[sqlite] virtual tables vs. expression-based indexes

I'm considering using a virtual table to query an external-to-SQLite data store. However, I've carefully read about the xBestIndex method, and it appears that virtual tables cannot have indexes on expressions; or rather that the SQLite query engine can't make use of such indexes, only indexes

[sqlite] Virtual Tables xConnect Called When?

The documentation says that "The difference is that xConnect is called to establish a new connection to an existing virtual table whereas xCreate is called to create a new virtual table from scratch." But this leaves me unclear on the circumstances where xConnect would be called (assuming I have a

[sqlite] virtual tables, xBestIndex, pIdxInfo->aConstraint[].op, and 'NOT'...

Folks, I cannot seem to find a means of filtering on negated operators, e.g. <>, not null, not like, etc., in the xBestIndex() method for virtual vables. As best as I can tell, I cannot, unless there is something I am missing, hence this inquiry. In a few virtual tables I have implemented, I

[sqlite] virtual tables, xBestIndex/xFilter question

First, thanks in advance for any help offered. I'm pretty comfortable using sqlite but just now starting to develop with virtual tables. I'm running into troubles and I'm pretty sure it's because my mental model of sqlite is wimpy. I'm trying to build a tool that interfaces to C++ objects in

[sqlite] virtual tables, and theTrue meaning of pIdxInfo->estimatedCost, pIdxInfo->estimatedRows, and pIdxInfo->idxFlags...

Hi folks, I am trying to fully understand the impact and correct use of a few subtle features related to virtual tables' the xBestIndex mechanism, and their correct use. Here are my current beliefs: * pIdxInfo->estimatedCost obviously the cost of the proposed plan; a metric of the

[sqlite] Virtual tables and table-valued functions

6 dec 2015, Charles Leifer: > In working on a Python wrapper around virtual tables, I thought it > might be > beneficial if SQLite provided an official C API for creating simple > table-valued functions. The wrapper could build on the existing > virtual > table APIs and would consist of: > >

[sqlite] Virtual tables and table-valued functions

In working on a Python wrapper around virtual tables, I thought it might be beneficial if SQLite provided an official C API for creating simple table-valued functions. The wrapper could build on the existing virtual table APIs and would consist of: * user supplied list of parameters, which would

[sqlite] Virtual tables/xBestIndex: Is this a bug?

Kennedy Sent: Thursday, June 11, 2015 1:14 AM To: sqlite-users at mailinglists.sqlite.org Subject: Re: [sqlite] Virtual tables/xBestIndex: Is this a bug? On 06/11/2015 03:49 AM, Eric Hill wrote: > Is it a bug that SQLite changes the order of the constraints passed to > xBestIndex based

[sqlite] Virtual tables/xBestIndex: Is this a bug?

On 06/11/2015 03:49 AM, Eric Hill wrote: > Is it a bug that SQLite changes the order of the constraints passed to > xBestIndex based merely on the order of the ON clause, when SQL (AFAIK) says > nothing about what the order of the ON clause should be? No. The order is undefined. However, it is

[sqlite] Virtual tables/xBestIndex: Is this a bug?

Hey, This is a follow-up from the thread entitled "Virtual Table query - why isn't SQLite using my indexes?" in order to raise the visibility of this issue: Consider this SQL, where all of the tables involved are virtual: SELECT t2.rental_id, t2.rental_date, t1.film_id, t3.title,

[sqlite] virtual tables (was : SQLite as a meta database)

Hi there, Since virtual tables were recenty mentioned in the thread "SQLite as a meta database" , I take this opportunity to announce that the lastest version of the DBD::SQLite driver for Perl now has support for virtual tables (see https://metacpan.org/pod/DBD::SQLite ). This means that

[sqlite] Virtual tables and foreign keys

Hi, I need (and have attempted to add) limited support for foreign key constraints mapping to virtual tables. It seems this is not possible currently in sqlite, or at least, it gives me "foreign key mismatch" when I try. My use-case is this: create virtual table vtbl using vtblXYZ; create

Re: [sqlite] virtual tables and group by: how could we prevent to retrieve all rows from a vtab and sort them later ?

