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<p style="margin-top:0;margin-bottom:0"><span style="background-color:white;">>This will leave your site down between the delete and import of new data.<br>
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>It's also going to be fragile, because using append mode with a file that isn't a diff isn't supported, and if the area has a lot of footpaths, it'll be slower, since >append has to do more work.<br>
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>If you match the SQL delete and osmosis filtering carefully you shouldn't get too many errors, but you've probably got some to do with updates and >changing object types.<br>
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>As long as you're aware of these problems and it works for your needs, I'd say to go for it.</span><br>
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Thanks. I have actually used append frequently over several years and never had a problem with it; main issue is that memory is expensive on servers so I have to do take various less-than-ideal steps to work round low memory.</p>
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<p style="margin-top:0;margin-bottom:0">The intention is to bring the site down over the (say) 2-3 hours the update is taking place; this is what I used to do when I last performed weekly updates. This would be scheduled for (probably) Wednesday 0100-0400 UK
time, a time that the server is likely to see little traffic as it's UK and Ireland oriented; at such time most of Europe will be asleep. Granted there might be a few out-of-Europe visitors at that time; but as my site is quite niche with limited visitors,
I consider this acceptable downtime.</p>
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<p style="margin-top:0;margin-bottom:0">Nick<br>
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<div id="divRplyFwdMsg" dir="ltr"><font face="Calibri, sans-serif" style="font-size:11pt" color="#000000"><b>From:</b> Paul Norman <penorman@mac.com><br>
<b>Sent:</b> 13 November 2018 10:12:58<br>
<b>To:</b> talk@openstreetmap.org<br>
<b>Subject:</b> Re: [OSM-talk] osm2pgsql diff application with filtered OSM data</font>
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<div style="background-color:#FFFFFF">On 2018-11-11 7:53 AM, Nick Whitelegg wrote:<br>
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<p style="margin-top:0; margin-bottom:0">After thinking about this, I realised that I don't really want to update _all_ the data that often. The only thing I need to update on a weekly basis is the footpaths (I'm not so bothered if say the roads, or the pubs
are a year out of date - as long as newly mapped footpaths appear quickly). So what I'm now doing is just doing an osmosis extract of paths weekly, deleting all data in the DB which I class as a 'path' and repopulating in amend mode.</p>
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This will leave your site down between the delete and import of new data.<br>
<br>
It's also going to be fragile, because using append mode with a file that isn't a diff isn't supported, and if the area has a lot of footpaths, it'll be slower, since append has to do more work.<br>
<br>
If you match the SQL delete and osmosis filtering carefully you shouldn't get too many errors, but you've probably got some to do with updates and changing object types.<br>
<br>
As long as you're aware of these problems and it works for your needs, I'd say to go for it.<br>
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