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When one to one mapping is enabled the internal ids are used as external ids when not mapped explicitly. When this option is not enabled the id map also acts as a filter . Everything when at least one location is mapped explicitly (using for example <location>). In that case, everything that is not mapped is not imported or exported. When not one location is mapped explicitly, enableOneToOneMapping is enabled by default but is good practice to explicitly configure the xml element.
enableCaseInsensitivity
When case insensitivity is enabled the mapping of external to internal ID's will be case insensitive during imports.
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