James K. Lowden wrote: > Clemens Ladisch wrote: >>> Is there a way to force rows to be dispatched (using the group by) >>> and aggregated on the fly instead of being stored, sorted and then >>> aggregated? >> >> SQLite can optimize GROUP BY this way only if it can prove that

Re: [sqlite] virtual tables and group by: how could we prevent to retrieve all rows from a vtab and sort them later ?

On Thu, 19 Dec 2013 12:03:48 +0100 Clemens Ladisch wrote: > > Is there a way to force rows to be dispatched (using the group by) > > and aggregated on the fly instead of being stored, sorted and then > > aggregated? > > SQLite can optimize GROUP BY this way only if it can

Re: [sqlite] virtual tables and group by: how could we prevent to retrieve all rows from a vtab and sort them later ?

...@sqlite.org [mailto:sqlite-users-boun...@sqlite.org] On Behalf Of Clemens Ladisch Sent: jeudi 19 décembre 2013 12:43 To: sqlite-users@sqlite.org Subject: Re: [sqlite] virtual tables and group by: how could we prevent to retrieve all rows from a vtab and sort them later ? Hick Gunter wrote: >

Re: [sqlite] virtual tables and group by: how could we prevent to retrieve all rows from a vtab and sort them later ?

Hick Gunter wrote: > You are in error on number 4. > > SQLite reads your CFL table once and performs the aggregation in > a temporary table that holds 1 entry per "contract" i.e. about > 1000 rows of max 16 byte records which I estimate to using less than > 64k. > > For each record read, SQLite

Re: [sqlite] virtual tables and group by: how could we prevent to retrieve all rows from a vtab and sort them later ?

or insert the matching row in the temporary table. -Ursprüngliche Nachricht- Von: Perrin, Lionel [mailto:lionel.per...@moodys.com] Gesendet: Mittwoch, 18. Dezember 2013 14:58 An: sqlite-users@sqlite.org Betreff: [sqlite] virtual tables and group by: how could we prevent to retrieve all rows f

Re: [sqlite] virtual tables and group by: how could we prevent to retrieve all rows from a vtab and sort them later ?

Perrin, Lionel wrote: > I plan to use sqlite to implement an 'aggregation tool'. Basically, > the design would be the following: > > 1. I implement a virtual table CFL(contract, amount) which may provide >up to 1 billion unsorted rows. > > 2. The aggregation phasis will be defined at run time

[sqlite] virtual tables and group by: how could we prevent to retrieve all rows from a vtab and sort them later ?

Hello, I plan to use sqlite to implement an 'aggregation tool'. Basically, the design would be the following: 1. I implement a virtual table CFL(contract, amount) which may provide up to 1 billion unsorted rows. 2. The aggregation phasis will be defined at run time and may

Re: [sqlite] Virtual tables are driving me insane!

Thanks OBones! Your link gave me the solution to why my code didn't work! It was (of course) I who made an error in translating function parameters from C to Pascal! Best regards! /Jörgen sqlite-users-requ...@sqlite.org skrev 2012-09-24 18:00: Re: [sqlite] Virtual tables are driving me

Re: [sqlite] Virtual tables are driving me insane!

Hello, have a look at what's here: http://code.google.com/p/sv-utils/wiki/Intro There is a complete and unit tested encapsulation for SQlite and its virtual tables. Regards ___ sqlite-users mailing list sqlite-users@sqlite.org

Re: [sqlite] Virtual tables are driving me insane!

On Fri, Sep 21, 2012 at 11:44:09PM +0200, Jörgen Hägglund scratched on the wall: > I tried creating a super simple test which just return "default" > values on all calls. > This is the order my functions are being called: > xCreate (enter function) > xCreate (exit function) > xConnect (enter

Re: [sqlite] Virtual tables are driving me insane!

Jörgen Hägglund wrote: > I'm trying to implement virtual tables, but I seem to be in over > my head with this. > I get an access violation in SQLite3.dll (reading of address 0008) > > Does anyone have any ideas to what I'm doing wrong? Not really. But one mistake I had made was to read this

Re: [sqlite] Virtual tables are driving me insane!

-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 On 21/09/12 14:44, Jörgen Hägglund wrote: > At this point I get an access violation in SQLite3.dll (reading of > address 0008) You are reading the third member of a structure that is NULL. You should use a debugger that catches this sort of

[sqlite] Virtual tables are driving me insane!

