[vb.net] DataTable Count / Sum / Distinct

'// 정렬 후 유일한 값 추출

Dim DA() As String = D.Select("", "testPaperNum ASC").CopyToDataTable.AsEnumerable().Select(Function(DR)
                                        Return DR.Field(Of Long)("testPaperNum").ToString
                                    End Function).Distinct().ToArray




'// 특정 조건 데이터 갯수

Count = D.Select(String.Format("[testPaperNum]='{0}' AND [Difficulty]='{1}' AND [correct]='{2}'", DA, DB, 0)).Length
 
또는
 
Count = D.Compute("count(testPaperNum)", String.Format("[testPaperNum]='{0}' AND [Difficulty]='{1}' AND [correct]='{2}'", DA, DB, 0))




'// 조건에 부합하는 합계
 
sum = Convert.ToInt32(getCellValue(D.Compute("SUM(Scored)", String.Format("[testPaperNum]='{0}' AND [Difficulty]='{1}' AND [correct]='{2}'", DA, DB, 0))))