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Re: in_array performance in unsorted vs sorted array

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On 5/23/2012 2:20 AM, William Gill wrote:
> I am reading transaction records from files. Each record has an
> alphanumeric GUID but that record may be repeated in more than one file
> (because of overlapping samples). I don't want to process duplicate
> records, so I am considering a simple flat file to store the GUID's of
> previously processed records.
>
> To keep things simple I plan to use $done=file() to read the flat file,
> and a simple if in_array to see if the current GUID has already been
> processed, if not process the current record and add its GUID to $done.
>
> Does anyone know if sorting an array has any significant impact on
> in_array, or can I simply push push values into $done?
>
> Also is there a better way than foreach() write() to get $done back into
> the flat file?
>

Arrays in PHP are associative; their keys are handled as hash values. 
So I suspect it makes no difference on whether the array is sorted or not.

Also, what's wrong with foreach() write()?  That's how you get arrays 
back into a file.  Ensure you lock the file so that you don't have two 
scripts running against it at the same time.

But it sounds like you should be using a database.  That would solve a 
lot of your problems.

-- 
==================
Remove the "x" from my email address
Jerry Stuckle
JDS Computer Training Corp.
jstucklex@attglobal.net
==================

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in_array performance in unsorted vs sorted array William Gill <noreply@domain.invalid> - 2012-05-23 02:20 -0400
  Re: in_array performance in unsorted vs sorted array Jerry Stuckle <jstucklex@attglobal.net> - 2012-05-23 08:16 -0400
    Re: in_array performance in unsorted vs sorted array William Gill <noreply@domain.invalid> - 2012-05-23 10:57 -0400
      Re: in_array performance in unsorted vs sorted array William Gill <noreply@domain.invalid> - 2012-05-23 11:01 -0400
    Re: in_array performance in unsorted vs sorted array Thomas Mlynarczyk <thomas@mlynarczyk-webdesign.de> - 2012-05-24 22:20 +0200
  Re: in_array performance in unsorted vs sorted array Captain Paralytic <paul_lautman@yahoo.com> - 2012-05-23 02:36 -0700

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