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  Java "SQL parser"

on groups.google.com, sort by date.  There doesn't seem to be
terrifically high demand for this, oddly.  Even so, I find myself in
need of one.

The most common reference I've seen is to something called ZQL.
However, half the time, the link to it goes 404.  The other half of
the time, I find something several years old, and apparently quite
incomplete.

I've been lending some consideration for about a week now to beginning
an open-source Java SQL parser project on Sourceforge.  I would go for
pure SQL2 compliance (using the docs I found at
http://www.contrib.andrew.cmu.edu/~shadow/sql/sql1992.txt and
http://www.contrib.andrew.cmu.edu/~shadow/sql/sql2bnf_aug92.txt as
guides).  I would try to implement the parser in such a way that it
could subclassed reasonably easily, to allow vendor-specific parsers,
as well as a SQL3-compliant version.  I'm sure this would be a massive
undertaking.  The BNF doc alone is over 60Kb.

I'm ambivalent on whether to use JavaCC - it's the only parser
generator I know of, but I know it only by name. I would also guess
it's very generic; it wouldn't generate instances of a nice
SQL-specific class library (I think; I skimmed the FAQ).  I went to
the JavaCC Grammar Repository, and found two SQL grammars, but they're
both Oracle-specific.

Would there be any community interest in an OS Java SQL parser
project?

Paul Brinkley

http://www.antlr.org/

They also have a SQL grammar.

In the long run we want an SQL layer on top of our object
query API...
http://sourceforge.net/projects/sodaquery
...and we will certainly need an SQL parser.

I can't promise to contribute any work immediately though.

Before you start writing your own parser, you should definitely
take a look at this project:
http://ldbc.sourceforge.net

I believe it includes a parser but I don't know how well it works.

Kind regards,
Carl
--
Carl Rosenberger
db4o - database for objects - http://www.db4o.com

The problem I have with any generic parser is that it won't
automatically generate any nice Java classes.  For example, I'd want
these hypothetical classes:

Insert
Delete
Select
SelectInto
CreateTable
etc.

All of these would inherit the appropriate superclasses (say,
DDLStatement, SQLStatement, etc.), and implement appropriate methods
(Select might implement getTables, getColumns, getSearchCondition,
etc.).  This is ultimately what I'm looking for.

Naturally, I wouldn't expect a generic parser to do this.  :-)  But I
would probably like to leverage an existing grammar tool, be it ANTLR,
JavaCC, or something else, and build software that outputs the nice
Java objects I'm looking for.

So here's a rephrasal.  What is the interest level in an open-source
Java SQL Parser that outputs classes as above?  And should it be built
using an existing grammar tool (probably, for sanity's sake), and if
so, which one?

Paul Brinkley

Quote:

>Before you start writing your own parser, you should definitely
>take a look at this project:
>http://ldbc.sourceforge.net

>I believe it includes a parser but I don't know how well it works.

Paul Brinkley

Kind regards,
Carl
--
Carl Rosenberger
db4o - database for objects - http://www.db4o.com