Sum all value in multiple database fields

maybe use multiple .eq () functions to find exactly the database line with the result

wixData.query('DatabaseName')
.eq('databaseField',comparisonValue)
.eq('databaseField',comparisonValue) 
.eq('databaseField',comparisonValue)
.find()
.then((results)=>{
 //here you can add what comes back from the database
})