This COBOL system supports more than one type of indexed file. The tables below illustrate the different types available and the features that they support. 
	 
 
	  
	 
Table 1. Indexed Files - Features Supported  
	  
	  
	  
	  
	  
	  
	  
		 
		  |   | 
 
		  Supports Files Logically >4 Gb 
		   | 
 
		  Fast Updates on Files with Multiple Duplicate Keys 
		   | 
 
		  Maximum Occurrences of Duplicate Key Value 
		   | 
 
		  Support for Variable Length Records and Compression 
		   | 
 
		  Separate Index File 
		   | 
 
		
 
	 
 
	  
		 
		  | IDXFORMAT"1" 
		   | 
 
		  No 
		   | 
 
		  No 
		   | 
 
		  65535 
		   | 
 
		  No 
		   | 
 
		  Yes 
		   | 
 
		
 
		 
		  | IDXFORMAT"2" 
		   | 
 
		  No 
		   | 
 
		  No 
		   | 
 
		  65535 
		   | 
 
		  No 
		   | 
 
		  Yes 
		   | 
 
		
 
		 
		  | IDXFORMAT"3" 
		   | 
 
		  No 
		   | 
 
		  No 
		   | 
 
		  65535 
		   | 
 
		  Yes 
		   | 
 
		  Yes 
		   | 
 
		
 
		 
		  | IDXFORMAT"4" 
		   | 
 
		  No 
		   | 
 
		  Yes 
		   | 
 
		  4 G 
		   | 
 
		  Yes 
		   | 
 
		  Yes 
		   | 
 
		
 
		 
		  | IDXFORMAT"8" 
		   | 
 
		  Yes 
		   | 
 
		  Yes 
		   | 
 
		  4 G 
		   | 
 
		  Yes 
		   | 
 
		  No 
		   | 
 
		
 
		 
		  | IDXFORMAT"12" 
		   | 
 
		  Yes 
		   | 
 
		  Yes 
		   | 
 
		  4 G 
		   | 
 
		  Yes 
		   | 
 
		  Yes 
		   | 
 
		
 
	 
 
  
 
 
   
 
   
  
Table 2. Indexed Files - Physical Characteristics  
	  
	  
	  
	  
	  
	  
	  
		 
		  |   | 
 
		  Duplicate Occurrence Records 
		   | 
 
		  Data Record Alignment 
		   | 
 
		  File Pointer Size (bytes) 
		   | 
 
		  Residue Length Field 
		   | 
 
		  Index Node Includes Record Header 
		   | 
 
		
 
	 
 
	  
		 
		  | IDXFORMAT"1" 
		   | 
 
		  No 
		   | 
 
		  1 
		   | 
 
		  4 
		   | 
 
		  n/a 
		   | 
 
		  No 
		   | 
 
		
 
		 
		  | IDXFORMAT"2" 
		   | 
 
		  No 
		   | 
 
		  1 
		   | 
 
		  4 
		   | 
 
		  n/a 
		   | 
 
		  No 
		   | 
 
		
 
		 
		  | IDXFORMAT"3" 
		   | 
 
		  No 
		   | 
 
		  4 
		   | 
 
		  4 
		   | 
 
		  2 
		   | 
 
		  No 
		   | 
 
		
 
		 
		  | IDXFORMAT"4" 
		   | 
 
		  Yes 
		   | 
 
		  4 
		   | 
 
		  4 
		   | 
 
		  2 
		   | 
 
		  No 
		   | 
 
		
 
		 
		  | IDXFORMAT"8" 
		   | 
 
		  Yes 
		   | 
 
		  8 
		   | 
 
		  6 
		   | 
 
		  4 
		   | 
 
		  Yes 
		   | 
 
		
 
		 
		  | IDXFORMAT"12" 
		   | 
 
		  Yes 
		   | 
 
		  8 
		   | 
 
		  6 
		   | 
 
		  4 
		   | 
 
		  Yes 
		   |