Azure Datafactory can't handle empty json array in blob

Question

in azure data factory dataset, using the copy activity to load json blob to sqldb, when the json blob is an empty array "[]" the copy activity gets stuck with error.

{
    "errorCode": "2200",
    "message": "Failure happened on 'Source' side. ErrorCode=UserErrorTypeInSchemaTableNotSupported,'Type=Microsoft.DataTransfer.Common.Shared.HybridDeliveryException,Message=Failed to get the type from schema table. This could be caused by missing Sql Server System CLR Types.,Source=Microsoft.DataTransfer.ClientLibrary,''Type=System.InvalidCastException,Message=Unable to cast object of type 'System.DBNull' to type 'System.Type'.,Source=Microsoft.DataTransfer.ClientLibrary,'",
    "failureType": "UserError",
    "target": "BP_acctset_Blob2SQL",
    "details": []
}

Answer 1

1. Use Get Metadata to get the file size.

2. Use if condition to juge if the size is greater than 2. If true then exec copy activity.