Hi all! First off, my configuration: Windows 7 Ultimate x64 SQLite3 v3.7.14 Amalgamation, compiled to DLL using VS2010 Used directives: SQLITE_4_BYTE_ALIGNED_MALLOC (*) SQLITE_THREADSAFE=2 SQLITE_OMIT_DEPRECATED SQLITE_DEBUG (*) SQLITE_MEMDEBUG (*) (*)

Re: [sqlite] Virtual Tables: xSync without xBegin

On Thu, Jul 12, 2012 at 03:05:39PM +0200, OBones scratched on the wall: > Hello again. > > Does anyone have any suggestion here? There is a footnote in "Using SQLite" (Chapter 10: "Virtual Tables and Modules," p242) on this. The text is: If you do need to support your own

Re: [sqlite] Virtual Tables: retrieving the ppArg given in xFindFunction

Hello, Is there a place where I should enter such a documentation request? Regards Olivier OBones wrote: Hello all, As I'm moving forward in my usage of virtual tables, I'm using the xFindFunction method to overload some functions with my own implementation. That works just fine, but I

Re: [sqlite] Virtual Tables: xSync without xBegin

Hello again. Does anyone have any suggestion here? Regards Olivier OBones wrote: Hello all, I'm pushing my experiment with virtual tables a bit further by trying out the transaction functions. As a result, I gave values for the xBegin, xSync, xCommit and xRollback members of my

Re: [sqlite] Virtual Tables: idxStr parameter for xBestIndex and xFilter

Jay A. Kreibich wrote: On Tue, Jun 26, 2012 at 03:56:33PM +0200, OBones scratched on the wall: Hello all, As I'm experimenting with Virtual Tables, I have had to implement xBestIndex and xFilter. The documentation says that idxNum and idxStr are of no importance to the SQLite core and that

Re: [sqlite] Virtual tables: rename, disconnect and reconnect

Jay A. Kreibich wrote: On Tue, Jun 26, 2012 at 03:47:07PM +0200, OBones scratched on the wall: I would have thought that since the disconnect was given a valid pVTab, this one could have been given back to xConnect when reconnecting the database after its rename. Except SQLite doesn't store

Re: [sqlite] Virtual Tables: idxStr parameter for xBestIndex and xFilter

On Tue, Jun 26, 2012 at 03:56:33PM +0200, OBones scratched on the wall: > Hello all, > > As I'm experimenting with Virtual Tables, I have had to implement > xBestIndex and xFilter. > The documentation says that idxNum and idxStr are of no importance > to the SQLite core and that it's our

Re: [sqlite] Virtual tables: rename, disconnect and reconnect

On Tue, Jun 26, 2012 at 03:47:07PM +0200, OBones scratched on the wall: > Hello all, > > I'm experimenting with virtual tables and I must say that it's a > very nice feature to have, it saves me from inserting millions of > records in a database when I can simply map the source file in > memory

[sqlite] Virtual Tables: xSync without xBegin

Hello all, I'm pushing my experiment with virtual tables a bit further by trying out the transaction functions. As a result, I gave values for the xBegin, xSync, xCommit and xRollback members of my sqlite3_module structure. Then after having registered the module, I sent those two statements:

[sqlite] Virtual Tables: retrieving the ppArg given in xFindFunction

Hello all, As I'm moving forward in my usage of virtual tables, I'm using the xFindFunction method to overload some functions with my own implementation. That works just fine, but I stumbled upon a hurdle that was not obvious to solve at first glance. Inside the xFindFunction, you can give a

[sqlite] Virtual Tables: idxStr parameter for xBestIndex and xFilter

Hello all, As I'm experimenting with Virtual Tables, I have had to implement xBestIndex and xFilter. The documentation says that idxNum and idxStr are of no importance to the SQLite core and that it's our responsibility to make sure xFilter and xBestIndex agree on the meaning. This is fine by

[sqlite] Virtual tables: rename, disconnect and reconnect

Hello all, I'm experimenting with virtual tables and I must say that it's a very nice feature to have, it saves me from inserting millions of records in a database when I can simply map the source file in memory and read it directly. However, I have a small issue when renaming a database.

Re: [sqlite] Virtual Tables and tcl / apsw

On 10/25/2011 04:28 PM, Alexey Pechnikov wrote: 2011/10/25 Dan Kennedy: Not possible. The Tcl interface has no bindings for either the virtual table or VFS interfaces. But why? Is there any technical/ideological problems? None that are insurmountable, I would think.

