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I am manually editing a Postgis layar with QGIS and would like to export these manual changes in the form of an SQL script. This way:

  • I can do it automatically next time i need to
  • it is easier to work on remote machines where i don't have QGIS

Is this possible?

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What type of manual edits are you making? Spatial edits? Attribute edits? Some more details may help us provide a better answer. – Darren Cope Aug 29 '11 at 12:47
I meant spatial edits. It is easy to manually drag a line in QGIS but to repeat the exact same thing again is practically undoable. – mrg Nov 21 '12 at 7:45
up vote 5 down vote accepted

Don't know how to do it specifically for QGIS, but when I want to know what queries an application is executing, I turn on logging on the database. If you are only interested in seeing update/inserts you can do this:

ALTER DATABASE mygisdb SET log_statement='mod';

Read: for more details

Then check your logs after your QGIS change and copy the statements.

Logs are usually kept in pg_log folder (check your postgresql.conf to be sure).

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This sounds like a very good idea. I will have to try this to see if this works. I will get back here after i have tried your suggestion. – mrg Aug 29 '11 at 17:11
I tried it and it worked! Thank you for your good answer! – mrg Aug 30 '11 at 10:43
It might be handy to know that the output found in the logfile needs a bit of editing before you can use it in an SQL script. Make sure you add E before the bytestring and replace all occurrences of \ with \\ as in: geomfromwkb(E'\\001\\002\\000... – mrg Aug 30 '11 at 17:29

I have no idea to do it automatically with QGIS but I know that you can retrieve WKT geometry just with copy and past data from QGIS to text file. You need to write the SQL part (*UPDATE FROM XXXX SET the_geom='' WHERE id='YY'* ou INSERT).

Hope it helps,


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