关于字符串缓冲区太小的问题，ORA-06502!在线等啊！

这是存储过程的部分代码；
V_SQL := 'CREATE GLOBAL TEMPORARY TABLE myTempTable
        (
  SERIAL_NO           VARCHAR2(18) not null,
  ACT_ID              VARCHAR2(18) not null,
  REGION_CODE         VARCHAR2(5) not null,
  GROUP_ID            VARCHAR2(14) not null,
  CHN_CODE            VARCHAR2(5) not null,
  ID_NO               VARCHAR2(20) not null,
  CUST_ID             VARCHAR2(20) not null,
  PHONE_NO            VARCHAR2(14) not null,
  MEANS_ID            VARCHAR2(18) not null,
  FEE_SUM             NUMBER(12,2),
  CASH_MONEY          NUMBER(12,2),
  ADD_PHONE_NO        VARCHAR2(14),
  SYS_PAY_TYPE        VARCHAR2(50),
  SYS_PAY_MONEY       NUMBER(12,2),
  PAY_TYPE_VALUE      VARCHAR2(50),
  GIFT_CODE           VARCHAR2(100),
  GIFT_NAME           VARCHAR2(500),
  CARD_TYPE           VARCHAR2(100),
  CARD_NUM            VARCHAR2(100),
  RESOURCE_BRAND      VARCHAR2(50),
  RESOURCE_MODEL      VARCHAR2(50),
  RESOURCE_COST_SUB   NUMBER(12,2),
  RESOURCE_COST_PRICE NUMBER(12,2),
  RESOURCE_FEE        NUMBER(12,2),
  PRI_FEE_CODE        VARCHAR2(50),
  PRI_FEE_NAME        VARCHAR2(100),
  DISTRI_FEE_CODE     VARCHAR2(50),
  DISTRI_FEE_NAME     VARCHAR2(100),
  ADD_FEE_CODE        VARCHAR2(500),
  ADD_FEE_NAME        VARCHAR2(1000),
  SP_CODE             VARCHAR2(500),
  SP_NAME             VARCHAR2(1000),
  SCORE               VARCHAR2(50),
  CONSUME_SCORE       VARCHAR2(50),
  CONSUME_VALUE       NUMBER(12,2),
  DATA_CARD_NO        VARCHAR2(50),
  OPER_ID             VARCHAR2(20),
  OPER_NAME           VARCHAR2(20),
  OPER_TIME           DATE,
  BAK1                VARCHAR2(255),
  BAK2                VARCHAR2(255),
  BAK3                VARCHAR2(255),
  OPER_TYPE           VARCHAR2(50),
  ORDER_ID            VARCHAR2(18),
  CASH_START_TIME     DATE,
  SYS_PAY_MONTH       VARCHAR2(50),
  SYS_PAY_PER         NUMBER(12,2),
  SYS_START_TIME      DATE,
  SYS_END_TIME        DATE,
  SYS_LIMIT_MONEY     NUMBER(12,2),
  IS_AWARD            VARCHAR2(5),
  GIFT_MODEL          VARCHAR2(5),
  CARD_IS_IRC         VARCHAR2(5),
  CARD_BEGIN_NO       VARCHAR2(50),
  CARD_END_NO         VARCHAR2(50),
  RESOURCE_IMEI_CODE  VARCHAR2(50),
  DELIVERY_TIME       DATE,
  QUALITY_LIMIT       VARCHAR2(10),
  BIZ_CODE            VARCHAR2(200),
  KX_CODE_BUNCH       VARCHAR2(500),
  PRI_FEE_VALID       VARCHAR2(5)
)
      ON COMMIT PRESERVE ROWS';
execute immediate V_SQL;
这是想建一个临时表，但是在测试的时候，在这行V_SQL := 'CREATE GLOBAL TEMPORARY TABLE myTempTable
报ora-06502 numeric or value error:character string buffer to small
请问要如何解决，我用的是PL/SQL DEVELOPER,谢谢了！