Re: [sqlite] Virtual Tables and tcl / apsw

2011/10/25 Dan Kennedy : > Not possible. The Tcl interface has no bindings for either the > virtual table or VFS interfaces. But why? Is there any technical/ideological problems? -- Best regards, Alexey Pechnikov. http://pechnikov.tel/

Re: [sqlite] Virtual Tables and tcl / apsw

On 10/25/2011 02:31 PM, sqlite-us...@h-rd.org wrote: Hi, I have some questions on virtual tables and tcl compared to perl and python/apsw. As I understand you can build your own virtual table implementation with apsw (and also with perl). Is this also possible with tclsqlite? Any pointers

[sqlite] Virtual Tables and tcl / apsw

Hi, I have some questions on virtual tables and tcl compared to perl and python/apsw. As I understand you can build your own virtual table implementation with apsw (and also with perl). Is this also possible with tclsqlite? Any pointers greatly appreciated, I could not find it in the

Re: [sqlite] Virtual tables and OR clause

On 05/04/2011 08:58 PM, Schrum, Allan wrote: > Hi Folks, > > Using virtual tables the WHERE clause is broken up and sent to the "best > index" function to determine the best index. Then the "filter" function is > called to perform the actual work. I've noticed that the SQLITE engine seems > to

[sqlite] Virtual tables and OR clause

Hi Folks, Using virtual tables the WHERE clause is broken up and sent to the "best index" function to determine the best index. Then the "filter" function is called to perform the actual work. I've noticed that the SQLITE engine seems to process OR clauses outside of the virtual table process,

Re: [sqlite] virtual tables

On 23 November 2010 17:39, Roger Binns wrote: > -BEGIN PGP SIGNED MESSAGE- > Hash: SHA1 > > On 11/23/2010 02:04 AM, Vivien Malerba wrote: >> The Libgda library (http://www.gnome-db.org) uses virtual tables > > Are you sure?  It looks like an abstraction layer that

Re: [sqlite] virtual tables

-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 On 11/23/2010 02:04 AM, Vivien Malerba wrote: > The Libgda library (http://www.gnome-db.org) uses virtual tables Are you sure? It looks like an abstraction layer that sits above several databases, with similar functionality to ODBC/JDBC. We are

Re: [sqlite] virtual tables

The Libgda library (http://www.gnome-db.org) uses virtual tables to enable one to execute statements on several tables from several database backends (SQlite, PostgreSQL, MySQL, Oracle, Jdbc, SqlCipher, MDB) and CSV files. Regards, Vivien ___

Re: [sqlite] virtual tables

-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 On 11/22/2010 06:59 PM, dcharno wrote: > What are some of the things that people use virtual tables for? Are > there any good example usages? FTS3 uses them. Various CSV extensions do too. With my APSW package I include a virtual table that lets

Re: [sqlite] virtual tables

] On Behalf Of dcharno Sent: 23 November 2010 05:00 AM To: sqlite-users@sqlite.org Subject: [sqlite] virtual tables What are some of the things that people use virtual tables for? Are there any good example usages? ___ sqlite-users mailing list sqlite-users

Re: [sqlite] virtual tables

Am Montag, den 22.11.2010, 21:59 -0500 schrieb dcharno: > What are some of the things that people use virtual tables for? Are > there any good example usages? > ___ > sqlite-users mailing list > sqlite-users@sqlite.org >

[sqlite] virtual tables

What are some of the things that people use virtual tables for? Are there any good example usages? ___ sqlite-users mailing list sqlite-users@sqlite.org http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users

Re: [sqlite] Virtual tables

Got that one two, thanks, this mail list saves time. On 5/6/10, Jay A. Kreibich wrote: > On Thu, May 06, 2010 at 12:31:26AM -0700, Matt Young scratched on the wall: > >> Can I create a virtual table mapped to an existing table in my >> database? > > You'll need to write a fair

Re: [sqlite] virtual tables, how experimental? what's the history of it?

