gbk转utf8方案

@zhouweibo  Hi Weibo,

I build an environment by myself, but I can't reproduce your error.

I created a table in this way:

-- Create database if not exists
CREATE DATABASE IF NOT EXISTS upidb;

-- Create table with correct syntax
CREATE TABLE IF NOT EXISTS upidb.gscs_tbl_fultrans_2_db (
    trace_num STRING COMMENT 'Trace number',
    acq_ins_cde STRING COMMENT 'Acquiring institution code',
    fwd_ins_cde STRING COMMENT 'Forwarding institution code',
    acq_trans_cde STRING COMMENT 'Acquiring transaction code',
    iss_trans_cde STRING COMMENT 'Issuing transaction code',
    pri_acct_num STRING COMMENT 'Primary account number',
    resv_fld2 STRING COMMENT 'Reserved field 2 - contains encoded data',
    sett_dt STRING COMMENT 'Settlement date in YYYYMMDD format'
)
COMMENT 'Full transaction table for settlement date partition'
STORED AS PARQUET;

-- Insert sample data with GBK encoded characters to reproduce the encoding issue
INSERT INTO upidb.gscs_tbl_fultrans_2_db VALUES
(
    '123456789012',
    'ACQ001',
    'FWD001',
    'TRANS001',
    'TRANS002',
    '1234567890123456',
    'ABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789测试中文字符ABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ',
    '20231201'
);

Then ran the SELECT sql, but Can't reproduce error:

SELECT trace_num
      ,acq_ins_cde
      ,fwd_ins_cde
      ,acq_trans_cde
      ,iss_trans_cde
      ,pri_acct_num
      ,trim(SUBSTR(resv_fld2,111,2))
      ,trim(decode(SUBSTR(encode(resv_fld2,'gbk'),113,15),'gbk'))
      ,trim(decode(SUBSTR(encode(resv_fld2,'gbk'),128,40),'gbk'))
      ,trim(decode(SUBSTR(encode(resv_fld2,'gbk'),168,40),'gbk'))
from upidb.gscs_tbl_fultrans_2_db
where sett_dt = '20231201'

Can you please share your DDL?