Using value from same row in Field Calculator of QGIS

Question

I am using QGIS.

I have an attributetable with several columns.

I want to change the values of column1 if they are NULL with the values of the same row in column5.

case WHEN column1 is NULL THEN 
END

How do I say "use the value from the same row"?

Joseph · Accepted Answer · 2016-06-01 11:56:13Z

13

The field calculator always calculates on a row-by-row basis. So you can use:

CASE WHEN "column_1" IS NULL THEN "column_5"
ELSE "column_1"
END

answered Jun 1, 2016 at 11:56

Joseph

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thibautg · Accepted Answer · 2016-06-02 09:19:11Z

9

You can also use coalesce to replace NULL values from column_1 by column_5.

coalesce("column_1", "column_5")

answered Jun 2, 2016 at 9:19

thibautg

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Knightshound · Accepted Answer · 2016-06-01 14:53:10Z

2

Open the attribute table and make it editable.

Select by expression "column_1" isnull
Along the top of the attribute table you an select in a drop down a column of your choice. Select "column_1"
In the text box available write "column_5"
Click "Update Selected"

answered Jun 1, 2016 at 14:53

Knightshound

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3 Answers 3