无限大
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MAXVALUE integer specifies the maximum value the sequence can generate. This integer value can have 28 or fewer digits.够大了吧
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MAXVALUE integer specifies the maximum value the sequence can generate. This integer value can have 28 or fewer digits.够大了吧
其实用循环序列后,可以在前加一个时间限制它,就可以唯一标识它。
select to_char(sysdate,'yyyymmdd')||lpad(id.nextval,6,'0') into id from table_name;