Table: colonia_sales
Columns: region
date
label
format
catalog

Question: What date has 0-6700-30838-2-9 for a catalog?
SQL: SELECT "date" FROM colonia_sales WHERE "catalog" = '0-6700-30838-2-9'

Question: What's the date in the United Kingdom having a catalog of reveal50cd/lp?
SQL: SELECT "date" FROM colonia_sales WHERE "catalog" = 'reveal50cd/lp' AND "region" = 'united kingdom'