Duplicated col not allowed and datetimewithzone added (#1527)

Author: prithvi081099

gateway/modules/schema/helpers/helpers.go

@@ -525,7 +525,9 @@ func getCollectionSchema(doc *ast.Document, dbName, collectionName string) (mode
 					fieldTypeStuct.TypeIDSize = model.DefaultCharacterSize
 				}
 			}
-
+			if _, ok := fieldMap[field.Name.Value]; ok {
+				return nil, helpers.Logger.LogError(helpers.GetRequestID(context.TODO()), fmt.Sprintf("Column (%s) already exists in the Collection/Table(%s). Duplicate column not allowed", field.Name.Value, collectionName), nil, nil)
+			}
 			fieldMap[field.Name.Value] = &fieldTypeStuct
 		}
 	}

gateway/modules/schema/inspection.go

@@ -108,7 +108,7 @@ func generateInspection(dbType, col string, fields []model.InspectorFieldType, i
 
 			// add string between quotes
 			switch fieldDetails.Kind {
-			case model.TypeString, model.TypeVarChar, model.TypeChar, model.TypeID, model.TypeDateTime, model.TypeDate, model.TypeTime:
+			case model.TypeString, model.TypeVarChar, model.TypeChar, model.TypeID, model.TypeDateTime, model.TypeDate, model.TypeTime, model.TypeDateTimeWithZone:
 				field.FieldDefault = fmt.Sprintf("\"%s\"", field.FieldDefault)
 			case model.TypeJSON:
 				data, err := json.Marshal(field.FieldDefault)