understanding null vs blank or empty string values
I've always struggled with figuring out how to filter by fields with nulls vs blanks... for example, if I have a formula to identify if a field is null (this will not work with fields that contain empty strings or blank values, correct...?). I've tried using charlength functions to say (when charlength' is greater than 0 then not blank, etc....) but this doesn't seem to work with null values....
Is there a simple formula/way to identify if a field is blank (regardless of null or empty strings)?
Best Answer
-
CASE WHEN COALESCE(TRIM(`field`), '') = '' THEN 'Blank' ELSE 'Not Blank' END
COALESCE will return the first non-null value it finds, used in this case it's saying if the field is null return an empty string. I've wrapped the field in a trim to remove any leading or trailing whitespaces in case someone has a value of all spaces to ignore. Then it is compared to an empty string after it's been converted.
A more verbose way would be:
CASE WHEN `field` IS NULL or TRIM(`field`) = '' THEN 'Blank' ELSE 'Not Blank' END
NULL is a very specific value. The only way to check for null is to use IS NULL or a COALESCE / IFNULL function to default it to a specific value and compare that value.
Most functions you use on NULL or comparison will result in a NULL value back because NULL represents the absence of data.
**Was this post helpful? Click Agree or Like below**
**Did this solve your problem? Accept it as a solution!**1
Categories
- 7.7K All Categories
- 5 Connect
- 921 Connectors
- 244 Workbench
- 477 Transform
- 1.8K Magic ETL
- 60 SQL DataFlows
- 446 Datasets
- 40 Visualize
- 199 Beast Mode
- 2K Charting
- 8 Variables
- 1 Automate
- 348 APIs & Domo Developer
- 82 Apps
- Workflows
- 14 Predict
- 3 Jupyter Workspaces
- 11 R & Python Tiles
- 241 Distribute
- 59 Domo Everywhere
- 241 Scheduled Reports
- 15 Manage
- 36 Governance & Security
- 28 Product Ideas
- 1.1K Ideas Exchange
- Community Forums
- 14 Getting Started
- 1 Community Member Introductions
- 49 Community News
- 18 Event Recordings
- 579 日本支部