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https://issues.apache.org/jira/browse/CALCITE-2280?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16464922#comment-16464922
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Julian Hyde commented on CALCITE-2280:
--------------------------------------
[~eolivelli], [~eee] (and anyone else interested in contributing queries),
content is more important than format, but a fragment of a
[Quidem|https://github.com/julianhyde/quidem] script should be easy for you to
write. I just finished adding custom commands to Quidem (see
[[QUIDEM-18|https://github.com/julianhyde/quidem/issues/18]]) so now we can add
a custom {{explain-validated-on}} command, and execute scripts that look like
this:
{code}
# Test CONNECT BY (Oracle only)
SELECT *
FROM emp
START WITH mgr IS NULL
CONNECT BY empno = PRIOR mgr;
select(...)
!explain-validated-on oracle
# WITH RECURSIVE (Oracle, MySQL 8 onwards)
WITH RECURSIVE t(n) AS (
VALUES (1)
UNION ALL
SELECT n+1 FROM t WHERE n < 100
)
SELECT sum(n) FROM t;
select(...)
!explain-validated-on mysql8+ oracle
{code}
The "select(...)" before each '!' line is the validated and annotated parse
tree. Don't worry about that line. The Calcite developer will replace it with
the correct output.
Please contribute queries like that by attaching .iq files to this JIRA case.
The more the better!
> Liberal "babel" parser that accepts all SQL dialects
> ----------------------------------------------------
>
> Key: CALCITE-2280
> URL: https://issues.apache.org/jira/browse/CALCITE-2280
> Project: Calcite
> Issue Type: Bug
> Reporter: Julian Hyde
> Assignee: Julian Hyde
> Priority: Major
>
> Create a parser that accepts all SQL dialects.
> It would accept common dialects such as Oracle, MySQL, PostgreSQL, BigQuery.
> If you have preferred dialects, please let us know in the comments section.
> (If you're willing to work on a particular dialect, even better!)
> We would do this in a new module, inheriting and extending the parser in the
> same way that the DDL parser in the "server" module does.
> This would be a messy and difficult project, because we would have to comply
> with the rules of each parser (and its set of built-in functions) rather than
> writing the rules as we would like them to be. That's why I would keep it out
> of the core parser. But it would also have large benefits.
> This would be new territory Calcite: as a tool for manipulating/understanding
> SQL, not (necessarily) for relational algebra or execution.
> Some possible uses:
> * analyze query lineage (what tables and columns are used in a query);
> * translate from one SQL dialect to another (using the JDBC adapter to
> generate SQL in the target dialect);
> * a "deep" compatibility mode (much more comprehensive than the current
> compatibility mode) where Calcite could pretend to be, say, Oracle;
> * SQL parser as a service: a REST call gives a SQL query, and returns a JSON
> or XML document with the parse tree.
> If you can think of interesting uses, please discuss in the comments.
> There are similarities with Uber's
> [QueryParser|https://eng.uber.com/queryparser/] tool. Maybe we can
> collaborate, or make use of their test cases.
> We will need a lot of sample queries. If you are able to contribute sample
> queries for particular dialects, please discuss in the comments section. It
> would be good if the sample queries are based on a familiar schema (e.g.
> scott or foodmart) but we can be flexible about this.
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