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Controls how the join column for Sample MetaData and Clinical Data is inferred. By default, this value is set to True and when the Sample MetaData table contains > 10,000 records, a random sampling of 500 records will be used to infer whether the join should be on the SubjectIDColumn or the primary sample ID column. If the Clinical Data table is identified by SubjectIDColumn but none of the records happen to be in this random sampling of 500 records from the Sample MetaData table, the join will default to the primary sample ID column. By setting this value to False, all Sample MetaData records will be used instead of only 500.
When the Clinical Data table has many records, setting this value to False may result in the loading of the Land each time Array Studio is connected to Array Server being slow. Typically when the Clinical Data table has many records, it is safe to set this value to True to speed up the loading.