Get runs a SQL SELECT to fetch a single row from the table based on the primary key(s)
i should be an empty value for the struct to load. keys should be the primary key value(s) for the row to load. If multiple keys exist on the table, the order should match the column order specified in SetKeys() when the table mapping was defined.
The hook function PostGet() will be executed after the SELECT statement if the interface defines them.
Returns a pointer to a struct that matches or nil if no row is found.
Returns an error if SetKeys has not been called on the TableMap Panics if any interface in the list has not been registered with AddTable