Syntax differences between one DBMS and another

General Discussion
1

When we generate a changelog for SQL Server and attempt to upload it to another DBMS such as Postgres, there are many errors. The biggest difficulty here is taking all of our SQL Server-based code that shows up after generating a changelog. This appears within the sql tags used in createView, and translating it to Postgres language doesn’t seem easy. In addition there are a number of functions and datatypes referenced within the XML parameters that need to be updated to switch DBMSs. Is there some way when generating a changelog to have it generate in a specified SQL language, as opposed to simply using the language of the source DB?

2

If I’m not mistaken, the source DB is automatically determined from the jdbc-string in the url.

3

Thanks for the response! So, actually, I specifically do NOT want it in the language of the source DB. You’re right that it seems to correctly figure out the source DB. But I want it to then generate in the language of a different DB that I specify in the properties file or generateChangeLog command.

I.e. Migrating from SQL Server DB to Postgres DB

4

Liquibase will only generate syntax for the target database type specified in the url. Converting between dbms platform-specific code is not really a use-case for Liquibase.

5

Good to know Daryl! So currently I use the “url” property within my properties file for generating the changelog, but I do not use the “referenceUrl” property. Could I potentially specify my Postgres DB in “url” and my SQL Server DB in “referenceUrl”, to then get the changelog to generate my SQL Server DB information in a Postgres DB format?

6

I do not think that use case is supported, but you will need to test it.

7

Just tested it in both ways, switching which DB was the referenceUrl. Neither way worked the way I would like. :frowning:

8

I was pretty sure it wouldn’t work. Liquibase is not really a dbms code-conversion tool.