Thank you! I consulted Deepseek on resolving this issue in R and it provided a "flowing decompression" method of dealing with this problem. In short, batches of observations are decompressed, imported, selected and stored. When one cycle finishes, a second batch is decompressed while the first batch of decompressed file is deleted, and so on. The stored observations, which is what we finally want yet is distributed as multiple small datasets for the time being, is stacked to form a large one. Can SAS do something like this?
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