connect needs three arguments: connection string, user name, and password (at least that's how I understand the documentation). You're giving it only one argument.

If you want to store the username and password in the hash, too, use a hash of arrays: 

my %db_conn = (
    a_manager => [ 'DBI:Oracle:host=hostname1;sid=ABCDB01;port=1300', 
+'a_manager', 'a_manager' ],
    b_manager => [ 'DBI:Oracle:host=hostname1;sid=ABCDB01;port=1300', 
+'b_manager', 'b_manager' ],
    c_manager => [ 'DBI:Oracle:host=hostname1;sid=ABCDB01;port=1300', 
+'c_manager', 'c_manager' ],
    d_manager => [ 'DBI:Oracle:host=hostname1;sid=CBADB01;port=1300', 
+'d_manager', 'd_manager' ],
);

[download]

And dereference the value in the connection call: 

my $dbh = DBI->connect(@$data_source) or ...

[download]

Update: Added the example. 

($q=q:Sq=~/;[c](.)(.)/;chr(-||-|5+lengthSq)`"S|oS2"`map{chr |+ord
}map{substrSq`S_+|`|}3E|-|`7**2-3:)=~y+S|`+$1,++print+eval$q,q,a,

[download]

In reply to Re: Using a HASH to store a DBI connection by choroba
in thread Using a HASH to store a DBI connection by chris01010

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