语法
- group by 必须要和聚合函数一起用，否则语法不过
- select column1,count(1) from DATA_TABLE_SQL group by column1;
- 分页 用rownum
- select * from DATA_TABLE_SQL where rownum <= 100;
- select * from DATA_TABLE_SQL where rownum<=100 minus select * from DATAT_ABLE_SQL where rownum<=50;
- select * from (select t.*,rownum num from DATA_TABLE_SQL t where rownum<=100 ) where num>50;
- 日期
- 字符串转日期
- to_date(‘2018-08-23 00:00:00’,’yyyy-mm-dd hh24:mi:ss’)
- 字符串转日期