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verdict-project / verdict

Interactive-Speed Analytics: 200x Faster, 200x Fewer Cluster Resources, Approximate Query Processing
http://verdictdb.org
Apache License 2.0
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verdictdbblock question #360

Closed solangepaz closed 5 years ago

solangepaz commented 5 years ago

Is it normal for the verdictdbblock value to always be 0?

pyongjoo commented 5 years ago

It could happen if your dataset contains less than one million tuples.

solangepaz commented 5 years ago

OK thank you. Is the data stored in some table with the samples, or does this just happen when the queries are being executed through the DAG?

pyongjoo commented 5 years ago

A sample (or equivalently, scramble) table is created when you issue a CREATE SCRAMBLE ... query.

The scramble table is materialized as a regular table in your database along with materialized verdictdbblock. This means "always 0" is stored in the table (not happen at query time).

solangepaz commented 5 years ago

And verdictdbtemp is used for what? When I create a scramble the verdictdbtemp has nothing ...

pyongjoo commented 5 years ago

The schema is used for storing temporary tables (and removed when you exit VerdictDB). For simple queries, no temporary tables are created, so what you see is expected.

solangepaz commented 5 years ago

Ok, thank you.