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in reply to Re^3: Storing data into hashes
in thread Storing data into hashes

Hi, I have used print statement inside the while loop to print the content of data and also used Data::Dumper.The output is as follows 

data returned is HASH(0x4e9574) 
data returned is HASH(0x4e9598) 
data returned is HASH(0x4e958c) 
data returned is HASH(0x4e961c) 
data returned is HASH(0x4e95b0) 
data returned is HASH(0x4e955c) 
data returned is HASH(0x4e94fc) 
data returned is HASH(0x4e9568) 
data returned is HASH(0x4e95e0) 
data returned is HASH(0x4e96d0) 
data returned is HASH(0x22d410) 
data returned is HASH(0x4e94e4) 
data returned is HASH(0x22d350) 
data returned is HASH(0x4e9574) 
data returned is HASH(0x4e9598) 
data returned is HASH(0x4e958c) 
contents of hash is $VAR1 = {
          '' => undef,
          'foo' => 'bar'
        };

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The output of query in sql is as follows: 
SQL> select seq_nbr,data_record from usage_inq;

SEQ_NBR DATA_RECORD
------------------ -----
               200 10
               145 10
               205 10
               450 10
              2227 10
              2386 10
               202 10
               204 10
               144 10
               472 10
              1042 10

SEQ_NBR DATA_RECORD
------------------ -----
              1261 10
               203 10
               504 10
               201 10
               503 10
16 rows selected.

SQL>

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Re^5: Storing data into hashes
by roboticus (Chancellor) on Dec 31, 2012 at 10:37 UTC

    But you didn't use Data::Dumper, so we can't see what the hash reference contains. If you used it you might see something like:

    $VAR1={ COLUMN=>'value', COLUMN2=>'value2' }

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    So then you could see the names of the keys in your hash. As mentioned previously, you can't just do:

    print "Foo %hash\n";

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    and expect to get anything useful from it.

    ...roboticus

    When your only tool is a hammer, all problems look like your thumb.

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[d/l]
[select]
Re^5: Storing data into hashes
by cdarke (Prior) on Jan 02, 2013 at 06:23 UTC
    Looks to me that you are printing the hash after the loop, not in the loop. The hash gets recreated for each row, you need to inspect it inside the loop.
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