Re: [sqlite] Lazy virtual table creation
On Sat, Mar 17, 2018 at 11:42 PM, Marco Bambiniwrote: > with a bit of work you can use the authorize api in order to know when an > access to a non existing table is performed. > https://sqlite.org/c3ref/set_authorizer.html Interesting work-around, if that works. I.e. whether name resolution to table/column happens before or after the authorizer is called. But it brings up the more general question of knowing which APIs are safe to call inside other APIs, notably when doing schema changes for example. In this case for example, we'd typically be inside a prepare statement, and is it OK to change the schema, potentially affecting that very statement we are currently parsing/resolving/compiling? I.e. API re-entrance but outside the context of multi-threading I guess. --DD ___ sqlite-users mailing list sqlite-users@mailinglists.sqlite.org http://mailinglists.sqlite.org/cgi-bin/mailman/listinfo/sqlite-users
Re: [sqlite] Lazy virtual table creation
Philippe, with a bit of work you can use the authorize api in order to know when an access to a non existing table is performed. https://sqlite.org/c3ref/set_authorizer.html Hope this helps. -- Marco Bambini http://www.sqlabs.com http://twitter.com/sqlabs > On 17 Mar 2018, at 15:53, Philippe Riandwrote: > > We are using virtual tables to provide an SQL access to our data set and this > works very well. But we have potentially "a lot” of virtual tables, with > some even yet unknown when we start the DB. We’d like to create them lazily, > on first access. > Is there a hook we can use so when an SQL statement refers to a non existing > table it asks a callback for a VT definition? It is fine if these dynamic > table requires a specific prefix similar to the "temp” one. > > Regards, > > Phil. > > > ___ > sqlite-users mailing list > sqlite-users@mailinglists.sqlite.org > http://mailinglists.sqlite.org/cgi-bin/mailman/listinfo/sqlite-users ___ sqlite-users mailing list sqlite-users@mailinglists.sqlite.org http://mailinglists.sqlite.org/cgi-bin/mailman/listinfo/sqlite-users
Re: [sqlite] Lazy virtual table creation
On 3/17/18, Philippe Riandwrote: > We are using virtual tables to provide an SQL access to our data set and > this works very well. But we have potentially "a lot” of virtual tables, > with some even yet unknown when we start the DB. We’d like to create them > lazily, on first access. > Is there a hook we can use so when an SQL statement refers to a non existing > table it asks a callback for a VT definition? It is fine if these dynamic > table requires a specific prefix similar to the "temp” one. There is no such hook. Sorry. -- D. Richard Hipp d...@sqlite.org ___ sqlite-users mailing list sqlite-users@mailinglists.sqlite.org http://mailinglists.sqlite.org/cgi-bin/mailman/listinfo/sqlite-users
[sqlite] Lazy virtual table creation
We are using virtual tables to provide an SQL access to our data set and this works very well. But we have potentially "a lot” of virtual tables, with some even yet unknown when we start the DB. We’d like to create them lazily, on first access. Is there a hook we can use so when an SQL statement refers to a non existing table it asks a callback for a VT definition? It is fine if these dynamic table requires a specific prefix similar to the "temp” one. Regards, Phil. ___ sqlite-users mailing list sqlite-users@mailinglists.sqlite.org http://mailinglists.sqlite.org/cgi-bin/mailman/listinfo/sqlite-users