[asterisk-users] Can someone give a plain english explanation of the HASH function?

[Alex Balashov]

There is no "plain English" explanation that is not made with reference 
to the concept of a hash, which is an algorithmic and programmatic 
technique.  The HASH() function is designed for people that understand 
what hashing is and need to make use of it.

So, the answer is, "it provides a hashing mechanism to the user."

The simplest way to discover what hashing is would be to educate 
yourself about hash tables and associative arrays (which provide 
high-level, usually type-safe syntactical bindings around the use of 
hash tables) in other contexts, after which it should be clear. 
Soliciting any sort of Asterisk-specific explanation is going to give 
you an incomplete, oversimplified, and/or reductionist viewpoint.

I would start here:

   http://en.wikipedia.org/wiki/Hash_function

Cheers,

-- Alex


Eric Chamberlain wrote:

> Can someone explain what the HASH function does and how to use it?
> 
> 
>    -= Info about function 'HASH' =-
> 
> [Syntax]
> HASH(hashname[,hashkey])
> 
> [Synopsis]
> Implementation of a dialplan associative array
> 
> [Description]
> In two argument mode, gets and sets values to corresponding keys  
> within a named
> associative array.  The single-argument mode will only work when  
> assigned to from
> a function defined by func_odbc.so.

-- 
Alex Balashov
Evariste Systems
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