A few weeks ago, I ran into aquestion on one of the forums asking for a script that can help the team validate object naming conventions. Immediately, I was able tosympathize with the team.
What happens is that when developers use thegraphical (GUI) tools in the SQL Server Management Studio (SSMS) or via a simple script,they often fail to specify a name toeachindividual constraint.These slips are not intentional developers don’t often realize that each constraint is an independent object because they are ultimately related to another user defined object (a table).
However, when a name is not explicitly specified for aparticular constraint, whatMicrosoft SQL Server does is provide a name by combining the following:
A standard prefix indicating the object (e.g. “DF” for default constraints) 9charactersof the object name 5 characters of the field name Finally, the unique Id of the object, represented in hexa-decimal formatWhile this format will always generate a unique value, it would generate names thatmay not be intuitive. Itis therefore a common practice to review the database code and review for compliance with naming conventions that have been defined in the product/project.
This logic can be leveraged during code reviews/audits toidentify objects wherestandard project naming conventions are not met.
To demonstrate the functionality of the script, Icreate one table with a wide range of constraints none of which have a name specified.
USE [tempdb]; GO IF OBJECT_ID('dbo.ConstraintsWithoutNames','U') IS NOT NULL BEGIN DROP TABLE dbo.ConstraintsWithoutNames; END GO CREATE TABLE dbo.ConstraintsWithoutNames ([RecordId] INT NOT NULL IDENTITY(1,1) PRIMARY KEY CLUSTERED, [RecordName] VARCHAR(255) NULL, [RecordStatus] TINYINT NOT NULL DEFAULT (0) CHECK ([RecordStatus] IN (0, 2, 4, 8)) ); GONow, the following script is a simple string search thatlooks for strings ending with the hexa-decimal representation of the parent object.
USE [tempdb]; GO SELECT * FROM [sys].[objects] AS [so] WHERE [so].[is_ms_shipped] = 0 --Considering user objects only AND [so].[name] LIKE ('%' + REPLACE(CONVERT(NVARCHAR(255),CAST([so].[object_id] AS VARBINARY(MAX)),1),'0x','')) --Only those objects whose names end with the hexadecimal --representation of their object Id
Objects given default constraint names
I hope you found this script useful. Please do share your ideas/scripts that you may be using in your day-to-dayactivities.
Until we meet next time,
Be courteous. Drive responsibly.