Table: train_schedule
Columns: train_no
train_name
origin
destination
frequency

Question: How many trains leave from puri?
SQL: SELECT COUNT("train_name") FROM train_schedule WHERE "origin" = 'Puri'

Question: What train number is heading to amritsar?
SQL: SELECT "train_no" FROM train_schedule WHERE "destination" = 'Amritsar'

Question: How often does a train leave sealdah?
SQL: SELECT "frequency" FROM train_schedule WHERE "origin" = 'Sealdah'

Question: Where does the bg express train end?
SQL: SELECT "destination" FROM train_schedule WHERE "train_name" = 'BG Express'

Question: What's the name of train number 15647/48?
SQL: SELECT "train_name" FROM train_schedule WHERE "train_no" = '15647/48'