Pentaho数据集成-Excel Writer输出文件大小

Question

Is PDI inefficient in terms of writing excel xlsx file with Microsoft Excel Writer.

A transformed excel data file in Pentaho output seems to be three times the size, if the data was transformed manually. Is this inefficiency expected or is there a workaround for it.

A CSV file of the same transformed output is way smaller in size. Have I configured something wrong ?

Answer 1

xlsx files should normally be smaller in size than CSV, since they consist of XML data compressed in ZIP files. Pentaho's Microsoft Excel Writer uses org.apache.poi.xssf.streaming.SXSSFWorkbook and org.apache.poi.xssf.usermodel.XSSFWorkbook to write xlsx files, and they create compressed files so this should not be your issue.

To check the files you could check with a zip utility, to see the file sizes and compression rate, to see if there is a bug. You could also try to open the file in Excel and re-save it, to see if that gives a smaller size, which could indicate an inefficiency.