如何优化查询??
有一个视图useraa:
SELECT DATEADD([day], SIGN(DATEDIFF(d, dbo.personal1.u_lastlogintime, GETDATE())
/ 28) * 28, dbo.personal1.u_lastlogintime) AS b_lastlogintime,
dbo.personal1.u_web, dbo.personal1.u_regtime, b.fashion
FROM dbo.user_money b RIGHT OUTER JOIN
dbo.personal1 ON b.userid = dbo.personal1.u_name AND b.id =
(SELECT TOP 1 id
FROM dbo.user_money
WHERE (from_date < GETDATE()) AND (to_date > GETDATE()) AND (state = ' ') AND
((manner = '时间 ') OR
((manner = '点击 ') AND (balance > 0))) AND userid = b.userid
然后用查询:
select dbo.useraa.b_lastlogintime, dbo.useraa.u_college,
dbo.useraa.id, dbo.useraa.u_name, dbo.useraa.u_sex,
dbo.useraa.u_vocation1, dbo.useraa.u_vocation2,
dbo.useraa.u_lastlogintime from dbo.useraa LEFT OUTER JOIN
dbo.c_order ON dbo.useraa.fashion = dbo.c_order.set_user AND
dbo.c_order.c_search =0 and dbo.c_order.com_user= '个人 ' ORDER BY dbo.c_order.corder,convert(varchar(10),dbo.useraa. b_lastlogintime,120) DESC,dbo.useraa.u_update DESC
速度很慢,如何优化???
[解决办法]
--try:
select U.b_lastlogintime, U.u_college, U.id, U.u_name, U.u_sex, U.u_vocation1, U.u_vocation2, U.u_lastlogintime
from dbo.useraa as U LEFT OUTER JOIN
(Select corder from dbo.c_order where com_user= '个人 ' and c_search =0) as C
ON U.fashion = C.set_user
ORDER BY C.corder,convert(varchar(10),U. b_lastlogintime,120) DESC,U.u_update DESC
--try2:
select U.b_lastlogintime, U.u_college, U.id, U.u_name, U.u_sex, U.u_vocation1, U.u_vocation2, U.u_lastlogintime
from dbo.useraa as U LEFT OUTER JOIN
(Select corder from dbo.c_order where com_user= '个人 ' and c_search =0) as C
ON U.fashion = C.set_user
ORDER BY C.corder, U. b_lastlogintime DESC, U.u_update DESC
[解决办法]
这么快!!
[解决办法]
自悟,呵呵
――――――――――――――――――――――――分页与分次取出
--页码i=2
--页数j=4
declare @c int
set @c = (select count(*) from tablea)
declare @a int
declare @b int
set @a = 1
set @b = @c/4--想分的页数
set @a = @b+1--该页首条
set @b = @b*2--页码--该页未条
declare @sql varchar(1000)
set @sql= 'select top ' + rtrim(@b-@a+1) + ' * from tablea where ID not in (select top '+ rtrim(@a-1)+ ' ID from tablea) '
exec(@sql)
[解决办法]
select a.b_lastlogintime, a.u_college,
a.id, a.u_name, a.u_sex,
a.u_vocation1, a.u_vocation2,
a.u_lastlogintime
from dbo.useraa a LEFT OUTER JOIN dbo.c_order b
ON a.fashion = b.set_user AND b.c_search =0 and b.com_user= '个人 '
ORDER BY b.corder,convert(varchar(10),a.b_lastlogintime,120) DESC,a.u_update DESC
[解决办法]
--TOP n 实现的通用分页存储过程(转)
CREATE PROC sp_PageView
@tbname sysname, --要分页显示的表名
@FieldKey nvarchar(1000), --用于定位记录的主键(惟一键)字段,可以是逗号分隔的多个字段
@PageCurrent int=1, --要显示的页码
@PageSize int=10, --每页的大小(记录数)
@FieldShow nvarchar(1000)= ' ', --以逗号分隔的要显示的字段列表,如果不指定,则显示所有字段
@FieldOrder nvarchar(1000)= ' ', --以逗号分隔的排序字段列表,可以指定在字段后面指定DESC/ASC
