诚然，你是在把这两个值相加，但你应该使用的不是sum函数，而是字面上的 add values。

SQL> desc catalog
 Name                                      Null?    Type
 ----------------------------------------- -------- ----------------------------
 STUD_TYPE                                          VARCHAR2(15)
 STIPEND                                            NUMBER(3)
 COMPENSATION                                       NUMBER(4,2)
 TOTAL_PAID                                         NUMBER(5,2)

SQL>

控制文件-注意total_paid列的值：

LOAD DATA
INFILE *
REPLACE
INTO TABLE catalog
FIELDS TERMINATED BY ',' 
TRAILING NULLCOLS
(
stud_type,
stipend,
compensation,
total_paid ":stipend + :compensation"
)

begindata
Type A,50,10
Type B,20,-2

测试：

SQL> $sqlldr scott/tiger@orcl control=test47.ctl log=test47.log

SQL*Loader: Release 18.0.0.0.0 - Production on Pet Pro 23 07:56:01 2022
Version 18.5.0.0.0

Copyright (c) 1982, 2018, Oracle and/or its affiliates.  All rights reserved.

Path used:      Conventional
Commit point reached - logical record count 1
Commit point reached - logical record count 2

Table CATALOG:
  2 Rows successfully loaded.

Check the log file:
  test47.log
for more information about the load.

结果：

SQL> select * from catalog;

STUD_TYPE          STIPEND COMPENSATION TOTAL_PAID
--------------- ---------- ------------ ----------
Type A                  50           10         60
Type B                  20           -2         18

SQL>