SQL Expressions: Query Service Support (#101955)

---------

Co-authored-by: Adam Simpson <adam@adamsimpson.net>
Co-authored-by: Sarah Zinger <sarah.zinger@grafana.com>

pkg/expr/nodes.go

@@ -341,7 +341,7 @@ func executeDSNodesGrouped(ctx context.Context, now time.Time, vars mathexp.Vars
 				}
 
 				var result mathexp.Results
-				responseType, result, err := s.converter.Convert(ctx, dn.datasource.Type, dataFrames)
+				responseType, result, err := s.converter.Convert(ctx, dn.datasource.Type, dataFrames, dn.isInputToSQLExpr)
 				if err != nil {
 					result.Error = makeConversionError(dn.RefID(), err)
 				}
@@ -409,44 +409,9 @@ func (dn *DSNode) Execute(ctx context.Context, now time.Time, _ mathexp.Vars, s
 	}
 
 	var result mathexp.Results
-	// If the datasource node is an input to a SQL expression,
-	// the data must be in the Long format
-	if dn.isInputToSQLExpr {
-		var needsConversion bool
-		// Convert it if Multi:
-		if len(dataFrames) > 1 {
-			needsConversion = true
-		}
 
-		// Convert it if Wide (has labels):
-		if len(dataFrames) == 1 {
-			for _, field := range dataFrames[0].Fields {
-				if len(field.Labels) > 0 {
-					needsConversion = true
-					break
-				}
-			}
-		}
+	responseType, result, err = s.converter.Convert(ctx, dn.datasource.Type, dataFrames, dn.isInputToSQLExpr)
 
-		if needsConversion {
-			convertedFrames, err := ConvertToFullLong(dataFrames)
-			if err != nil {
-				return result, fmt.Errorf("failed to convert data frames to long format for sql: %w", err)
-			}
-			result.Values = mathexp.Values{
-				mathexp.TableData{Frame: convertedFrames[0]},
-			}
-			return result, nil
-		}
-
-		// Otherwise it is already Long format; return as is
-		result.Values = mathexp.Values{
-			mathexp.TableData{Frame: dataFrames[0]},
-		}
-		return result, nil
-	}
-
-	responseType, result, err = s.converter.Convert(ctx, dn.datasource.Type, dataFrames)
 	if err != nil {
 		err = makeConversionError(dn.refID, err)
 	}