Set Session Command with Presto

[ejtesoriero]

Hi there!

I am connecting to a data source via a Simba Presto ODBC Driver.  There was an issue with the field names and was advised to run the below set session command to align the columns correctly.  I am not able to include the command in my SQL Editor or use it in the Pre SQL Statement.  Why am I able to run in DBeaver, but not in Alteryx?  Can you advise on how to successfully run the command?

The PreSQL Statement is:

set session datalake.parquet_use_column_names=true;

The error I am receiving is:

Error: Input Data (28): Error running PreSQL: "set session datalake.parquet_use_column_names=true;
": [Simba][Presto] (1060) Presto Query Error: line 1:1: Session property datalake.parquet_use_column_names does not exist (14)

[joshuaburkhow]

Hi @ejtesoriero 

I haven't seen the set session with underscores...I think it should be with dashes "set session datalake.parquet-use-column-names=true"

Try and see if it works 😉 

[ejtesoriero]

Still getting an error, but now it is different:

Error: Input Data (28): Executing PreSQL: "set session datalake.parquet-use-column-names=true" : [Simba][Presto] (1060) Presto Query Error: line 1:29: mismatched input '-'. Expecting: '.', '=' (1)
Error: Input Data (28): Error running PreSQL: "set session datalake.parquet-use-column-names=true": [Simba][Presto] (1060) Presto Query Error: line 1:29: mismatched input '-'. Expecting: '.', '=' (1)

Then I tried replacing the '-' with '.', but getting a different error:

Error: Input Data (28): Executing PreSQL: "set session datalake.parquet.use.column.names=true" : [Simba][Presto] (1060) Presto Query Error: line 1:1: Invalid session property 'datalake.parquet.use.column.names' (14)
Error: Input Data (28): Error running PreSQL: "set session datalake.parquet.use.column.names=true": [Simba][Presto] (1060) Presto Query Error: line 1:1: Invalid session property 'datalake.parquet.use.column.names' (14)

[kelly_gilbert]

Try a combination of the two! (period after your catalog name, and period after parquet, but hyphens in the use-column-names property):

datalake.parquet.use-column-names=true 

[ejtesoriero]

I am still getting an error using the command set session datalake.parquet.use_column_names=true

Error: Input Data (1): Executing PreSQL: "set session datalake.parquet.use_column_names=true" : [Simba][Presto] (1060) Presto Query Error: line 1:1: Invalid session property 'datalake.parquet.use_column_names' (14)
Error: Input Data (1): Error running PreSQL: "set session datalake.parquet.use_column_names=true;": [Simba][Presto] (1060) Presto Query Error: line 1:1: Invalid session property 'datalake.parquet.use_column_names' (14)

My manager suggested using the Run Command Tool.  I have never used that tool before, but researching it now.  Do you think that would be the fix?

[PhaniV]

Once EMR cluster was reset, it resolved similar issue.