Azure Synapse Copy Upsert with Pipeline Parameter

I am trying to Parameterize Synapse Copy Upsert Keys using pipeline parameters with

@pipeline().parameters.Upsert_Column_1

But I am getting following error

Expression of type: 'String' does not match the field: 'writeBehaviorKeys'.
Expected type is 'Array' or 'Object'.

Also Can I pass list of Column names to Upsert_Column_1 if I have more than one column ? https://learn.microsoft.com/en-us/fabric/data-factory/connector-azure-synapse-analytics-copy-activity#destination

What is the correct way to do this ?

Expression of type: 'String' does not match the field: 'writeBehaviorKeys'. Expected type is 'Array' or 'Object'

The error message indicates that the value of the parameter to be of array type and the value you passed is of string type. You can pass more than one column names as a parameter value to the Key columns field of upsert copy activity. Below is the approach to do this.

• Create a parameter of type Array

• Add the dynamic expression @pipeline().parameters_Upsert_Column in the key columns field.

• If you want to upsert the data based on the fields like, "id" and "WorkOrderId" , you can pass the value of parameter as [ "id", "WorkOrderId" ] . This is the format for the value to be passed as value to key column parameter.