取出 sql表中第31到40的记录(以自动增长 ID为主键)
sql server 方案
1:
selecttop 10 * from t where id not in (select top 30 id from t order by id ) orde byid;
2:
selecttop 10 * from t where id in (select top 40 id from t order by id) order by iddesc;
mysql 方案:
select * from t order by idlimit 30,10;
oracle 方案:
select * from (select rownum r,* from t where r<=40) wherer>30;
分页技术(直接利用 sql 语句进行分页,效率最高和最推荐的)
mysql:
sql = "select * from articles limit " +(pageNo-1)*pageSize + "," + pageSize;
oracle:
sql = "select * from " +"(select rownum r,* from " + "(select* from articles order by postime desc)" +"where rownum<= " +pageNo*pageSize +") tmp " +"wherer>" +(pageNo-1)*pageSize;
sqlserver:
sql = "select top 10 * from id not id(select top" + (pageNo- 1)*pageSize + "id from articles)"