Justin Swanhart wrote:
Hi,
Well an awkward set of UDFs is better than nothing.
Perhaps, but it inhibits adoption greatly, and inhibiting adoption
inhibits testing which inhibits stability, etc, etc, etc...
> Particularly if a web
app could run the commands for users. If Drizzle can host a web
application, that application could manage the creation and upkeep of the
views while calling a rudimentary UDF interface in the background. Flexviews
could also exist entirely outside of the database but for the table change
logging. The change logging is the part that is tightly coupled to the
database implementation.
I forgot about one other change logging requirement:
I have to be able to detect what "transaction id" was generated by my last
COMMIT. The algorithm depends on this to build the compensation queries.
This is already supported in Drizzle. See the Command message's
transaction_context member variable:
unsigned char *raw_bytes= get_some_raw_bytes_from_a_log_file();
Command command;
command.SerializeFromArray(raw_bytes);
cout << command.transaction_context().transaction_id() << endl;
--Justin
On Sat, Jul 18, 2009 at 2:44 PM, Jay Pipes <[email protected]> wrote:
Without additions to the parser, flexviews would have to be implemented as
an awkward set of UDFs...
This needs to happen for a variety of upcoming plugins, actually, including
some of the replication plugins (publisher and subscriber coming shortly).
Without this functionality, plugins are stuck using only the SQL syntax
currently implemented in Drizzle.
A bit of an aside...the Drizzle parser, though less than a third the size
of MySQL's, is still a bit of a rat's nest of code. To make it extensible,
we need to add hooks that enable a plugin's own parser methods to be called
when the kernel's parser hits a token it does not understand. So, instead
of bombing a YYABORT(), it needs to call plugins' registered parse routines,
passing in the token stream.
_______________________________________________
Mailing list: https://launchpad.net/~drizzle-discuss
Post to : [email protected]
Unsubscribe : https://launchpad.net/~drizzle-discuss
More help : https://help.launchpad.net/ListHelp
