Stairway to ScriptDOM Level 3 - Finding Patterns in the Abstract Syntax Tree
Learn how you can query for patterns in the Abstract Syntax Tree to analyze your code.
2023-02-22 (first published: 2022-06-08)
2,349 reads
Code Analysis
Finding Correlated Rows Using EXISTS or COUNT
Should you always use EXISTS rather than COUNT when checking for the existence of any correlating rows that match your criteria? Does the former really offer "superior performance and readability". Louis Davidson investigates.
2019-11-28
Why you Should Avoid Using the @@IDENTITY Function
Phil Factor demonstrates why SQL Prompt has a 'Best Practice' rule (BP010) that checks for use of the @@IDENTITY function, and suggests less error-prone ways to get the latest identity values used in a table.
2019-09-05
Database Code Analysis
Database code analysis will reduce the number of 'code smells' that creep into your database builds. It will alert the team to mistakes or omissions, such as missing indexes, that are likely to cause performance problems in production. It will allow the Governance and Operations team visibility into production readiness of the code, warning them of security loopholes and vulnerabilities. William Brewer describes the two technical approaches to database code analysis, static and dynamic, and suggests some tools that can help you get started.
2017-08-18
3,546 reads
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Question of the Day
Checking Identities
The DBCC CHECKIDENT command is used when working with identity values. I have a table with 10 rows in it that looks like this:
TravelLogID CityID StartDate EndDate 1 1 2025-01-11 2025-01-16 2 2 2025-01-11 2025-01-16 3 3 2025-01-11 2025-01-16 4 4 2025-01-11 2025-01-16 5 5 2025-01-11 2025-01-16 6 6 2025-01-11 2025-01-16 7 7 2025-01-11 2025-01-16 8 8 2025-01-11 2025-01-16 9 9 2025-01-11 2025-01-16 10 10 2025-01-11 2025-01-16The docs for DBCC CHECKIDENT say this if I run with only the table parameter: "If the current identity value for a table is less than the maximum identity value stored in the identity column, it is reset using the maximum value in the identity column. " I run this code:
DELETE dbo.TravelLog WHERE TravelLogID >= 9
GO
DBCC CHECKIDENT(TravelLog, RESEED)
GO
INSERT dbo.TravelLog
(
CityID,
StartDate,
EndDate
)
VALUES
(4, '2025-09-14', '2025-09-17')
GO
What is the identity value for the new row inserted by the insert statement above? See possible answers