佚名是译名 发表于 2016-6-2 10:07
选择C
D1 D2分别返回01-SEP-11 01-OCT-11,
V1 V2通过to_char返回的字符的长度都是九,September是九个字 ...
又是格式问题
SQL> select length(TO_CHAR( TO_DATE ('10/2011', 'MM/YYYY'),'Month')) from dual;
LENGTH(TO_CHAR(TO_DATE('10/2011','MM/YYYY'),'MONTH'))
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9
已用时间:00: 00: 00.00
SQL> select length(TO_CHAR( TO_DATE ('10/2011', 'MM/YYYY'),'fmMonth')) from dual;
LENGTH(TO_CHAR(TO_DATE('10/2011','MM/YYYY'),'FMMONTH'))
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7
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