On Thu, May 06, 2010 at 12:10:56PM -0700, Trey Jackson scratched on the wall: > So I was looking at the Virtual Table http://www.sqlite.org/vtab.html > Anyway, can someone provide history on how much has it has changed over > releases, when it was introduced? Just so I have some contextual

Re: [sqlite] Virtual tables

On Thu, May 06, 2010 at 12:31:26AM -0700, Matt Young scratched on the wall: > Can I create a virtual table mapped to an existing table in my > database? You'll need to write a fair amount of code, but yes. > Does this let me alias a whole table? It lets you do pretty much anything you

Re: [sqlite] Virtual tables

I don't think there is anything in the vanilla sqlite to do this, but... Have a look at src/test8.c in the main (not amalgamation) source code... this may give you some ideas. I don't think it does what you want exactly, but a quick skim through makes me think it has some pointers in the right

[sqlite] Virtual tables

Can I create a virtual table mapped to an existing table in my database? Does this let me alias a whole table? Thinking out loud, does this give me ability to write a query on the virtual table, then remap the virtual table to a current table and execute the query?

[sqlite] Virtual Tables problem with queries like to "rowid in (...)"

Hello! This query produce full-scan of the FTS3 virtual table 'data': sqlite> select count(*) from data where rowid in (1); ^CError: interrupted After 30 minuts I cancel the query. sqlite> explain query plan select count(*) from data where rowid=1; 0|0|TABLE data VIRTUAL TABLE INDEX 1: sqlite>

[sqlite] Virtual Tables & Transactions

Documentation error and/or bug: http://sqlite.org/vtab.html#xsync "This method is only invoked after call to the xBegin method..." Not true (3.6.20). An xSync/xCommit pair is given after the initial xCreate call. I'm not sure if that is intentional or not. -j -- Jay A.

Re: [sqlite] virtual tables may not be indexed

On Wed, Aug 5, 2009 at 5:37 PM, Lukas Haase wrote: > Hi list, > > I have a huge problem: A database with 2 HTML fragements should > contain a fulltext index. For that reason I put all data into a virtual > table: > > CREATE VIRTUAL TABLE topics USING fts3( >        topicID

Re: [sqlite] virtual tables may not be indexed

fts has an implicit index on the docid (aka rowid), and a fulltext index on the terms in the columns. All columns are treated as TEXT, you can say INTEGER or VARCHAR, but they are TEXT. The end of this page: http://code.google.com/apis/gears/api_database.html has an example of how you might

[sqlite] virtual tables may not be indexed

Hi list, I have a huge problem: A database with 2 HTML fragements should contain a fulltext index. For that reason I put all data into a virtual table: CREATE VIRTUAL TABLE topics USING fts3( topicID INTEGER, topic_title VARCHAR(200) COLLATE NOCASE, topic TEXT,

Re: [sqlite] Virtual tables

On Sat, 13 Sep 2008 18:36:26 +0200, you wrote: >Exactly Stephen! I was trying to dump a database and I was wondering >how to deal with virtual tables. > >I think that a good way to dump a database skipping internally >generated real tables could be to: >- first create all tables that contains

Re: [sqlite] Virtual tables

Exactly Stephen! I was trying to dump a database and I was wondering how to deal with virtual tables. I think that a good way to dump a database skipping internally generated real tables could be to: - first create all tables that contains the CREATE VIRTUAL TABLE statement - then get the

Re: [sqlite] Virtual tables

Kishor, I think Marco may want to be able to know how to determine which tables in a DB are real tables and which ones below to virtual tables. If you want to do something like dump tables from the database, you do not want to be dumping all the internally generated real tables. It might be

Re: [sqlite] Virtual tables

On 9/13/08, Marco Bambini <[EMAIL PROTECTED]> wrote: > Yes but creating a virtual tables involves the creations of other > related tables ... Well, the FTSn mechanism does all the extra table voodoo for you, so you don't have to be bothered about it. From what it seems like, the other magic

Re: [sqlite] Virtual tables

Yes but creating a virtual tables involves the creations of other related tables ... does all the virtual table implementations (fts1, fts2, fts3) follow the same schema or it is implementation dependent? --- Marco Bambini http://www.sqlabs.net http://www.sqlabs.net/blog/

Re: [sqlite] Virtual tables

On 9/13/08, Marco Bambini <[EMAIL PROTECTED]> wrote: > What is the best way to identify virtual tables inside a sqlite > database? isn't the schema enough? In my world it says CREATE VIRTUAL TABLE ... > > Thanks a lot. > --- > Marco Bambini > http://www.sqlabs.net >

