Grafana should not allow empty values for variable selection to avoid template errors

Grafana MSSQL
,
2

Maybe I’m way off but are you filtering a Graph with a SQL Fed Variable

Like this “Variable”

SELECT metric 
FROM Table
GROUP BY metric

Then in the Graph

SELECT time, metric, value
FROM Table
WHERE metric IN ( $metric )
ORDER BY time DESC

I’ve done similar filters but with Nulls/Blanks in Data I’ve had to handle them myself

-- FILTER
SELECT CASE WHEN metric IS NULL OR metric IN ( '',' ' ) 
           THEN 'BLANK' 
           ELSE metric 
           END
FROM Table
GROUP BY metric

-- GRAPH
SELECT time, metric, value
FROM Table
WHERE CASE WHEN metric IS NULL OR metric IN ( '',' ' ) 
           THEN 'BLANK' 
           ELSE metric 
           END IN ( $metric )
ORDER BY time DESC

Hope I’m not way off and it’s some help