各种常见数据库分页实现（转）

因为数据量过大，如果一次性查询会耗用大量时间以及性能，因此对数据进行分页显示变得尤为重要，以下就列出一些常用数据库的sql分页实现。 

1.MySQL实现分页 
MySQL实现分页效果比较简单，只有一个limit关键字就可以解决。 

示例：SELECT username,password FROM tb_user WHERE id = 1 LIMIT 100,10; 
具体：select * from tableName where 条件 limit 当前页码*页面容量-1,页面容量 

2.Oralce实现分页 

SELECT * 
  FROM (SELECT A.*, ROWNUM RN FROM (SELECT * FROM tableName order by id) A WHERE ROWNUM <=20) 
WHERE RN >= 11; 

select count(*) from tableName where 条件 


3.Sqlserver实现分页 

sqlserver由于版本的不同，分页的实现方式也各不相同。 

SQL 2000 用临时表解决，通过在临时表中增加自增列解决RowNumber。 
DECLARE @Start INT 
DECLARE @End INT 
SELECT @Start = 14000,@End = 14050 

CREATE TABLE #employees (RowNumber INT IDENTITY(1,1), 
LastName VARCHAR(100),FirstName VARCHAR(100), 
EmailAddress VARCHAR(100)) 

INSERT INTO #employees (LastName, FirstName, EmailAddress) 
SELECT LastName, FirstName, EmailAddress 
FROM Employee 
ORDER BY LastName, FirstName, EmailAddress 
SELECT LastName, FirstName, EmailAddress 
FROM #employees 
WHERE RowNumber > @Start AND RowNumber <= @End 

DROP TABLE #employees 

GO　　 

SQL 2005/2008 由于支持了Row_Number于是通过派生表的方式解决（两个嵌套） 
DECLARE @Start INT 
DECLARE @End INT 
SELECT @Start = 14000,@End = 14050 

SELECT LastName, FirstName, EmailAddress 
FROM (SELECT LastName, FirstName, EmailAddress, 
ROW_NUMBER() OVER (ORDER BY LastName, FirstName, EmailAddress) AS RowNumber 
FROM Employee) EmployeePage 
WHERE RowNumber > @Start AND RowNumber <= @End 
ORDER BY LastName, FirstName, EmailAddress 
GO 
　　 

SQL 2005/2008 或者用CTE的方式实现，和派生表一样，就是好看点，执行计划都一样。 
DECLARE @Start INT 
DECLARE @End INT 
SELECT @Start = 14000,@End = 14050; 
WITH EmployeePage AS 
(SELECT LastName, FirstName, EmailAddress, 
ROW_NUMBER() OVER (ORDER BY LastName, FirstName, EmailAddress) AS RowNumber 
FROM Employee) 
SELECT LastName, FirstName, EmailAddress 
FROM EmployeePage 
WHERE RowNumber > @Start AND RowNumber <= @End 
ORDER BY LastName, FirstName, EmailAddress 
GO 
　　 
SQL SERVER 2012 比较给力支持了OFFSET，于是一个Select结束战斗,另外在2012里，如果前面加上TOP（50），那么执行计划就会少读很多行数据（读的精准了），提高性能。 
SELECT top(50) LastName, FirstName, EmailAddress 
FROM Employee 
ORDER BY LastName, FirstName, EmailAddress 
OFFSET 14000 ROWS 
FETCH NEXT 50 ROWS ONLY; 

4.DB2实现分页 
Db2实现分页与SQL Server类似, 但是可以不对资料排序(起始位置从1开始) 

对资料排序 
select * from ( 
    select t.*, ROW_NUMBER() OVER(ORDER BY CARD_ID asc) AS ROWNUM from CARD t ) a 
where ROWNUM > 20 and ROWNUM <=30 

不对资料排序 
select * from ( 
    select t.*, ROW_NUMBER() OVER() AS ROWNUM from CARD t ) a 
where ROWNUM > 20 and ROWNUM <=30 


以上为各种常见数据库分页语句，留存备用。

http://lafecat.iteye.com/blog/2186265