Re: Which delete statement is faster?

Jan-Erik Söderholm wrote:

JF Mezei wrote:
briggs@xxxxxxxxxxxxxxxxx wrote:
In article <13h9vel51sekc1b@xxxxxxxxxxxxxxxxxx>, "Mike Minor"
<mminorhsd@xxxxxxxxxxxxx> writes:
Is there any difference in the speed at which the command is executed
in the following examples?

del a*.*;*
del a*.txt;*
del a*.txt;1

I think that a non-wildcarded delete will be the fastest since it can do
a direct lookup. (but this is not in your example)

In the above cases, the delete command would still have to sequentially
scan all files in the directory beginning with "a" and then see if it
matches the mask. Obviously, the more "*" you have in a mask, the more
CPU will be needed to decide if a full file spec matches the wildcard,
but unless you are running an All Mighty Microvax II, you might not see
any difference since the delete command will spend the most time in IO
and the CPU time needed to check a string against a wildcard
specification is fairly trivial.

Note also that if you'd like to delete *all* files in the
directory, The DELETE option in DFU is (claimed to be) much
faster then DCL DELETE.

....; however, be VERY CAREFUL which DFU version you use.

V2.7-1 can't handle big trees. It will crash and leave a mess to cleanup,
although ANALYZE/DISK/REPAIR handles it nicely.

--
David J Dachtera
dba DJE Systems
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