[sqlite] Virtual tables

What is the best way to identify virtual tables inside a sqlite database? Thanks a lot. --- Marco Bambini http://www.sqlabs.net http://www.sqlabs.net/blog/ http://www.sqlabs.net/realsqlserver/ ___ sqlite-users mailing list sqlite-users@sqlite.org

Re: [sqlite] Virtual tables declaration statements

Aladdin > Date: Mon, 5 May 2008 09:59:52 -0500 > From: [EMAIL PROTECTED] > To: sqlite-users@sqlite.org > Subject: Re: [sqlite] Virtual tables declaration statements > > Don't think that will happen. "Dot" notation is used as in > "databasename.tablena

Re: [sqlite] Virtual tables declaration statements

AM To: sqlite-users@sqlite.org Subject: [sqlite] Virtual tables declaration statements Hi list! I've just finished a set of sqlite3 virtual tables and I would like to name them with a "dot notation", ie "data.source1", "data.source2" created like that: sqlite3_create_module(

[sqlite] Virtual tables declaration statements

Hi list! I've just finished a set of sqlite3 virtual tables and I would like to name them with a "dot notation", ie "data.source1", "data.source2" created like that: sqlite3_create_module(db, "data.source1", , 0); sqlite3_create_module(db, "data.source2", , 0); ... and then use the following

[sqlite] Virtual Tables performance

We've begun implementing some virtual tables with latest SQLite build and run into a few questions performance-wise, all these questions revolve around the same issue (join performance). 1) Is there a way to know which fields are going to be potentially requested by xColumn? For instance if I

[sqlite] Virtual tables cannot be used with a shared cache?

In the documentation for sqlite3_enable_shared_cache it says: ** Virtual tables cannot be used with a shared cache. When shared ** cache is enabled, the [sqlite3_create_module()] API used to register ** virtual tables will always return an error. Just curious why is there such a

Re: [sqlite] (Virtual Tables) xFilter - called only once per xOpen ?

"Michael Brehm" <[EMAIL PROTECTED]> wrote: > Hi again, still working on my Virtual Table implementation/object model > here, and I have a question about the relationship between xOpen and > xFilter. By perusing the code and playing around with some sample > statements, it looks to me like there

[sqlite] (Virtual Tables) xFilter - called only once per xOpen ?

Hi again, still working on my Virtual Table implementation/object model here, and I have a question about the relationship between xOpen and xFilter. By perusing the code and playing around with some sample statements, it looks to me like there will only be one call to xFilter for any given

[sqlite] Virtual tables and locking.

hi, Is it possible to add some informations about locking mechanism in the wiki page VirtualTables? I'm facing concurrency problem in developing a cluster Sqlite database. One table per database. Multiple databases indexed like x.db, x.db-001, x.db-002, x.db-003, ... each containing a choosen

Re: [sqlite] Virtual tables

Gerry Snyder wrote: BTW, I really liked the video presentation mentioned on the list recently, not least because I had not been sure how to pronounce SQLite (I had thought it might be ESS CUE LITE instead of the proper ESS CUE ELL (L)ITE) Well, that's really only one person's opinion of

Re: [sqlite] Virtual tables

[EMAIL PROTECTED] wrote: http://www.sqlite.org/cvstrac/wiki?p=VirtualTables This is a feature currently under active development. -- D. Richard Hipp <[EMAIL PROTECTED]> Wow! I really look forward to the day when this and full-text search are ready for prime-time use (including

Re: [sqlite] Virtual tables

Matthew Jones wrote: Is there any straight forward way I could use SQLite3 with virtual tables. By that I mean SQLite contains all the table and index definitions but none of the data - actually it will contain the data for some tables but not others. I only need to query access to the tables

Re: [sqlite] Virtual tables

Matthew Jones <[EMAIL PROTECTED]> wrote: > Is there any straight forward way I could use SQLite3 with virtual > tables. By that I mean SQLite contains all the table and index > definitions but none of the data - actually it will contain the data for > some tables but not others. I only need to

[sqlite] Virtual tables

Is there any straight forward way I could use SQLite3 with virtual tables. By that I mean SQLite contains all the table and index definitions but none of the data - actually it will contain the data for some tables but not others. I only need to query access to the tables so I need to