A few years ago I started documenting the syntax differences between the main flavors of SQL. This, eventually, turned into the SQL Functions cheat sheet I have made available on my site (and still refer to regularly).

The main challenge I had creating the cheat sheet was that I didn’t have all these databases installed to experiment with. I had to ask volunteers who worked in specific environments to provide syntax examples for their flavor of SQL.

I was recently researching SQL syntax when a poster linked to a “SQL Fiddle” he had created.  SQL Fiddle is a site that allows you to ‘fiddle’ with SQL statements online, using a variety of common SQL languages. In many cases you can test statements using multiple versions of the same language. That led me to a handful of other sites that do the same thing with a different mix of languages. Here are three of the most complete ones I found, along with the languages they support:

http://sqlfiddle.com
SQL Server, Oracle, MySQL, Postgre, SQLLite

https://dbfiddle.uk
SQL Server, Oracle, MySQL, Postgre, MariaDB, SQLLite, DB2, Firebird, TimeScaleDB, YugabyteDB

https://sqlize.online
SQL Server, Oracle, MySQL, Postgre, MariaDB10, SOQOL

Note, these databases don’t always come with sample tables. You might need to run a statement to create the table(s) you want. Or you may be able to run your queries against the system tables.