【转】走向DBA[MSSQL篇] 针对大表 设计高效的存储过程【原理篇】 附最差性能sql语句进化过程客串

SELECT

TOP

500 a.KeyName

FROM

bug01 a

LEFT

JOIN

bug02 b

on

a.KeyName= b.KeyName

WHERE

(a.KeyName

not

in

(

select

distinct

b.KeyName

From

bug02))

ORDER

BY

a.KeyName

asc

CREATE

TABLE

#p

(

OrderID

varchar

(50),

primary

key

(OrderID)

);

SET

@temp_text =

'INSERT INTO #p'

+@KeyText

--PRINT @temp_text

EXEC

(@temp_text)

SET

@KeyText =

'SELECT OrderIDFROM #p'

--如果一级表关联的操作次数比较多那么可以访源表操作 以临时表取代物理表

SET

@SubKeyText =

'select 一级表_A_被关联键 From 一级表_A with(nolock) where 一级表_A_关联源表键 in ('

+ @KeyText+

')'

CREATE

TABLE

#q

(

OrderID

varchar

(50),

primary

key

(OrderID)

);

SET

@temp_text =

'INSERT INTO #q '

+@SubKeyText

EXEC

(@temp_text)

SET

@SubKeyText =

'SELECT OrderIDFROM #q'

--如果一级表关联的操作次数不多可以直接生成数据过滤池

SET

@SubKeyTextforA =

'select 一级表_B_被二级关联键 From 一级表_B with(nolock) where 一级表_B_关联源表键 in ('

+ @KeyText+

')'

SET

@SubKeyTextforB =

'select 一级表_C_被二级关联键 From 一级表_C with(nolock) where 一级表_C_关联源表键 in ('

+ @KeyText+

')'

--如果存在更多层操作在此处可以继续关联资源过滤池 Demo只做到三层

SET

@THKeyTextforA =

'select 二级表_A_被三级关联键 From 二级表_A with(nolock) where 二级表_A_关联一级表键 in ('

+ @SubKeyTextforA+

')'

--SET @THKeyTextforB ='select 二级表_B_被三级关联键 From 二级表_B with(nolock) where 二级表_B_关联一级表键 in (' + @SubKeyTextforBank+')'

--将错误的批次订单号入异常表

Insert

into

异常表(@ExTable)

SELECT

OrderID

FROM

#p

--@ExTable用来存放异常数据 如果当期批次出错 则将本次批次订单信息入库@ExTable下一批次则过滤这些数据再执行

SET

@KeyText =

'SELECT TOP '

+

CAST

(@SynSize

AS

VARCHAR

(10))+

' '

+@Base_Key+

' FROM +'

+@BaseTable+

'+ WHERE '

+@Base_Key+

' not in (select '

+@Base_Key+

' From '

+@ExTable+

') '

--一级 直接关联源表主键 或为二级被关联的主表

INSERT

INTO

#k

VALUES

(

'一级表_A'

,@Base_Key,@KeyText,

''

) 

--一级表_A

INSERT

INTO

#k

VALUES

(

'一级表_B'

,@Base_Key,@KeyText,

''

) 

--一级表_B

INSERT

INTO

#k

VALUES

(

'一级表_C'

,@Base_Key,@KeyText,

''

) 

--一级表_C

--二级 规则间接关联

--@SubKeyText相关

INSERT

INTO

#k

VALUES

(

'二级表_A'

,

'二级表_A_关联一级键'

,@SubKeyText,

''

) 

--二级表_A

INSERT

INTO

#k

VALUES

(

'二级表_B'

,

'二级表_B_关联一级键'

,@SubKeyText,

''

) 

--二级表_B

INSERT

INTO

#k

VALUES

(

'二级表_C'

,

'二级表_C_关联一级键'

,@SubKeyText,

''

) 

--二级表_C

--特殊处理

--自定义操作

INSERT

INTO

#k

VALUES

(

'特殊表'

,

'特殊表关联键'

,

'自定义数据过滤方式'

,

''

)  

--其他 自增列处理

--修改订单,及其取消修改订单状态历史表

INSERT

INTO

#k

VALUES

(

'自增表'

,@Base_Key,@KeyText,

'自定义字段'

)

DECLARE

CUR_ORDERHEDER

INSENSITIVE

CURSOR

FOR

SELECT

TableName,KeyName,temptext,colname

FROM

#k

OPEN

CUR_ORDERHEDER

FETCH

CUR_ORDERHEDER

INTO

@Cur_Table,@Cur_Key,@Cur_W,@Cur_K

WHILE @@FETCH_STATUS = 0

BEGIN

EXECUTE

P_Task_Sub_Synchronization

@OutParam  = @OutParam

OUT

, @OutMessage = @OutMessage

OUT

,

@KeyText =@Cur_W,@

Table

= @Cur_Table,@Extension=@Extension,@IsDelSource=@IsDelSource,@KeyName=@Cur_Key,@ColName=@Cur_K

--SET @OutMessage = @OutMessage+@OutMessage

--PRINT @OutMessage

IF @OutParam <> 0

BEGIN

SET

@OutMessage = @OutMessage + @Cur_Table +

'操作失败'

ROLLBACK

TRAN

--将错误的批次订单号入异常表

Insert

into

异常表(@ExTable)

SELECT

OrderID

FROM

#p

DROP

TABLE

#k

DROP

TABLE

#p

DROP

TABLE

#q

RETURN

END

FETCH

CUR_ORDERHEDER

INTO

@Cur_Table,@Cur_Key,@Cur_W,@Cur_K

END

ClOSE

CUR_ORDERHEDER

DEALLOCATE

CUR_ORDERHEDER