sql 分页技术

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分页语句

sqlserver 方案1: select top 10 * from t where id not in(select top 30 id from t order by id) order by id

方案2: select top 10 * from t where id in (select top 40 id from t order by id)oder by id desc

mysql: select * from t order by id limit 30,10

oracle: select * from (select rownum r * from t where r<=40)where r>30

 

分页技术:

mysql: sql ="select * from articles limit" +(pageNo-1)*pageSize + "," +pageSize;

 

 oracle: sql="select * from (select rownum r,* from(select * from articles order by posttime desc)where rownum <= " +pageNo *pageSize")tmp where r>" +(pageNo-1)*pageSize"; 

sqlserver:sql = "select top 10 * from id not id(select top " + (pageNo-1)*pageSize + "id from articles)"

 DataSource ds = new InitialContext().lookup(jndiurl); Connection cn = ds.getConnection(); //"select * from user where id=?" --->binary directive PreparedStatement pstmt = cn.prepareSatement(sql); ResultSet rs = pstmt.executeQuery() while(rs.next()) { out.println(rs.getString(1)); }

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也有观点认为(仔细对比体会):

1.Oracle:
select * from ( select row_.*, rownum rownum_ from ( query_SQL ) row_ where rownum =< max) where rownum_ >= min
2.SQL Server:
select top @pagesize * from tablename where id not in (select top @pagesize*(@page-1) id from tablename order by id) order by id

3.MySQL
select * from tablename limit position, counter

4.DB2
select * from (select *,rownumber() as ROW_NEXT from tablename) where ROW_NEXT between min and max

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1.分页方案一:(利用Not In和SELECT TOP分页)效率次之
语句形式:
SELECT TOP 10 * FROM TestTable
WHERE(ID NOT IN (SELECT TOP 20  id FROM  TestTable  ORDERBY  id))   ORDERBYID
SELECT  TOP 页大小 * FROM TestTable
WHERE( ID NOT IN (SELECT  TOP  每页大小-1*待查询页数-1  id  FROM  表 ORDERBY  id)) ORDERBYID
思路:先查询出待查询页之前的全部条数的id,查询ID不在这些ID中的指定数量条数

2.分页方案二:(利用ID大于多少和SELECT TOP分页)效率最高
语句形式:
SELECT  TOP  10 *   FROM  TestTable
WHERE(ID>(SELECT MAX(id) FROM(SELECT TOP20 id  FROM  TestTable ORDERBYid)AS T))ORDERBY ID
SELECT  TOP  页大小* FROM  TestTable
WHERE(ID>(SELECT MAX(id) FROM(SELECT TOP 每页大小*待查询页数-1  id FROM 表  ORDERBY id)AS T)) ORDERBY ID
思路:先获得待查询页的之前全部条数id,获得它们当中最大的ID号,以此最大ID号为标志,查找比这个ID号大的指定条数

3.分页方案三:
SELECT TOP PageSize * FROM(SELECT TOP nPage*PageSize * from YOURTABLE order by id)as a order by id desc
SELECT TOP 每页条数 * FROM (SELECT TOP 待查询页*每页条数) * from YOURTABLE order by id)as a order by id desc
思路:先正排序查询出待查询页之前(包括当前页)的全部条数,然后将其倒排序,取指定条数