我想SQL查詢轉換爲LINQ查詢

Question

這是我的SQL查詢

SELECT a.CLASS_ID,a.ACTIVITY_TYPE_ID,COUNT(*) 
FROM AIS.CLASS_ASSESSMENT_DATE_INFO a 
WHERE a.CLASS_ID =22222 
GROUP by a.CLASS_ID,a.ACTIVITY_TYPE_ID 

我想這個查詢LINQ查詢轉換。你可以幫我嗎 ？

Answer 1

試試這個： -

var result = db.CLASS_ASSESSMENT_DATE_INFO.Where(x => x.CLASS_ID == 22222) 
       .GroupBy(x => new { x.CLASS_ID, x.ACTIVITY_TYPE_ID }) 
       .Select(x => new 
         { 
          CLASS_ID = x.Key.CLASS_ID, 
          ACTIVITY_TYPE_ID = x.Key.ACTIVITY_TYPE_ID, 
          Count = x.Count()   
         }); 

或在情況下，如果你喜歡query syntax： -

var result = from x in db.CLASS_ASSESSMENT_DATE_INFO 
      where x.CLASS_ID == 22222 
      group x by new { x.CLASS_ID, x.ACTIVITY_TYPE_ID } into g 
      select new 
         { 
          CLASS_ID = g.Key.CLASS_ID, 
          ACTIVITY_TYPE_ID = g.Key.ACTIVITY_TYPE_ID, 
          Count = g.Count()   
         }; 

Answer 2

var q = from a in AIS.CLASS_ASSESSMENT_DATE_INFO 
     where a.CLASS_ID == 22222 
     group a by new{ 
      a.CLASS_ID, 
      a.ACTIVITY_TYPE_ID} into g 
     select new{ 
      CLASS_ID = g.Key.CLASS_ID, 
      ACTIVITY_TYPE_ID = g.Key.ACTIVITY_TYPE_ID, 
      Count = g.Count() 
     };