[英]How can I achieve SQL Pivot statement from LINQ
我希望從LINQ實現下面的SQL語句。 我不確定是否可能? 有人可以給我建議嗎?
SELECT *
FROM (
SELECT CONVERT(VARCHAR, (DATEADD(WEEK, DATEDIFF(WEEK, 0, S.SampleDrawn), 0)), 101) [Date], [Range] =
CASE
WHEN ProbBacteremia >= 0 AND ProbBacteremia < 0.50 THEN 'Low'
WHEN ProbBacteremia >= 0.50 AND ProbBacteremia < 0.75 THEN 'Med'
ELSE 'High'
END
FROM Result.Calculation C INNER JOIN Data.SampleSet S ON C.SampleSetID = S.ID WHERE S.SampleDrawn >= DATEADD(WEEK,-1,GETDATE())) o
PIVOT
(
COUNT(o.[Range])
FOR [Range] IN (
[Low], [Med], [High])
) pt
ORDER BY [Date]
以上查詢的結果如下
Date Low Med High 09/04/2017 370 174 175 09/11/2017 764 352 389 09/18/2017 759 384 360 09/25/2017 765 385 404 10/02/2017 115 48 56
請注意,以上日期已按周分組。 就是 09/04,09/11,09/18等。我做了很多研究,但發現只按周數分組。
這是我所能想到的LINQ,它將返回以下結果集。
data = (from a in context.Calculations
where a.SampleSet.SampleDrawn >= dtStart && (isDeptFilter || a.SampleSet.Department == location)
group a by new { Text = RangeProvider(a.ProbBacteremia * 100, riskCats), Date = a.SampleSet.SampleDrawn.Date } into groupedData
orderby groupedData.Key.Date ascending
select new { Value = groupedData.Count(), Text = groupedData.Key.Text, Date = groupedData.Key.Date.ToShortDateString() }).ToList();
public static string RangeProvider(int value)
{
if (value > 0 && value <= 25)
{ return "Low"; }
if (value > 25 && value <= 75)
{ return "Medium"; }
if (value > 75 && value <= 90)
{ return "High"; }
else
{ return "Very High"; }
}
觀察者LINQ的結果數據集為
Date Text Value 09/04/2017 Low 65 09/04/2017 Med 80 09/04/2017 High 40 09/05/2017 Low 30 10/05/2017 Med 50 10/05/2017 High 44
希望這能解釋我要達到的目標。 請有人可以幫我嗎?
作為一種變通辦法,我使用了Entity Framework Core的“ FromSQL ”方法來執行我的存儲過程,該過程將處理所有GROUP BY。
你可以用這個
data = (from a in context.Calculations
where a.SampleSet.SampleDrawn >= dtStart && (isDeptFilter || a.SampleSet.Department == location)
group a by new { Text = RangeProvider(a.ProbBacteremia * 100, riskCats), Date = a.SampleSet.SampleDrawn.Date } into groupedData
orderby groupedData.Key.Date ascending
select new {
Date = groupedData.Key.Date.ToShortDateString() ,
Low = ( groupedData.Key.Text =="Low" )?groupedData.Count() : 0,
Medium = ( groupedData.Key.Text =="Medium" )?groupedData.Count() : 0,
High = ( groupedData.Key.Text =="High" )?groupedData.Count() : 0,
VeryHigh = ( groupedData.Key.Text =="Very High" )?groupedData.Count() : 0
}).ToList();
聲明:本站的技術帖子網頁,遵循CC BY-SA 4.0協議,如果您需要轉載,請注明本站網址或者原文地址。任何問題請咨詢:yoyou2525@163.com.