The Longest Record of a File

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1

Hello all!

With the utility ADAFIN, I can find out the longest record of a file (in bytes). Here’s the output of my adafin … usage=ds

Records:  Number      =    941,385
          Length: max =      3,170 , min  =         79 , avg    =     417.80

Is there a way to find out the ISN of this 3170-byte-record? I think there is a special reason, why this particular record is so long. But I have to prove this…

My best idea is: make a ADAULD of the whole file and write a script which does the wanted investigations by reading the unloaded file. But this solution would be very time consuming.

Any better ideas?

2

Instead of trying to use Adabas utilities, why not write a little Natural program to read the whole file and get it to tell you.

Peter

3

Because Natural returns decompressed records - they will all be the same length. Your “little program” would have to mimic Adabas’ compression routine. (Perhaps deleting trailing blanks in alpha fileds would be a close-enough approximation.) An unload (without decompression) will give you variable-length records, so you’d be able to find the longest one.

If you’re presuming that the differences in length are a factor of the number of PE and/or MU entries, then the “little program” could list ISNs for the records with the largest count fields (C*).

4

You can get this info - both the compressed and uncompressed length - by writing your own direct call program, either in NAT or C.

If you issue an Lx command, the additions 2 field contains 2 half words, the first being the compressed length and the second is the uncompressed length.

If you write a program in NAT, use the USR1043N interface to make the direct call.

At one time I had a NAT program that read an entire file physically using an L2 call and calculated the longest and average lengths (compressed and uncompressed). A quick cursory look of my personal archive doesn’t find it, but if I do find it, I will upload it.

Kind regards,
Ray Mullins

5

Good hint! This helps me! Here’s my try - it’s working! :slight_smile:

define data local
*
1 CONTROL-BLOCK  (A80)
1 REDEFINE CONTROL-BLOCK
[snip] /* please have a look at USR1043P
1 RESPONSE      (I04)
*
1 #ISN          (I04)
1 #length-B     (B02)
1 REDEFINE #length-B
  2 #COMPRESSED-LENGTH (I02)
*
end-define
*
REPEAT
*
RESET CB-DBID CB-FNR CB-RSP CB-ISN CB-ISL CB-ISQ CB-FBL
      CB-RBL CB-SBL CB-VBL CB-IBL CB-RESERVED
*
  CB-CMD := 'L2'    /* read physical Command
  CB-CID := '0001'  /* Command ID
  CB-RSP := 010     /* UDB
  CB-FNR := 010     /* File
  CB-FBL := H'03'   /* Format buffer length
  CB-RBL := H'01'   /* Record buffer length
  FORMAT-BUFFER := 'AA.'    /* any field
*
  CALLNAT 'USR1043N'
    CONTROL-BLOCK  FORMAT-ADDR  RECORD-ADDR  SEARCH-ADDR
    VALUE-ADDR     ISN-ADDR     RESPONSE
*
  IF RESPONSE = 0
    #length-B := CB-ADD2
    #ISN := CB-ISN
    display CB-ISN CB-ADD2 (EM=HHHHHHHH) #ISN #COMPRESSED-LENGTH
  ELSE
    ESCAPE BOTTOM
  END-IF
*
END-REPEAT
*
IF RESPONSE NE 0 AND RESPONSE NE 3
  WRITE 'ADABAS response code (L2):' RESPONSE
END-IF
*
RESET CB-DBID CB-FNR CB-RSP CB-ISN CB-ISL CB-ISQ CB-FBL
      CB-RBL CB-SBL CB-VBL CB-IBL CB-RESERVED
*
CB-CMD := 'RC'        /* Release Command
CB-CID := H'00000000'
*
CALLNAT 'USR1043N'
  CONTROL-BLOCK  FORMAT-ADDR  RECORD-ADDR  SEARCH-ADDR
  VALUE-ADDR     ISN-ADDR     RESPONSE
*
IF RESPONSE NE 0
  WRITE 'ADABAS response code (RC):' RESPONSE
END-IF
*
END
6

Great! Glad I could help! :smiley:

7

Please to see that a little Natural program solved your issues :lol:

Peter

8

But you have to admit that the ADABAS L2-command does the job, not the NATURAL-Program :wink: