Synapse polybase data ingestion is not working - azure-synapse

Question

I have a task to convert the jobs from synapse bulk insert to synapse polybase pattern. As part of that I see that it doesn't work straight away. It is complaining about some datatypes etc as below.... where as there is no double datatypes sometimes in the source query. Please help to understand if there a basic pattern or casting we need to do before we use polybase.
Here the source SQL I used
SELECT TOP (1000) cast([SiteCode_SourceId] as varchar(1000))
[SiteCode_SourceId]
,cast([EquipmentCode_SourceId] as varchar(1000))
[EquipmentCode_SourceId]
,FORMAT([RecordedAt],'yyyy-MM-dd HH:mm:ss.fffffff') AS
[RecordedAt]
,cast([DataLineage_SK] as varchar(1000)) [DataLineage_SK]
,cast([DataQuality_SK] AS varchar(1000)) [DataQuality_SK]
,cast([FixedPlantAsset_SK] as varchar(1000))
[FixedPlantAsset_SK]
,cast([ProductionTimeOfDay_SK] as varchar(1000))
[ProductionTimeOfDay_SK]
,cast([ProductionType_SK] as varchar(1000)) [ProductionType_SK]
,cast([Shift_SK] as varchar(1000)) [Shift_SK]
,cast([Site_SK] as varchar(1000)) [Site_SK]
,cast([tBelt] as varchar(1000)) [tBelt]
,FORMAT([ModifiedAt],'yyyy-MM-dd HH:mm:ss.fffffff') [ModifiedAt]
,FORMAT([SourceUpdatedAt],'yyyy-MM-dd HH:mm:ss.fffffff')
[SourceUpdatedAt]
FROM [ORXX].[public_XX].[fact_FixedXXXX]
Operation on target cp_data_movement failed: ErrorCode=PolybaseOperationFailed,'Type=Microsoft.DataTransfer.Common.Shared.HybridDeliveryException,Message=Error happened when loading data into SQL Data Warehouse. Operation: 'Polybase operation'.,Source=Microsoft.DataTransfer.ClientLibrary,''Type=System.Data.SqlClient.SqlException,Message=HdfsBridge::recordReaderFillBuffer - Unexpected error encountered filling record reader buffer: ClassCastException: class parquet.io.api.Binary$ByteArraySliceBackedBinary cannot be cast to class java.lang.Double (parquet.io.api.Binary$ByteArraySliceBackedBinary is in unnamed module of loader 'app'; java.lang.Double is in module java.base of loader 'bootstrap'),Source=.Net SqlClient Data Provider,SqlErrorNumber=106000,Class=16,ErrorCode=-2146232060,State=1,Errors=[{Class=16,Number=106000,State=1,Message=HdfsBridge::recordReaderFillBuffer - Unexpected error encountered filling record reader buffer: ClassCastException: class parquet.io.api.Binary$ByteArraySliceBackedBinary cannot be cast to class java.lang.Double (parquet.io.api.Binary$ByteArraySliceBackedBinary is in unnamed module of loader 'app'; java.lang.Double is in module java.base of loader 'bootstrap'),},],'

Answer 1

Reasons for this error can be,
Order of the columns in the target table is not matching with the source table. So, there will be data type mismatch
Data types in parquet file is Incompatible to target tables' data type.
Solution:
Make sure the order of the columns are same as in parquet staging file.
Keep the same data types in source columns and target columns.