How to access output of any activity in another connected activity. - Lookup Activity

Accessing Pipeline Variable Array elements in another activity by.

@variable('NameOfPipelineVariable')[0]   -- 1st element
@variable('NameOfPipelineVariable')[1]   -- 2nd element


@concat(variable('NameOfPipelineVariable')[0],variable('NameOfPipelineVariable')[1])



@{activity('Copy1').output.dataWritten}

Accesses a property of the previous copy activity and passes the value of dataWritten.

or 

@activity('LookupTableList').output.value --- this will return full dataset i.e. all records returned by SQL in an activity.



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@{activity('CopyBlobtoBlob').error.message - For the failure case, pass the error output instead of 

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First Activity outputs a column named NewWatermarkvalue.
select MAX(LastModifytime) as NewWatermarkvalue from data_source_table
Below is how you access the output of the above activity in another activity in the same pipeline

@{activity('LookupOldWaterMarkActivity').output.firstRow.WatermarkValue}