perl - Can I use multiple keys in Berkeley DB? -

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i want use in berkeley db following perl logic (for many millions records):

$hash{key1}{key2}{key3}{count1}++; $hash{key1}{key2}{key3}{count2}++;  ...  (key1) {    (key2) {      (key3) {         print $hash{key1}{key2}{key3}{count1}."\t".$hash{key1}{key2}{key2}{count2};         }      }   }

any example multiple keys? may of couse use "pseudo-multiple" key ( key1_key2_key3 ); there other way?

berkeley-db doesn't support multiple keys that. each record can have 1 key.

you can concatenate keys form single key, stated.

you can use mldbm give appearance of nested keys. works storing serialized hash under key1, inefficient if have lot of keys nested under top-level key.

or, can give on bdb , go real sql database. dbd::sqlite easy install , includes sqlite database engine along driver.

i'd go either concatenating keys or real database, depending on you're trying do.


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