[asterisk-users] HASH, HASHKEYS, ClearHash explanation

[Pavel Jezek]

Tilghman Lesher wrote:
> On Sunday 27 July 2008 13:28:00 Pavel Jezek wrote:
>   
>> Hi, can somebody explain how to use this func/apps in asterisk?
>> I tried to find some examples on mailinglists or wiki, however without
>> success. thanks
>>     
>
> The primary intended use is in conjunction with func_odbc, to allow you to
> retrieve multiple values and reference them without having to assign each
> field to an individual variable.  Think 'SELECT *' where the fields included
> might change over time, and you don't want the placement of a minor field
> to completely break your dialplan.
>   
thanks, can you give some example, if this functions can be used with 
normal strings?
I found some example from bugreport 0008965, but I'm lost, what it's 
actually doing ...
exten => s,n,Set(HASH(access_control)=${ACCESS_CONTROL_DATA(${USER_ID})})