time Periods
It is always more efficient to maintain referential integrity by using constraints rather than triggers. Sometimes it isn't obvious how to do this. Until a recent idea by Alex Kuznetsov, the history table presented problems for checking data that were difficult to solve with constraints. Joe Celko explains.
2011-01-11
3,294 reads
2011-01-10
2,923 reads
2011-01-06
2,826 reads
2011-01-04
3,425 reads
Identity Property Range Checking in SQL Server
This article examines practical methods of managing and monitoring large tables which make use of the IDENTITY property.
2011-01-04
3,913 reads
2011-01-03
3,474 reads
2010-12-30
2,952 reads
Understanding T-SQL Expression Short-Circuiting
Understanding the basics of how T-SQL logic works in branching is important to ensure you code works as expected. This article will help you learn how this impacts control of flow language.
2013-06-21 (first published: 2010-12-30)
33,580 reads
Improving 2D Range Query Performance in SQL Server
When using the BETWEEN operator on multiple columns, you are likely using a 2D range query. Such queries perform very poorly in SQL Server. This article examines rewriting these queries for improved performance.
2010-12-30
3,442 reads
Blogs
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Question of the Day
Fun with JSON I
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