'Return the CREATE INDEX SQL statements for a single model field'

def sql_indexes_for_field(self, model, f, style):

    from django.db.backends.util import truncate_name
    if (f.db_index and (not f.unique)):
        qn = self.connection.ops.quote_name
        tablespace = (f.db_tablespace or model._meta.db_tablespace)
        if tablespace:
            sql = self.connection.ops.tablespace_sql(tablespace)
            if sql:
                tablespace_sql = ('    ' + sql)
            else:
                tablespace_sql = ''
        else:
            tablespace_sql = ''
        i_name = ('%s_%s' % (model._meta.db_table, self._digest(f.column)))
        output = [(((((((((style.SQL_KEYWORD('CREATE    INDEX') + '    ') + style.SQL_TABLE(qn(truncate_name(i_name, self.connection.ops.max_name_length())))) + '    ') + style.SQL_KEYWORD('ON')) + '    ') + style.SQL_TABLE(qn(model._meta.db_table))) + '    ') + ('(%s)' % style.SQL_FIELD(qn(f.column)))) + ('%s;' % tablespace_sql))]
    else:
        output = []
    return output
