Monday 2 September 2019

How do you speed up creating new field in attribute table for huge amount of data in QGIS?



In my attribute table for a shapefile, I am converting one field (Julian day) to another field (date) using the field calculator but I'm working with about 7.7 million rows. QGIS has been running for about 17 hours and is half way done. Is there a way to speed up this process? I have QGIS 2.14.19 Essen, not sure if upgrading to 2.18 would be faster.



Answer



Don't do it through the attribute table, or with any attribute tables open. Instead create new attributes directly though layer properties or via the field calculator from the main window.


Adding/deleting columns with attribute tables open is super-slow.


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