Add unit test for cross-join as there was no one currently.
In the first test-case I test composition of two cross-joins.
In the second test-case I test cross-join with on statement.
I found out that cross-join with on is only valid for MySQL
and sqlite3 so the test includes only these (it is weird to use
cross-join with on anyhow).
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.