08:15:02 SQL> select 0.5 from dual; 0.5
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.5已用时间: 00: 00: 00.10
08:19:49 SQL> col 0.5 format 0.0
08:19:58 SQL> select 0.5 from dual; 0.5
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0.5已用时间: 00: 00: 00.20
08:20:00 SQL> select to_char(0.5,'0.0') from dual;TO_C
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0.5已用时间: 00: 00: 00.00
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.5已用时间: 00: 00: 00.10
08:19:49 SQL> col 0.5 format 0.0
08:19:58 SQL> select 0.5 from dual; 0.5
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0.5已用时间: 00: 00: 00.20
08:20:00 SQL> select to_char(0.5,'0.0') from dual;TO_C
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0.5已用时间: 00: 00: 00.00
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0.5已选择 1 行。
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0.5Executed in 0 secondsSQL>
08:28:36 SQL> select 0.5 from dual; 0.5
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0.50已用时间: 00: 00: 00.00
08:28:45 SQL> set numformat 0.0
08:29:04 SQL> select 0.5 from dual
08:29:14 2 / 0.5
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0.5已用时间: 00: 00: 00.00
08:29:16 SQL>
如果是作为字符型,上面已经有了,to_char(0.5,'0.00')就行了……