bash-4.2$ export DBI_TRACE=9
bash-4.2$ perl the-script.pl -db db1 -user dbuser -pass ***
    DBI 1.636-ithread default trace level set to 0x0/9 (pid 22036 pi 92a7008) at DBI.pm line 296 via GetDBHandle.pm line 48
    > DBI>connect(dbi:Oracle:db1, dbuser, ****, HASH(0x92aa668))
    > DBI>install_driver(Oracle) for linux perl=5.020003 pid=22036 ruid=1009 euid=1009
       install_driver: DBD::Oracle version 1.74 loaded from /prod/perl/lib/site_perl/5.20.3/i686-linux-thread-multi/DBD/Oracle.pm
    New 'DBI::dr' (for DBD::Oracle::dr, parent='', id=undef)
    dbih_setup_handle(DBI::dr=HASH(0xe8d8ec8)=>DBI::dr=HASH(0xe8d8f28), DBD::Oracle::dr, 0, Null!)
    dbih_make_com(Null!, 0, DBD::Oracle::dr, 104, 0) thr#92a7008
    dbih_setup_attrib(DBI::dr=HASH(0xe8d8f28), Err, Null!) SCALAR(0x9ffae30) (already defined)
    dbih_setup_attrib(DBI::dr=HASH(0xe8d8f28), State, Null!) SCALAR(0x9d2e410) (already defined)
    dbih_setup_attrib(DBI::dr=HASH(0xe8d8f28), Errstr, Null!) SCALAR(0x9ffae60) (already defined)
    dbih_setup_attrib(DBI::dr=HASH(0xe8d8f28), TraceLevel, Null!) 0 (already defined)
    dbih_setup_attrib(DBI::dr=HASH(0xe8d8f28), FetchHashKeyName, Null!) 'NAME' (already defined)
    >> STORE       DISPATCH (DBI::dr=HASH(0xe8d8ec8) rc1/1 @3 g2 ima41c pid#22036) at /prod/perl/lib/site_perl/5.20.3/i686-linux-thread-multi/DBD/Oracle.pm line 81 via  at /prod/Modules/GetDBHandle.pm line 129
    -> STORE in DBD::_::common for DBD::Oracle::dr (DBI::dr=HASH(0xe8d8ec8)~0xe8d8f28 'ShowErrorStatement' 1) thr#92a7008
    STORE DBI::dr=HASH(0xe8d8f28) 'ShowErrorStatement' => 1
    <- STORE= ( 1 ) [1 items] at /prod/perl/lib/site_perl/5.20.3/i686-linux-thread-multi/DBD/Oracle.pm line 81 via  at /prod/Modules/GetDBHandle.pm line 129
    <- install_driver= DBI::dr=HASH(0xe8d8ec8)
    >> connect     DISPATCH (DBI::dr=HASH(0xe8d8ec8) rc2/3 @5 g2 ima8001 pid#22036) at /prod/perl/lib/site_perl/5.20.3/i686-linux-thread-multi/DBI.pm line 684 via  at /prod/Modules/GetDBHandle.pm line 129
    -> connect for DBD::Oracle::dr (DBI::dr=HASH(0xe8d8ec8)~0xe8d8f28 'db1' 'dbuser' **** HASH(0x9cf5588)) thr#92a7008
    New 'DBI::db' (for DBD::Oracle::db, parent=DBI::dr=HASH(0xe8d8f28), id=undef)
    dbih_setup_handle(DBI::db=HASH(0xe8df1e8)=>DBI::db=HASH(0xe8df138), DBD::Oracle::db, 9d39c48, Null!)
    dbih_make_com(DBI::dr=HASH(0xe8d8f28), 92c9918, DBD::Oracle::db, 240, e8df168) thr#92a7008
    dbih_setup_attrib(DBI::db=HASH(0xe8df138), Err, DBI::dr=HASH(0xe8d8f28)) SCALAR(0x9d39e18) (already defined)
    dbih_setup_attrib(DBI::db=HASH(0xe8df138), State, DBI::dr=HASH(0xe8d8f28)) SCALAR(0x9d39e78) (already defined)
    dbih_setup_attrib(DBI::db=HASH(0xe8df138), Errstr, DBI::dr=HASH(0xe8d8f28)) SCALAR(0x9d39e48) (already defined)
    dbih_setup_attrib(DBI::db=HASH(0xe8df138), TraceLevel, DBI::dr=HASH(0xe8d8f28)) 0 (already defined)
    dbih_setup_attrib(DBI::db=HASH(0xe8df138), FetchHashKeyName, DBI::dr=HASH(0xe8d8f28)) 'NAME' (already defined)
    dbih_setup_attrib(DBI::db=HASH(0xe8df138), HandleSetErr, DBI::dr=HASH(0xe8d8f28)) undef (not defined)
    dbih_setup_attrib(DBI::db=HASH(0xe8df138), HandleError, DBI::dr=HASH(0xe8d8f28)) undef (not defined)
    dbih_setup_attrib(DBI::db=HASH(0xe8df138), Profile, DBI::dr=HASH(0xe8d8f28)) undef (not defined)
        OCIAttrSet(0,OCI_HTYPE_SESSION, f6d8bcd2,11,Attr=OCI_ATTR_DRIVER_NAME,0)=INVALID_HANDLE