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- 【TiDB 版本】：v4.0.2
- 【问题描述】： tidb v4.0.2版 lightning处理包含转义字符 \ 的字段有bug .
数据原文 部分内容 “退（离）休人员”;"";"\";"";
tidb-lightning.toml 相关内容
[mydumper.csv]
separator = ‘;’
delimiter = ‘"’
header = false
not-null = false
null = ‘’
backslash-escape = true
trim-last-separator = false
导入时错误如下：
[2020/07/27 09:31:34.864 +08:00] [ERROR] [parser.go:162] [“syntax error”] [pos=264546868] [content=“15001234510”;“fyhxxx”;“2”;“子”;“11234512345”;“hpq云jj29-1 1-6-1”;"";"";"";"";"";“29-1 1-6-1”;"";"";"";"";“9-1 1-6-1”;"";"";"";"";"";"";“必填项”;“29-1 1-6-1”;"";"";"";"";"";"";"";“和\ufffd”]
[2020/07/27 09:31:34.865 +08:00] [ERROR] [restore.go:1001] [“encode kv data and write failed”] [table=test.hai_aprnot_info] [engineNumber=0] [takeTime=12.53145859s] [error=“in file /data2/tmpdata/test.hai_aprnot_info.csv:0 at offset 264546868: syntax error: cannot have consecutive fields without separator”]
[2020/07/27 09:31:34.865 +08:00] [ERROR] [restore.go:848] [“restore engine failed”] [table=test.hai_aprnot_info] [engineNumber=0] [takeTime=12.53151277s] [error=“in file /data2/tmpdata/test.hai_aprnot_info.csv:0 at offset 264546868: syntax error: cannot have consecutive fields without separator”]
[2020/07/27 09:31:34.865 +08:00] [ERROR] [restore.go:870] [“import whole table failed”] [table=test.hai_aprnot_info] [takeTime=12.531569055s] [error=“in file /data2/tmpdata/test.hai_aprnot_info.csv:0 at offset 264546868: syntax error: cannot have consecutive fields without separator”]
[2020/07/27 09:31:34.865 +08:00] [ERROR] [restore.go:610] [“restore table failed”] [table=test.hai_aprnot_info] [takeTime=12.574043636s] [error=“restore tabletest.hai_aprnot_infofailed: in file /data2/tmpdata/test.hai_aprnot_info.csv:0 at offset 264546868: syntax error: cannot have consecutive fields without separator”]
根据tidb文档，backslash-escape = true时， 其他情况下（如 \" ）反斜线会被移除，仅在字段中保留其后面的字符（ " ） ，也就是说\ 被去除，后边的” 被保留，但当 \ 后边的 ” 是界定符时，” 未被识别为界定符，解析出错
将 backslash-escape = flase 后，解析正确。请审核是否是bug，还是我理解有问题。
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