sql date format

Cast( '2011-07-07' as date ) as convertedDate

convert( datetime, fecha, 103 )

  SELECT DATE_FORMAT("2017-06-15", "%Y"); 

convert (varchar , getdate()-1 , 112)

DATE - format YYYY-MM-DD
DATETIME - format: YYYY-MM-DD HH:MI:SS
TIMESTAMP - format: YYYY-MM-DD HH:MI:SS
YEAR - format YYYY or YY

CONVERT ( data_type [ ( length ) ] , expression [ , style ] )  

DATE - format YYYY-MM-DD