例如表product有如下数据:
pname pcount
面包 3
牛奶 4
需要查询出来的结果为:
pname
面包
面包
面包
牛奶
牛奶
牛奶
牛奶
------解决方案--------------------
----------------------------------------------------------------
-- Author :DBA_HuangZJ(發糞塗牆)
-- Date :2014-07-17 11:24:11
-- Version:
-- Microsoft SQL Server 2012 - 11.0.5058.0 (X64)
-- May 14 2014 18:34:29
-- Copyright (c) Microsoft Corporation
-- Enterprise Edition: Core-based Licensing (64-bit) on Windows NT 6.3 <X64> (Build 9600: ) (Hypervisor)
--
----------------------------------------------------------------
--> 测试数据:[product]
if object_id('[product]') is not null drop table [product]
go
create table [product]([pname] varchar(4),[pcount] int)
insert [product]
select '面包',3 union all
select '牛奶',4
--------------开始查询--------------------------
SELECT pname
FROM ( SELECT pname ,
REPLICATE(CAST(pcount AS VARCHAR(100)) + ',', pcount) pcount
FROM product
) a ,
master..spt_values
WHERE number >= 1
AND number <= LEN(pcount)
AND type = 'p'
AND SUBSTRING(',' + pcount, number, 1) = ','
----------------结果----------------------------
/*
pname
-----
面包
面包
面包
牛奶
牛奶
牛奶
牛奶
*/
------解决方案--------------------
WITH a1 (pname,pcount) AS
(
SELECT '面包',3 UNION ALL
SELECT '牛奶',4
)
SELECT a.pname
FROM a1 a
JOIN master.dbo.spt_values b ON b.number BETWEEN 1 AND a.pcount
WHERE b.Type='P'