SQL Server r2--uses the Digital secondary table (master: Spt_values) Implement a digital field to repeat the record display

Original: SQL Server r2--uses the Digital auxiliary table (master.. Spt_values) Implement a digital field to repeat the record display

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Nothing to say, despise those who disregard copyright random crawl Blog Small site webmaster, Christmas, I wish you see God.

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have never seen someone to use distinct to heavy, but have not heard who also want to generate duplicate data. Today we have opened my eyes.

On the code bar.

1 --by WLS
2 --20151224
3 --Network code risky copy and paste should be cautious
4  Usetempdb5 GO
6 
7 IF object_id(N't_testbywls'N'U') is  not NULL
8 DROP TABLEt_testbywls;9 CREATE TABLET_testbywls (IdINTEGER PRIMARY KEY, NameNVARCHAR( the), QtyINTEGER)
Ten GO
 One 
 A INSERT  intoT_testbywlsVALUES
 -(1,'Thbytwo',3),
 -(2,'wlsandwho',2)
 the GO
 - 
 - SELECT *  fromt_testbywls - GO
 + 
 - -------------------------------------------------------------------------------------------
 +  withTempqty A  as
 at (
 -     SELECT  Number  asNum fromMaster.. Spt_valuesWHEREType='P'
 - )
 - SELECTA.id,a.qty fromT_testbywls A Left JOINTempqty b onB.num>0  andB.num<=A.qty - GO

Step into the line of thought

1 -------------------------------------------------------------------------------------------
2 --step0
3 SELECT  Number  asNum fromMaster.. Spt_valuesWHEREType='P'
4 GO
5 --Step1
6  withTempqty7  as
8 (
9     SELECT  Number  asNum fromMaster.. Spt_valuesWHEREType='P'
Ten )
 One SELECTA.id,a.qty,b.num fromT_testbywls A Left JOINTempqty b on 1=1
 A --Step2
 -  withTempqty -  as
 the (
 -     SELECT  Number  asNum fromMaster.. Spt_valuesWHEREType='P'
 - )
 - SELECTA.id,a.qty,b.num fromT_testbywls A Left JOINTempqty b on 1=1  andB.num>0  andB.num<=A.qty + --Step3
 -  withTempqty +  as
 A (
 at     SELECT  Number  asNum fromMaster.. Spt_valuesWHEREType='P'
 - )
 - SELECTA.id,a.qty fromT_testbywls A Left JOINTempqty b onB.num>0  andB.num<=A.qty - GO

Execution results

Execution plan

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In line with the principle of business, I asked why the victim had such a wave (wéi) fee (bèi) (Lì) (shǐ), Low (bù) (Rén) rate (Dào), violation (pò) anti (Huài) (rì) of (Nèi) (wǎ) (Tiáo) (yuē) The requirements,

Here is the question and answer.

It appears to be a problem with software architecture design and won't comment.

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SQL Server r2--uses the Digital secondary table (master: Spt_values) Implement a digital field to repeat the record display