Table: vuelta_1994
Columns: stage
winner
general_classification
points_classification
mountains_classification
team_classification

Question: What is the general classification of Mapei-clas in stage 12?
SQL: SELECT "general_classification" FROM vuelta_1994 WHERE "team_classification" = 'mapei-clas' AND "stage" = '12'

Question: Which winner has a P stage?
SQL: SELECT "winner" FROM vuelta_1994 WHERE "stage" = 'p'

Question: Which stage corresponds to Banesto and Tony Rominger?
SQL: SELECT "stage" FROM vuelta_1994 WHERE "team_classification" = 'banesto' AND "points_classification" = 'tony rominger'