Table: halle_album_sales
Columns: region
date
label
format
catalog

Question: Which Label was cataloged as alca-9013?
SQL: SELECT "label" FROM halle_album_sales WHERE "catalog" = 'alca-9013'

Question: Which Catalog was formated as a CD under the label Alfa Records?
SQL: SELECT "catalog" FROM halle_album_sales WHERE "label" = 'alfa records' AND "format" = 'cd'