ddl log添加额外的guc信息，避免ddl复制停止

[jd-zhang]

*Issue migrated from trac ticket # 883 www.kunlunbase.com *

component: computing nodes | priority: major

2022-07-07 15:30:21: smith created the issue

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记录ddl时，需要检查如下几个GUC变量的值：

extern  bool standard_conforming_strings;
extern bool mysql_ansi_quotes;
extern int	backslash_quote;
extern bool quote_all_identifiers;

因为这些变量影响着字符串的解析或者生成。

[jd-zhang]

2022-07-07 15:30:29: smith changed status from new to accepted

[jd-zhang]

2022-07-07 15:32:31: smith commented

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例如：

-- 非sql标准模式，将‘\'作为转移字符
set standard_conforming_strings = off;

create table t(a varchar(10) default 'a\n\b\n\c', b int);