列表对列表，项目对项目—如果可以将源类型转化为目标类型，一个列表可以映射到另一列表，一个项目可以映射到另一项目。

List-to-list, item-to-item - a list can only be mapped to another list, and an item can only be mapped to another item if the source type can be converted to the target type.

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映射表还允许用户将源类型转化成目标类型，或定义常量映射 来将常量设置为目标架构中的项目。

The mapping table also allows the user to convert source types to target types, or define constant mappings that set constant values to items in the target schema.

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架构被自动填充，是因为Assembly Editor理解作为信息源的员工项目的类型。

The schema is automatically populated because the Assembly Editor understands the type of the employees item that is the source of the information.

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