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I work on QGIS 2.2, and I am unable to edit my attribute table to change the field type from string to double.

I have gone through several tutorials. - I can not run the table manager plugin, probably because its latest version is for qgis 2.0, (well it appears broken on my plugin manager UI).

  • I am unable to edit my layer so that I can use the field calculator (as several tutorials stipulated).

  • I am not versed with python to use the python console

marked as duplicate by underdark qgis Jul 12 '17 at 18:07

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To do that is preferable create another field with Double type and copy the string field in it. For example, in the next image, I've created the string field 'myString' (editing session) and I've put in it the value "5.78453'. You can corroborate that the type is string because is left aligned.

enter image description here

In the below image it can be observed the creation of field "myDouble" (editing session) and cloning their values from the 'myString' field.

enter image description here

After Enter, it can be observed that 'myDouble' field was created as expected (and 'myString' field can be erased).

enter image description here

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