不可思议的sql问题！！！！！

Question

UPDATE bcn_cus_address_end SET 
install_addr1=address1,
install_addr2=address2,
install_addr3=address3,
install_addr4=address4,
install_build_code=build_code,
install_addr_code=addr_code,
install_floor=Floor
WHERE
install_addr1 IS null 
AND Length(Nvl(address1,' '))<=40
AND Length(Nvl(address2,' '))<=40
AND Length(Nvl(address3,' '))<=80
AND Length(Nvl(address4,' '))<=160运行结果：
ORA-12899: value too large for column "INC"."BCN_CUS_ADDRESS_END"."INSTALL_ADDR2" (actual: 45, maximum: 40)
                                                                          
SELECT Length(address2) FROM bcn_cus_address_end WHERE Length(address2)>40
运行结果：
LENGTH(ADDRESS2)
              57
              41
              44
              50
              57
              43请问，为何update的时候出错？？？？？？？

Answer 1

可能跟字段类型有关，把install_addr2类型定义发出来看看，length()返回以字符为单位的长度

Answer 2

isntall_addr2  varchar2(40)

Answer 3

公司上不了Q呢。我也觉得很奇怪，怎么老是报错，难道AND Length(Nvl(address2,' '))<=40
失效了么？另外，不加NVL是可以update的。但是address1或address2或address3或address4为null的话就update不了了。