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	Start -> "应用切换只读状态"
	-> "数据库 a 置入只读状态"
	-> "Extract a" -> Translate -> "Load to b" -> "一致性校验"
	-> "应用切换正常状态" -> "备份数据库 a" -> End;

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		"应用切换只读状态" ;
		"数据库 a 置入只读状态";
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		Translate;
		"Load to b";
		"一致性校验";
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		"应用切换正常状态" ;
		"备份数据库 a";
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	label = "DB a（SQL Server）离线迁移到 DB b（MySQL）";
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