What is a real example of what you represent with a hash?

Question

I'm just trying to figure out when you need to use a hash, and when it's better to use an array. What real world object will the hash represent, say, in the case of strings?

Answer 1

I believe that sometimes a hash is referred to as a “dictionary”, and I think this is a good example in itself. If you want to find the definition of a word, then it's nice to do something like:

definition['pernicious']

Instead of trying to figure out the correct numerical index to be stored in the file.

This answer assumes that with a "hash" you basically just reference an associative array.

Answer 2

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Answer 3

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Answer 4

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Answer 8

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Answer 9

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Answer 10

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Answer 11

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Answer 12

(php code)

$david        = new stdclass();
$david->name  = "david";
$david->age   = 12;
$david->id    = 1;
$david->title = "manager";

$joe        = new stdclass();
$joe->name  = "joe";
$joe->age   = 17;
$joe->id    = 2;
$joe->title = "employee";

// option 1: lets put users by index
$users[] = $david;
$users[] = $joe;

// option 2: lets put users by title
$users[$david->title] = $david;
$users[$joe->title]   = $joe;

Now the question is: who is the manager? Answer:

$users["manager"]