-------- Message original --------
Sujet: Re: Web Storage & SQL
Date : Thu, 9 Apr 2009 18:28:10 +0200
De : Giovanni Campagna <[email protected]>
Pour : Ivan Enderlin @ Hoa <[email protected]>
2009/4/9 Ivan Enderlin @ Hoa<[email protected]>:
Hi :-),
Le 9/04/09 17:29, Giovanni Campagna a écrit :
2009/4/9 Boris Zbarsky<[email protected]>:
Giovanni Campagna wrote:
So why not adding a parameter on openDatabase() to specify what kind
of database we want (and what kind of query language we will use)?
I mean something like
openDatabase(name, version, type, displayName, estimatedSize)
where type can be any string
so, for example, type = "sql" uses the standard SQL, type="sqlite"
uses SQLite extensions, type="-vendor-xyz" is a vendor specific
extension, etc.
How does this solve the original "no such thing as standard SQL, really"
issue?
We have a standard SQL, and we have DBMS-specific extensions (for
SQLite, for MySQL, for SQLServer, etc.).
The latest version is "ISO/IEC 9075:2008 Information technology --
Database languages -- SQL", released in 2008, but actively being
revised, according to the ISO page.
As usual, if you want interoperability, you use the existing,
implemented, standard (or you ask the ISO to produce an updated
standard with new features), else you use extensions.
A Database Abstract Layer (DAL, i.e. a system that enables user to select
the Relational Database Management System, RDMS, to use) is a good idea but
it does not sound standard anymore. I mean: we are postponing the problem,
because who, why and how will decide what RDMS must be implemented?
What about XML based database?
Best regards.
First, we have "sql". This is the start of the Database proposals, and
all conforming implementation must expose an SQL interface that is
conforming to the ISO standard I cited before.
Then we could add "xml" and "json" (or other formats) as standard to
be implemented by everyone. This is only a choice of query language
and data model (trees, objects and tables), not of the DBMS (SQLite vs
SQLServer), and I hope this choice will be made by the WebApps Working
Group, as this is the WG chartered for the WebStorage proposal.
Thirdly, we have extension, in the form of "-vendor-dbms". For
example, I may expect that IE will have a "-ms-sqlserver". These
formats are by definition out of standard, but they allow the use of
extensions beyond the ISO SQL standard.
--
Ivan Enderlin
Developper of Hoa Framework
http://hoa-project.net/
Giovanni
