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Posts Tagged ‘Denodo’

Denodo useful Developer Commands/Info

In this area I will be posting Denodo useful commands/tricks. Below are few,

  1. context (‘querytimeout’ = )

Example:

context ('querytimeout' = '10800000')

Use above syntax at the end of SELECT statement to avoid default timeout which happens usually after 15 minutes.

  1. DESC VQL VIEW

Use it to get fields names and its data types

  1. MAP (,’$.Parent1.ChildElementName’)

Useful in SELECT or WHERE clause to get info from JSON column

  1. Use CTE’s or TEMP tables for intermediate data processing
  2. Escape character in Denodo is $. Useful when we search data with functions with REGEX
  3. Denodo Documentation: Select appropriate version. http://help.denodo.com/platform-docs/5.5/
  4. Support.Denodo.com : For Denodo customers to create case/ticket for questions/issues.
  5. DBeaver : I like this client tool because you will get to open multiple query windows and in each window you can run multiple commands at same time.

avoid time-out for Denodo ADO Net Source in SSIS

In SSIS, I was executing sql command in ADO Net Source of one of the Data Flow and was getting Time-out error after approximately 15 minutes. I used below clause after select statement.

context (‘querytimeout’ = ‘9000000’)

Here time is in milliseconds (in our case, ‘9000000’ is approx 2.5 hr).

For more info read “CONTEXT CLAUSE” in Denodo documentation in “Advanced VQL Guide”