Outputs 'null', unexplained

[OndraZizka]

crunch -in existing-supposedly.csv -as e -in ddb-tenants-LIVE.csv -as l -sql 'SELECT e.* FROM e LEFT JOIN l ON e.a = l.a'

Version 2.10.1 just outputs:

INFO:  * Next CSV input: :
    originalImportArgument: (l) [CSV from FILE_SUFFIX]  <- ddb-tenants-LIVE.csv /
    originalInputPath:      ddb-tenants-LIVE.csv
    tableName:              l

INFO:  * Next CSV input: :
    originalImportArgument: (e) [CSV from FILE_SUFFIX]  <- existing-supposedly.csv /
    originalInputPath:      existing-supposedly.csv
    tableName:              e

null
  If you believe this is a bug, feel free to report it at https://github.com/OndraZizka/csv-cruncher/issues
  but please check the open tickets first.