Recently, I had a requirement to update a field with NULL value using APEX Data loader.
There is a setting in Data Loader that allows for updating a field with a NULL value and it’s as follows:
1. Launch Data Loader
2. Select Settings
3. Check box – Insert Null Values.
Then, follow the below procedure:
1. Export the data – include id and Field that should be changed to blank.
2. Delete data contained in column that should be returned as NULL (no values).
3. Save new .csv with new name to avoid overwriting Data Export in Step 1 of this sample process.
4. Run Data Loader Update using new file with Blank values.
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