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Example 10-7 shows an examination of an alternate record.
You can use the Analyze/RMS_File utility to create an FDL file generally called an analysis file. FDL files created by ANALYZE/RMS_FILE contain statistics about each area and key in the primary sections named ANALYSIS_OF_AREA and ANALYSIS_OF_KEY.
These analysis sections are then used by the Edit/FDL utility in its Optimize script. You can compare the statistics in these sections with your assumptions about the file's use; you may find some places in the file's structure where additional tuning will be possible.