SAS Exam A00-212 Topic 3 Question 5 Discussion

T he YES or CHAR setting for the COMPRESS= option uses the RLE compression algorithm. RLE compresses observations by reducing repeated consecutive characters (including blanks) to two-byte or three-byte representations. Therefore, RLE is most often useful for character data that contains repeated blanks. The YES or CHAR setting is also good for compressing numeric data in which most of the values are zero

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