SQL & PL/SQL

Hello everyone!

I have a problem about use clob in my function,when my function use clob in JSON_TABLE,the error message tells me"ORA-40484:invalid data type for JSON-TABLE column".

But when I use "SOLD_TYPE VARCHAR2(4000 BYTE) PATH '$.SOLD_TYPE'" here is no error message,why?

My function's code is ：

CREATE OR REPLACE 
function FN_ECOS_GETORDINFO(V_IN_JSON  IN  CLOB) return TP_ECOS_OP_TABLE pipelined as    
item TP_ECOS_OP_ROW; 
  
BEGIN    
for myrow in (
  SELECT * FROM JSON_TABLE(V_IN_JSON,'$'
  COLUMNS(
  SYSID VARCHAR2(50) PATH '$.SysUserInfo.SysId',
  NESTED PATH '$.DATA[*]'
  COLUMNS(
  H_ROW_ID VARCHAR2(50 BYTE) PATH '$.ROW_ID',
  H_ORDER_NO VARCHAR2(100 BYTE) PATH '$.ORDER_NO',
  H_MEMBER_NAME VARCHAR2(100 BYTE) PATH '$.MEMBER_NAME',
  H_CONSIGNEE VARCHAR2(100 BYTE) PATH '$.CONSIGNEE',
  H_CONSIGNEE_MOBILE VARCHAR2(100 BYTE) PATH '$.CONSIGNEE_MOBILE',
  H_SHOP_ID VARCHAR2(100 BYTE) PATH '$.SHOP_ID',
  H_SHOP_NAME VARCHAR2(100 BYTE) PATH '$.SHOP_NAME',
  H_CONSIGNEE_AREA VARCHAR2(100 BYTE) PATH '$.CONSIGNEE_AREA',
  H_CONSIGNEE_ADDR VARCHAR2(500 BYTE) PATH '$.CONSIGNEE_ADDR',
  H_GOODS_AMOUNT VARCHAR2(100 BYTE) PATH '$.GOODS_AMOUNT',
  NESTED PATH '$.ROWS[*]'
  COLUMNS(
  ROW_ID VARCHAR2(50 BYTE) PATH '$.ROW_ID',
  DETAIL_ORDER_NO VARCHAR2(100 BYTE) PATH '$.ORDER_NO',
  BN VARCHAR2(100 BYTE) PATH '$.BN',
  NAME VARCHAR2(200 BYTE) PATH '$.NAME',
  BARCODE VARCHAR2(100 BYTE) PATH '$.BARCODE',
  NUMS VARCHAR2(100 BYTE) PATH '$.NUMS',
  SALES_AMOUNT VARCHAR2(100 BYTE) PATH '$.SALES_AMOUNT',
  SOLD_TYPE_RETGOODS VARCHAR2(50 BYTE) PATH '$.SOLD_TYPE_RETGOODS'
  SOLD_TYPE_REFUND VARCHAR2(50 BYTE) PATH '$.SOLD_TYPE_REFUND',
  SOLD_TYPE_SUPAGAIN VARCHAR2(50 BYTE) PATH '$.SOLD_TYPE_SUPAGAIN',
  SOLD_TYPE VARCHAR2(4000 BYTE) PATH '$.SOLD_TYPE'
  /*when I change forward line to => 
  SOLD_TYPE CLOB PATH '$.SOLD_TYPE'
  the error message tells me "ORA-40484:invalid data type for JSON-TABLE column"
  But when I use "SOLD_TYPE VARCHAR2(4000 BYTE) PATH '$.SOLD_TYPE'" here is no error message,why?
  */
  )
  )
  )
  )
) loop    
  item := TP_ECOS_OP_ROW(
  myrow.SYSID,
  myrow.H_ROW_ID,
  myrow.H_ORDER_NO,
  myrow.H_MEMBER_NAME,
  myrow.H_CONSIGNEE,
  myrow.H_CONSIGNEE_MOBILE,
  myrow.H_SHOP_ID,
  myrow.H_SHOP_NAME,
  myrow.H_CONSIGNEE_AREA,
  myrow.H_CONSIGNEE_ADDR,
  myrow.H_GOODS_AMOUNT,
  myrow.ROW_ID,
  myrow.DETAIL_ORDER_NO,
  myrow.BN,
  myrow.NAME,
  myrow.BARCODE,
  myrow.NUMS,
  myrow.SALES_AMOUNT,
  myrow.SOLD_TYPE_RETGOODS,
  myrow.SOLD_TYPE_REFUND, 
  myrow.SOLD_TYPE_SUPAGAIN, 
  myrow.SOLD_TYPE
  );    
  pipe row (item);    
end loop;
END;