Re: [sqlite] SQLite Recursive Common Table Expression suggestion

Yes, but we can live and hope for the day a sqlite project roadmap is disclosed with eponymous vtab API which supports completely dynamic column outputs and a fully featured API for row valued language atoms. When that day comes pivot tables, matrix operations, and other row type introspection

Re: [sqlite] SQLite Recursive Common Table Expression suggestion

On Wed, Mar 8, 2017 at 3:47 AM, petern wrote: > Things have changed somewhat since I wrote those comments. After the > introduction of row values in 3.15 https://www.sqlite.org/rowvalue.html , > at least, now the sqlite ecosystem can cope with efficient vector

Re: [sqlite] SQLite Recursive Common Table Expression suggestion

Further to sqlite pivot function, matrix functions, or any other result set meta query language feature, I commented about this before with a concrete suggestion. The core problem is the awkward complexity of building a completely general virtual table (vtab) based eval("") or meta("") which

Re: [sqlite] SQLite Recursive Common Table Expression suggestion

On Tue, 7 Mar 2017 20:26:41 +0100 Clemens Ladisch wrote: > James K. Lowden wrote: > > Clemens Ladisch wrote: > >> Recursive CTEs make SQL Turing complete. > >> > >> But they cannot do everything. > > > > Isn't that a contradiction? > > Being able to

Re: [sqlite] SQLite Recursive Common Table Expression suggestion

James K. Lowden wrote: > Clemens Ladisch wrote: >> Recursive CTEs make SQL Turing complete. >> >> But they cannot do everything. > > Isn't that a contradiction? Being able to emulate a Turing machine (or a register machine) means that there exists _some_ representation of the

Re: [sqlite] SQLite Recursive Common Table Expression suggestion

On Tue, 7 Mar 2017 13:30:00 +0100 Clemens Ladisch wrote: > Recursive CTEs make SQL Turing complete. > > But they cannot do everything. Isn't that a contradiction? --jkl ___ sqlite-users mailing list

Re: [sqlite] SQLite Recursive Common Table Expression suggestion

Maybe so. Even simpler recursion doesn't get executed, such as a quick poll of the sqlite_master table to trigger a system-wide count(*) of all tables isn't allowed, so it seems that it's held at the gate. Even if I mock up a transaction or a thorough UNION set through a view, I need to output it

Re: [sqlite] SQLite Recursive Common Table Expression suggestion

Reached back into the tape storage in my head for this one, but to paraphrase a movie older than me: the future is in pipes. http://souptonuts.sourceforge.net/readme_sqlite_tutorial.html Note that DRH likes to mention that SQLite is meant to replace fopen() more than a full-bore RBDMS, but I

Re: [sqlite] SQLite Recursive Common Table Expression suggestion

Brian Curley wrote: > What I wonder though is if CTEs could actually serve as a stand-in for the > lack of Dynamic SQL Recursive CTEs make SQL Turing complete. But they cannot do everything. For example, when you want to do a pivot operation, the number of columns is determined by the data, and

Re: [sqlite] SQLite Recursive Common Table Expression suggestion

On Mar 7, 2017 6:56 AM, "Brian Curley" wrote: > I have successfully coupled shell scripts and the CLI I'd love to see examples of this sort of use case and I suspect that there's others who would benefit from seeing how others approach solving some of the common problems.

Re: [sqlite] SQLite Recursive Common Table Expression suggestion

...besides, one might argue that anyone who can programmatically predict the best route for Minesweeper should actually focus on a tool that predicted the lottery (or even elections... ;) What I wonder though is if CTEs could actually serve as a stand-in for the lack of Dynamic SQL, sort of how

Re: [sqlite] SQLite Recursive Common Table Expression suggestion

Simon Slavin wrote: > I’ve seen many amusing examples of using Common Table Expressions to > solve Sudoko puzzles. Has anyone tried using one to suggest the best > next move for Minesweeper ? https://en.wikipedia.org/wiki/Minesweeper_(video_game)#Computational_complexity > have SQLite suggest a

[sqlite] SQLite Recursive Common Table Expression suggestion

I’ve seen many amusing examples of using Common Table Expressions to solve Sudoko puzzles. Has anyone tried using one to suggest the best next move for Minesweeper ? The idea would be to supply a grid with the solution so far in it, and supply the total number of mines, and have SQLite