Transformer reader表中的一个字段拆分为writer表多行数据

Transformer 能否根据reader表中的一个字段拆分为writer表多行数据
如reader表中有一条字段 内容 A,B 数据。拆分为writer表的两条数据A和数据B

No files, tests, or entry points are named. Start by locating the Transformer processing path and the writer row-emission logic, then trace how one reader record becomes output records. Done means a comma-separated value in one reader field produces separate writer rows with the expected values, with coverage for the described A,B case.

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