user: Question: What is the original air date for the episode viewed by 7.12 million?
Columns: ['Episode', 'Title', 'Directed by', 'Written by', 'Originalairdate', 'Viewing Figures (millions) Sourced by BARB ; includes ITV1 HD and ITV1 +1']
Types: ['real', 'text', 'text', 'text', 'text', 'text']
Sample row: [1.0, '"Case One (Part 1)"', 'John Strickland', 'Ben Court & Caroline Ip', '30 January 2012', '7.35']
SQL:

assistant: SELECT "Originalairdate" FROM "Table" WHERE "Viewing Figures (millions) Sourced by BARB ; includes ITV1 HD and ITV1 +1" = '7.12';