Julian Hyde created CALCITE-6281:
------------------------------------
Summary: Add test infrastructure to ensure that Calcite is
consistent with the SQL dialects it is trying to emulate
Key: CALCITE-6281
URL: https://issues.apache.org/jira/browse/CALCITE-6281
Project: Calcite
Issue Type: Improvement
Reporter: Julian Hyde
Add test infrastructure to ensure that Calcite is consistent with the SQL
dialects it is trying to emulate.
Calcite is able to emulate other SQL dialects. For example, it can pretend to
be MySQL by setting "lib=mysql, lex=mysql, conformance=mysql_5". In that mode,
the user would expect there to be a SUBSTR function, and that {{SUBSTR('abc'
FROM 0)}} would [return the empty string, the same as
MySQL|https://github.com/apache/calcite/blob/022d878a73dec796bb72743804a6dded7c239bd3/testkit/src/main/java/org/apache/calcite/test/SqlOperatorTest.java#L9428].
(On Postgres, the same expression returns 'abc'.)
How do we trust that MySQL does indeed have that behavior? How do we find out
if, in a later release, the MySQL team decides to change the behavior. That is
the goal of this case.
We propose to add tests that run expressions on both MySQL and
Calcite-pretending-to-be-MySQL, and ensure that the result is the same on both.
We use [testContainers|https://github.com/testcontainers/testcontainers-java]
to instantiate, via Docker, and instance of MySQL.
See discussion [Ensuring that Calcite is consistent with other SQL
systems|https://lists.apache.org/thread/mxy9p6cy8sssf1sq3gz7zkzm6hsysns5].
--
This message was sent by Atlassian Jira
(v8.20.10#820010)