用于指定排序顺序
@Where nvarchar(1000)= ' ', --查询条件
@PageCount int OUTPUT --总页数
AS
SET NOCOUNT ON
--检查对象是否有效
IF OBJECT_ID(@tbname) IS NULL
BEGIN
RAISERROR(N '对象 "%s "不存在 ',1,16,@tbname)
RETURN
END
IF OBJECTPROPERTY(OBJECT_ID(@tbname),N 'IsTable ')=0
AND OBJECTPROPERTY(OBJECT_ID(@tbname),N 'IsView ')=0
AND OBJECTPROPERTY(OBJECT_ID(@tbname),N 'IsTableFunction ')=0
BEGIN
RAISERROR(N ' "%s "不是表、视图或者表值函数 ',1,16,@tbname)
RETURN
END
--分页字段检查
IF ISNULL(@FieldKey,N ' ')= ' '
BEGIN
RAISERROR(N '分页处理需要主键(或者惟一键) ',1,16)
RETURN
END
--其他参数检查及规范
IF ISNULL(@PageCurrent,0) <1 SET @PageCurrent=1
IF ISNULL(@PageSize,0) <1 SET @PageSize=10
IF ISNULL(@FieldShow,N ' ')=N ' ' SET @FieldShow=N '* '
IF ISNULL(@FieldOrder,N ' ')=N ' '
SET @FieldOrder=N ' '
ELSE
SET @FieldOrder=N 'ORDER BY '+LTRIM(@FieldOrder)
IF ISNULL(@Where,N ' ')=N ' '
SET @Where=N ' '
ELSE
SET @Where=N 'WHERE ( '+@Where+N ') '
--如果@PageCount为NULL值,则计算总页数(这样设计可以只在第一次计算总页数,以后调用时,把总页数传回给存储过程,避免再次计算总页数,对于不想计算总页数的处理而言,可以给@PageCount赋值)
IF @PageCount IS NULL
BEGIN
DECLARE @sql nvarchar(4000)
SET @sql=N 'SELECT @PageCount=COUNT(*) '
+N ' FROM '+@tbname
+N ' '+@Where
EXEC sp_executesql @sql,N '@PageCount int OUTPUT ',@PageCount OUTPUT
SET @PageCount=(@PageCount+@PageSize-1)/@PageSize
END
--计算分页显示的TOPN值
DECLARE @TopN varchar(20),@TopN1 varchar(20)
SELECT @TopN=@PageSize,
@TopN1=(@PageCurrent-1)*@PageSize
--第一页直接显示
IF @PageCurrent=1
EXEC(N 'SELECT TOP '+@TopN
+N ' '+@FieldShow
+N ' FROM '+@tbname
+N ' '+@Where
+N ' '+@FieldOrder)
ELSE
BEGIN
--处理别名
IF @FieldShow=N '* '
SET @FieldShow=N 'a.* '
--生成主键(惟一键)处理条件
DECLARE @Where1 nvarchar(4000),@Where2 nvarchar(4000),
@s nvarchar(1000),@Field sysname
SELECT @Where1=N ' ',@Where2=N ' ',@s=@FieldKey
WHILE CHARINDEX(N ', ',@s)> 0
SELECT @Field=LEFT(@s,CHARINDEX(N ', ',@s)-1),
@s=STUFF(@s,1,CHARINDEX(N ', ',@s),N ' '),
@Where1=@Where1+N ' AND a. '+@Field+N '=b. '+@Field,
@Where2=@Where2+N ' AND b. '+@Field+N ' IS NULL ',
@Where=REPLACE(@Where,@Field,N 'a. '+@Field),
@FieldOrder=REPLACE(@FieldOrder,@Field,N 'a. '+@Field),
@FieldShow=REPLACE(@FieldShow,@Field,N 'a. '+@Field)
SELECT @Where=REPLACE(@Where,@s,N 'a. '+@s),
@FieldOrder=REPLACE(@FieldOrder,@s,N 'a. '+@s),
@FieldShow=REPLACE(@FieldShow,@s,N 'a. '+@s),
@Where1=STUFF(@Where1+N ' AND a. '+@s+N '=b. '+@s,1,5,N ' '),
@Where2=CASE
WHEN @Where= ' ' THEN N 'WHERE ( '
ELSE @Where+N ' AND ( '
END+N 'b. '+@s+N ' IS NULL '+@Where2+N ') '
--执行查询
EXEC(N 'SELECT TOP '+@TopN
+N ' '+@FieldShow
+N ' FROM '+@tbname
+N ' a LEFT JOIN(SELECT TOP '+@TopN1
+N ' '+@FieldKey
+N ' FROM '+@tbname
+N ' a '+@Where
+N ' '+@FieldOrder
+N ')b ON '+@Where1
+N ' '+@Where2
+N ' '+@FieldOrder)
END
[解决办法]
自悟?那接分
[解决办法]
用存储过程实现速度一定快:
把视图生成临时表,在临时表的字列建索引。。
然后再执行
查询