Export resultset

[Duncan]

Hi

I have been having trouble exporting a resultset for a linestring table which includes text representation of geometry

I have used Spatialite gui from 4.4.0 and 4.3 in both 64 and 32 bit forms

Including the geometry AsText or ASGeoJson exporting in any format causes the gui to crash with varying degrees of export success, but never finishes

I managed to successfully export to text from the SQLite CLI loading mod_spatialite, which is OK but more work :)

Is this a known issue?

Cheers

Duncan 

[mj10777]

Hard to say without looking at the data that causes the problem.

I vaguely remember a case where this was looked into and resolved (large exports were failing).

But I don't remember if that was before the 4.4.0 release.

If sample Database could be sent, would be helpful.

Mark

Cheers

Duncan 

[Duncan]

Thanks for the response Mark

I tested it on a 10 limit and it worked fine so I guess it has to be a large set.

I ramped it up and got to a limit of 168000 rows before it crashed

The current set is nearly 172000 rows and Currently ~100Mb

Duncan 

[a.fu...@lqt.it]

On Mon, 10 Jul 2017 22:02:55 -0700 (PDT), Duncan wrote:
> Thanks for the response Mark
>
> I tested it on a 10 limit and it worked fine so I guess it has to be
> a
> large set.
> I ramped it up and got to a limit of 168000 rows before it crashed
> The current set is nearly 172000 rows and Currently ~100Mb
>

Hi Duncan,

if you could kindly send me (even in a private and confidential
form) a copy of the DB file causing the problem I'll be glad to
investigate on the exact nature of this issue.

lacking a sample reproducing the issue makes absolutely impossible
any serious debugging.

bye Sandro

[Duncan]

Thanks Sandro & Mark.

I have slimmed down the attributes to reduce the size so it is pretty much just geometry and now only 20 Mb zipped

It's available here for 7 days  https://we.tl/1IMp1BpKLs

Cheers

Duncan

[a.fu...@lqt.it]

On Tue, 11 Jul 2017 00:10:22 -0700 (PDT), Duncan wrote:
> Thanks Sandro & Mark.
>
> I have slimmed down the attributes to reduce the size so it is pretty
> much just geometry and now only 20 Mb zipped
> It's available here for 7 days  https://we.tl/1IMp1BpKLs
>

Hi Duncan,

I've tested your sample using the latest development version
of spatialite_gui on Win7 (both 32 and 64 bit executables)
but I was unable to detect any issue.
Exporting the resultset into a txt/tab file correctly worked
either calling AsText() or AsGeoJson().

further confirm: I've then tested the Iter.Net road network
of Tuscany Region; this is a rather complex dataset (about
90 data columns) including about 400,000 linestrings and
the corresponding database has a size of about 400MB.

yet again, it has been correctly exported as a txt/tab file
using both 32 and 64 bit executables and testing both
AsText() and AsGeoJson().
the exported file has a size of about 500Mb.
it's surely interesting to note that the peak memory
requirement for spatialite_gui never exceeded 32MB,
that is a very comfortable figure.

conclusion: I suppose that the current development
version of spatialite_gui should be considered fully
safe for exporting huge resultsets.

bye sandro

[Duncan]

Thanks for testing Sandro. I guess it might be my setup. I'll try it at home to see if it's any different

Cheers