To populate the File Size field for existing data, you must run the following script.List<ApttusDocumentVersionDetailc> documentVersionDetails = [select id, ApttusContentIdc from ApttusDocumentVersionDetailc where ApttusContentIdc != null AND (ApttusFileSizec = 0 OR ApttusFileSize_c = null) limit 1]; if(documentVersionDetails.size() > 0) { Apttus.DocumentFileSizeUpdateBatch documentFileSizeUpdateBatch = new Apttus.DocumentFileSizeUpdateBatch(); // Execute DocumentFileSizeUpdateBatch Database.executeBatch(documentFileSizeUpdateBatch); }