Table: codina
Columns: name
country
type
moving_from
transfer_window
ends
transfer_fee
source

Question: What country has signed type moving from porto?
SQL: SELECT "country" FROM codina WHERE "type" = 'signed' AND "moving_from" = 'porto'

Question: Which transfer window was moving from borussia dortmund?
SQL: SELECT "transfer_window" FROM codina WHERE "moving_from" = 'borussia dortmund'

Question: What is moving from esp with transfer fee of youth system?
SQL: SELECT "moving_from" FROM codina WHERE "country" = 'esp' AND "transfer_fee" = 'youth system'

Question: What is the transfer window in esp with promoted type and more than 2010 ends?
SQL: SELECT "transfer_window" FROM codina WHERE "country" = 'esp' AND "type" = 'promoted' AND "ends" > 2010