如果ORACLE遇到非法或异常的时间类型数据时,在某些特定的情况下将其自动转换为rsquo;0000-00-00rsquo;而存储下来,不会抛出异
在一次datastage做etl,需要将一个source库的tab1数据导入到目标库tab2,两张表结构相同,发现etl执行报错invalid julian day
如果Oracle遇到非法或异常的时间类型数据时,在某些特定的情况下将其自动转换为’0000-00-00’而存储下来,不会抛出异常或错误提示。
比如在PL/SQL下,正常情况是不允许 年份为0值的:
SQL> select to_date('0000-01-01','yyyy-mm-dd') from dual;
select to_date('0000-01-01','yyyy-mm-dd') from dual
ORA-01841: (full) year must be between -4713 and +9999, and not be 0
但如果使用DATE函数,ORACLE将不会给出错误提示,而自动转换为‘0000-00-00‘:
SQL> select date '0000-01-01' from dual;
DATE'0000-01-01'
----------------
0/0/0000
这时如果使用DATE函数处理后来插入或更新这类日期值时,系统是不会给出错误提示,这在9i和10G下都是同样的处理方式。
还有另外两种情况,在PL/SQL下也会出现这样的问题:
1. 如果日期表达式的结果小于或等于0,结果都为'0000/00/00':
SQL> select to_date('0001-01-01', 'yyyy-mm-dd')-720 from dual;
TO_DATE('0001-01-01','YYYY-MM-
------------------------------
0/0/0000
SQL> select to_date('0001-01-01', 'yyyy-mm-dd')-365 from dual;
TO_DATE('0001-01-01','YYYY-MM-
------------------------------
0/0/0000
2. 对100到1500年之内的所有整百年的日期进行计算,如果结果为2月29的话,结果都为'0000/00/00':
SQL> select date '0099-2-28' +1 from dual;
DATE'0099-2-28'+1
-----------------
3/1/0099
SQL> select date '0100-2-28' +1 from dual;
DATE'0100-2-28'+1
-----------------
0/0/0000
在其它语言的处理上,也有类似的情况。而且在目前所有的ORACLE版本中,都没有对这类的错误修正,,所以在进行日期类型的值做转换和处理时,应该注意其转换后值的合法性和有效性。
后来处理还发现
有问题的日期用函数to_char的话会出现两种值,最后通过这两个值找到了问题数据,将错误日期改掉才解决~
to_char(DISABLE_DATE,'yyyy-MM-dd') = '3593-11-30'
or to_char(CLMDOC_READY_DATE,'yyyy-MM-dd') = '3593-11-30'
or to_char(DEATH_DATE,'yyyy-MM-dd') = '3593-11-30'
or to_char(DIAGNOSE_DATE,'yyyy-MM-dd') = '3593-11-30'
or to_char(DELAY_DATE,'yyyy-MM-dd') = '3593-11-30'
or to_char(FCD,'yyyy-MM-dd') = '3593-11-30'
or to_char(LCD,'yyyy-MM-dd') = '3593-11-30'
or
to_char(DISABLE_DATE,'yyyy-MM-dd') = '0000-00-00'
or to_char(CLMDOC_READY_DATE,'yyyy-MM-dd') = '0000-00-00'
or to_char(DEATH_DATE,'yyyy-MM-dd') = '0000-00-00'
or to_char(DIAGNOSE_DATE,'yyyy-MM-dd') = '0000-00-00'
or to_char(DELAY_DATE,'yyyy-MM-dd') = '0000-00-00'
or to_char(FCD,'yyyy-MM-dd') = '0000-00-00'
or to_char(LCD,'yyyy-MM-dd') = '0000-00-00'
)
;

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