logjammin questions

• My data.table join exceeds memory limit on 64bit Windows machine with 32gb RAM
• What's the difference between WHERE and FILTER (WHERE) in PostgreSQL?
• PostgreSQL timeouts on local server with complex query and fairly large dataset
• In R, collapse over multiple logical rows of the same ID into 1 row
• In R, indicate whether another column has more than one unique value per ID
• In R, sample n rows from a df in which a certain column has non-NA values (sample conditionally)

logjammin answers