python - cx_Oracle 'ORA-01843: not a valid month' 带有 unicode 参数

Question

我有以下内容:(使用 ipython)

In [30]: con = cx_Oracle.connect('refill_test02/******@MYDB')

In [31]: cur = con.cursor()

In [32]: cur.execute("ALTER SESSION SET NLS_DATE_FORMAT = 'YYYY-MM-DD HH24:MI:SS' NLS_TIMESTAMP_FORMAT = 'YYYY-MM-DD HH24:MI:SS.FF'")

In [33]: cur.execute("select to_date(:0), to_timestamp(:1) from dual", ['2013-03-12', '2013-03-12 08:22:31.332144'])
Out[33]: <__builtin__.OracleCursor on <cx_Oracle.Connection to refill_test02@MYDB>>

In [34]: cur.fetchall()
Out[34]: 
[(datetime.datetime(2013, 3, 12, 0, 0),
  datetime.datetime(2013, 3, 12, 8, 22, 31, 332144))]

In [35]: cur.execute("select to_date(:0), to_timestamp(:1) from dual", [u'2013-03-12', '2013-03-12 08:22:31.332144'])
Out[35]: <__builtin__.OracleCursor on <cx_Oracle.Connection to refill_test02@MYDB>>

In [36]: cur.fetchall()
Out[36]: 
[(datetime.datetime(2013, 3, 12, 0, 0),
  datetime.datetime(2013, 3, 12, 8, 22, 31, 332144))]

In [37]: cur.execute("select to_date(:0), to_timestamp(:1) from dual", [u'2013-03-12', u'2013-03-12 08:22:31.332144'])
---------------------------------------------------------------------------
DatabaseError                             Traceback (most recent call last)
/home/xxxxx/<ipython-input-37-8af80e5fc40c> in <module>()
----> 1 cur.execute("select to_date(:0), to_timestamp(:1) from dual", [u'2013-03-12', u'2013-03-12 08:22:31.332144'])

DatabaseError: ORA-01843: not a valid month


In [38]: cur.execute("select to_date(:0), to_timestamp(:1) from dual", [u'2013-03-12', '2013-03-12 08:22:31.332144'])
---------------------------------------------------------------------------
DatabaseError                             Traceback (most recent call last)
/home/xxxx/<ipython-input-38-bc628f006aa3> in <module>()
----> 1 cur.execute("select to_date(:0), to_timestamp(:1) from dual", [u'2013-03-12', '2013-03-12 08:22:31.332144'])

DatabaseError: ORA-01843: not a valid month


In [39]: cur.execute("ALTER SESSION SET NLS_DATE_FORMAT = 'YYYY-MM-DD HH24:MI:SS' NLS_TIMESTAMP_FORMAT = 'YYYY-MM-DD HH24:MI:SS.FF'")

In [40]: cur.execute("select to_date(:0), to_timestamp(:1) from dual", [u'2013-03-12', '2013-03-12 08:22:31.332144'])
Out[40]: <__builtin__.OracleCursor on <cx_Oracle.Connection to refill_test02@MYDB>>

In [41]: cur.fetchall()
Out[41]: 
[(datetime.datetime(2013, 3, 12, 0, 0),
  datetime.datetime(2013, 3, 12, 8, 22, 31, 332144))]

出于某种原因，我不能将 unicode 字符串用于时间戳参数 (IN[37])，更奇怪的是，在我这样做之后，我需要重置 session NLS 格式，然后才能再次使用普通字符串。

我正在使用: Cx_Oracle 5.1.2 python 2.7.3 甲骨文 10.2.0.1.0

有什么想法吗？

感谢您花时间阅读本文。

Answer 1

这实际上是 Oracle 10.5.0.2 和 11.2.0.1 中的一个错误。

错误可以重现如下:

在 session 中设置 NLS_TIMESTAMP_FORMAT。

使用 unicode 数据运行任何隐式或显式 TO_DATE 转换。

接下来带有 unicode 数据的隐式或显式 TO_TIMESTAMP 将触发时间戳格式的内部重置。

所有连续的 TO_TIMESTAMP 都将失败，时间戳的 TO_CHAR 将产生无效输出。

下面是测试行为的代码:

ALTER SESSION SET NLS_TERRITORY = 'AMERICA';
ALTER SESSION SET NLS_DATE_FORMAT = 'YYYY-MM-DD HH24:MI:SS' NLS_TIMESTAMP_FORMAT = 'YYYY-MM-DD HH24:MI:SS.FF';

REM --- WORKS:
SELECT TO_TIMESTAMP('2013-06-24 18:15:10.312') FROM DUAL;

REM --- WORKS:
SELECT TO_DATE('2013-06-24 18:15:10') FROM DUAL;

REM --- WORKS:
SELECT TO_TIMESTAMP('2013-06-24 18:15:10.312') FROM DUAL;

REM --- WORKS:
SELECT TO_TIMESTAMP(x) FROM (SELECT CAST('2013-06-24 18:15:10.312' AS NVARCHAR2(30)) AS X FROM DUAL);

REM --- WORKS:
SELECT TO_DATE(x) FROM (SELECT CAST('2013-06-24 18:15:10' AS NVARCHAR2(30)) AS X FROM DUAL);

REM --- WORKS:
SELECT TO_TIMESTAMP('2013-06-24 18:15:10.312') FROM DUAL;

REM !!! FAILS!
SELECT TO_TIMESTAMP(x) FROM (SELECT CAST('2013-06-24 18:15:10.312' AS NVARCHAR2(30)) AS X FROM DUAL);

REM !!! FAILS!
SELECT TO_TIMESTAMP('2013-06-24 18:15:10.312') FROM DUAL;

REM --- WORKS:
SELECT TO_DATE('2013-06-24 18:15:10') FROM DUAL;