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DataTables, DataViews, and arrays all use approximately the same amount of memory; however, there is a slight difference in speed. Two dimensional and jagged object arrays will be imported slightly faster, while DataTables and DataViews take approximately 10% longer to import. However, DataReaders remain the fastest, since they do not need to read the data into an object before importing it into ExcelApplication.

Use the newest version OfficeWriter

We are always working to improve the efficiency of ExcelWriter. Make sure to use the latest version of the product to take advantage of these improvements. See the OfficeWriter Change Log for more details.