Number conversion to word in Bangla text in Oracle

/*Use the function to convert number to bangla text*/
CREATE OR REPLACE FUNCTION VALUE_IN_bangla(a_number NUMBER) RETURN CHAR IS
    TYPE numtab IS TABLE OF VARCHAR2(30)
    INDEX BY BINARY_INTEGER;
    number_chart numtab;
    num_value number;
    word_value varchar2(500);
    crore number;
    lac number;
    thou number;
    hund number;
    doubl number;
    sing number;
    deci number;
BEGIN
   --The number_chart Table

number_chart(1):= 'GK';
number_chart(2):= '`yB';
number_chart(3):= 'wZb';
number_chart(4):= 'Pvi';
number_chart(5):= 'cuvP';
number_chart(6):= 'Qq';
number_chart(7):= 'mvZ';
number_chart(8):= 'AvU';
number_chart(9):= 'bq';
number_chart(10):= '`k';
number_chart(11):= 'GMvi';
number_chart(12):= 'evi';
number_chart(13):= '‡Zi';
number_chart(14):= '‡PŠÏ';
number_chart(15):= 'c‡bi';
number_chart(16):= '‡lvj';
number_chart(17):= 'm‡Zi';
number_chart(18):= 'AvVv‡iv';
number_chart(19):= 'Ewbk';
number_chart(20):= 'wek';
number_chart(21):= 'GKzk';
number_chart(22):= 'evBk';
number_chart(23):= '‡ZBk';
number_chart(24):= 'PweŸk';
number_chart(25):= 'cuwPk';
number_chart(26):= 'QvweŸk';
number_chart(27):= 'mvZvk';
number_chart(28):= 'AvUvk';
number_chart(29):= 'EbwÎk';
number_chart(30):= 'wÎk';
number_chart(31):= 'GKwÎk';
number_chart(32):= 'GKwÎk';
number_chart(33):= '‡ZwÎk';
number_chart(34):= '‡PŠwÎk';
number_chart(35):= 'cuqwÎk';
number_chart(36):= 'QwÎk';
number_chart(37):= 'QwÎk';
number_chart(38):= 'AvUwÎk';
number_chart(39):= 'EbPwjøk';
number_chart(40):= 'Pwjøk';
number_chart(41):= 'GKPwjøk';
number_chart(42):= 'weqvwjøk';
number_chart(43):= '‡ZZvwjøk';
number_chart(44):= 'Pzqvwjøk    ';
number_chart(45):= 'cuqZvwjøk';
number_chart(46):= '†QPwjøk';
number_chart(47):= 'mvZPwjøk';
number_chart(48):= 'AvUPwjøk';
number_chart(49):= ' EbcÂvk';
number_chart(50):= 'cÂvk';
number_chart(51):= 'GKvbœ';
number_chart(52):= 'evqvbœ';
number_chart(53):= '‡Zàvbœ';
number_chart(54):= 'Pzqvbœ';
number_chart(55):= 'cÂvb';
number_chart(56):= 'Qv&àvbœ';
number_chart(57):= 'mvZvbœ';
number_chart(58):= 'AvUvbœ';
number_chart(59):= 'EblvU';
number_chart(60):= 'lvU';
number_chart(61):= 'GKlw&Æ';
number_chart(62):= 'evlw&Æ';
number_chart(63):= '†ZlwÆ';
number_chart(64):= '†PŠlwÆ';
number_chart(65):= 'cuqlwÆ';
number_chart(66):= '†QlwÆ';
number_chart(67):= 'mvZlwÆ';
number_chart(68):= 'AvUlwÆ';
number_chart(69):= 'EbmËi';
number_chart(70):= 'mËi';
number_chart(71):= 'GKvËi';
number_chart(72):= 'evnvËi';
number_chart(73):= 'wZqvËi';
number_chart(74):= 'PzqvËi';
number_chart(75):= 'cuPvËi';
number_chart(76):= 'wQqvËi';
number_chart(77):= 'mvZvËi';
number_chart(78):= 'AvUvËi';
number_chart(79):= 'EbAvwk';
number_chart(80):= 'Avwk';
number_chart(81):= 'GKvwk';
number_chart(82):= 'weivwk';
number_chart(83):= 'wZivwk';
number_chart(84):= 'Pzivwk';
number_chart(85):= 'cuPvwk';
number_chart(86):= 'wQqvwk';
number_chart(87):= 'mvZvwk';
number_chart(88):= 'AvUvwk';
number_chart(89):= 'EbbeŸB';
number_chart(90):= 'beŸB';
number_chart(91):= 'GKvbeŸB';
number_chart(92):= 'weivbeŸB';
number_chart(93):= 'wZivbeŸB';
number_chart(94):= 'PzivbeŸB';
number_chart(95):= 'cuPvbeŸB';
number_chart(96):= 'wQqvbeŸ&&&&&B';
number_chart(97):= 'mvZvbeŸB';
number_chart(98):= 'AvUvbeŸB';
number_chart(99):= 'wbivbeŸB';

    --Converting
    crore:=floor(a_number/10000000);
     lac:=floor((a_number-trunc(a_number,-7))/100000);
     thou:=floor((a_number-trunc(a_number,-5))/1000);
     hund:=floor((a_number-trunc(a_number,-3))/100);
     doubl:=trunc(a_number-trunc(a_number,-2),0);
--     sing:=trunc(a_number-trunc(a_number,-1),0);
     deci:=(a_number-trunc(a_number,0))*100;

    if crore<>0 then    --Crore conversion
        if crore between 100 and 999 then
          word_value:=number_chart(floor(crore/100))||' kZ '||number_chart(substr(crore,2))||' '||'†KvwU ';
        else
            word_value:=number_chart(crore)||' '||'†KvwU ';
        end if;
    end if;

    if lac <>0 then    --Lac conversion
    word_value:=word_value||number_chart(lac)||' '||'jÿ ';
    end if;

    if thou <>0 then    --Thousand conversion
         word_value:=word_value||number_chart(thou)||' '||'nvRvi ';
    end if;

    if hund <>0 then    --Hundred conversion
     word_value:=word_value||number_chart(hund)||' '||'kZ ';
    end if;

    if doubl <>0 then    --Double conversion
     word_value:=word_value||number_chart(doubl)||' ';
    end if;

    if deci <>0 then    --Decimal conversion
      word_value:=word_value||' '||number_chart(deci)||' '||'cqmv ';
    end if;
    return(lower(word_value));
END;
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