Unlocking SQL Compare: Mastering Synonym Comparisons (Not Antonyms!)

Imagine you’re managing database deployments across different environments. You rely on SQL Compare to highlight the disparities and keep everything synchronized. But what if subtle differences are slipping through the cracks? Many users are surprised to discover that SQL Compare, by default, might overlook changes in synonyms, especially when those synonyms point to different objects across development and production. This isn’t a flaw, but rather a default setting designed to streamline deployments. However, understanding and adjusting this setting is crucial for accurate database comparisons. While we’re focused on comparing synonyms, it’s important to note we’re not looking for antonyms – opposites – but rather discrepancies in their definitions across environments. Let’s dive into how to ensure SQL Compare accurately detects these vital synonym variations.

The Scenario: Synonym Secrets Across Environments

Consider a common database development scenario. You might have synonyms defined in your development databases that point to objects within the same environment. For instance, in a development setup, you might have two databases, Sales_Feature and Finance_Feature. Within Sales_Feature, a synonym could be created to reference a table in Finance_Feature. This setup works seamlessly in development.

However, when moving to production, the database structure often mirrors the environment but with different names, like Sales and Finance. The synonym, ideally, should now point to the Finance database in production. The underlying object might be conceptually the same, but the server or database location has changed. While this scenario presents development lifecycle considerations, our immediate concern is ensuring SQL Compare recognizes this change as a difference between environments.

Let’s illustrate this with a practical example using SQL Server. We’ll create two databases, SimpleTalk_1_Dev and SimpleTalk_5_Prod, on the same instance for simplicity, mimicking a dev and prod comparison.

First, in our SimpleTalk_1_Dev database, we create a synonym dbo.MyTable that points to Compare1.dbo.MyTable:

USE [SimpleTalk_1_Dev]
GO
CREATE SYNONYM dbo.MyTable FOR Compare1.dbo.MyTable
GO

Next, we create a similar synonym in SimpleTalk_5_Prod, but this time, it points to Compare2.dbo.MyTable:

USE [SimpleTalk_5_Prod]
GO
CREATE SYNONYM dbo.MyTable FOR Compare2.dbo.MyTable
GO

Now, if you were to run a comparison between SimpleTalk_1_Dev and SimpleTalk_5_Prod using SQL Compare with default settings, you might be surprised by the result: no differences are reported for these synonyms. This is despite the synonyms clearly pointing to different target objects.

Unveiling the Solution: The “Ignore” Option

The reason SQL Compare might initially miss these synonym differences lies in a specific project option. SQL Compare is intelligently designed to handle deployments across environments, anticipating that database and server names might legitimately differ between development and production. Therefore, by default, it assumes that variations in these components of a synonym definition are intentional and not necessarily differences that need flagging.

To uncover the hidden differences in our synonym example, we need to adjust the project settings in SQL Compare. When you configure your SQL Compare project, navigate to the “Options” tab. Scroll down within the options list, and you’ll find the setting labeled “Ignore database and server name in synonyms.” This option is checked by default.

By unchecking the “Ignore database and server name in synonyms” option and re-running the comparison between SimpleTalk_1_Dev and SimpleTalk_5_Prod, the result transforms dramatically. SQL Compare now accurately identifies the synonym definitions as different, highlighting the intended change in the synonym’s target.

This adjustment is particularly valuable when comparing databases across different instances, even if the database names themselves remain consistent. This scenario, involving instance name variations, is arguably even more prevalent in real-world deployments.

Extending the Solution Across Redgate Tools

This crucial “Ignore database and server name in synonyms” option isn’t exclusive to SQL Compare. It’s a core setting within the SQL Compare engine, which powers a suite of Redgate products designed for database development and deployment automation. Therefore, you’ll find this same option and its behavior in tools like SQL Change Automation, SQL Source Control, Flyway Desktop, and Redgate Deploy’s automation components.

If you’re experiencing situations where synonym changes aren’t being detected or deployed as expected within these Redgate tools, verifying and potentially unchecking this “Ignore database and server name in synonyms” option should be a primary troubleshooting step. Ensuring this setting aligns with your comparison needs is key to leveraging the full power of SQL Compare and its related tools for accurate and comprehensive database change management.

If you’re looking to streamline your database development and deployment processes with robust DevOps practices, consider exploring tools that can simplify these tasks. Download a trial of Redgate Deploy and discover how it can enhance your database lifecycle management.