空表插入数据：一些字段从加一张表中取得

??????????????????? 一些字段直接插入值

??? insert into tableName

??????????????select studentCode,studentName,???????????????????? ?//另一表中字段

?????????????????????????'01','本表中字段赋值',32,???????????????????????????? ?//给本表中字段赋值

???????????????????????? to_date('substr(IdCode,7,15)','yy-MM-dd'),?//根据另一表中字段内容插入值：出生日期

???????????????????????? case when mod(substr(IdCode,17),2)=0 then '0' else '1' end, //case when 用法

???????????????????????? to_number(enterYear)+2,???????//char型转成数值型

?????????????? from anotherTable a

???????????????where not exists(select 1 from student st where st.studentCode=a.studentCode));? //去重复

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Java：db:创建数据库连接

????? String sql = "select * from tableName";

????? String insertSql = "insert into tableName......";

????? ResultSet rs = db.executeQuery(sql);?????? //查询结果

????? int row = db.exectueUpdate(insertSql);??????? //更新(条数)

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只取日期年份、月份、日：

????? String year=to_char(stu.date,'yyyy');

????? String month=to_char(stu.date,'MM');

????? String day=to_char(stu.date,'dd);

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表中记录去除重复

????? select distinct coborrowerCode from historyInfo; //查询时去除重复

????? delete from coborrower c where c.rowid != (

???????????????? select max(b.rowid) from coborrower b?
???????????????????????????where c.coborrowerCode = b.coborrowerCode); //删除重复记录

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