我正在尝试将txt文件导入到外部表中，并在蜂巢中添加一个额外的列，例如：

CREATE EXTERNAL TABLE IF NOT EXISTS bs.tbl_bt(
tp_registro string,seq string,num_a string,dt_chamada string,hr_chamada string,num_b string,pt_interconect string,dur_rel_chamada string,dur_tar_chamada string,tp_servico string,vl_liq_chamada string,vl_brt_chamada string,reserva string,'${hiveconf:tez.task.operadora}' as operadora string)
ROW FORMAT SERDE 'org.apache.hadoop.hive.serde2.RegexSerDe'
WITH SERDEPROPERTIES (input.regex = (.{1})(.{10})(.{21})(.{8})(.{6})(.{20})(.{10})(.{7})(.{7})(.{2})(.{11})(.{11})(.{29}).*)
STORED AS TEXTFILE
LOCATION '/gr/Fi/B/${hiveconf:tez.task.operadora}';

我在做什么错了？