Author Archives: mx
I noticed my dimension table was stuck when I query it for etl job and the truncate statement fails to return. “Locking is a protection mechanism that controls how many sessions can access a table at the same time and … Continue reading
Creating a Tableau Report level View Filter (1 report varying view depending on tableau user logged in)
Creating a Report level View Filter in Tableau (1 report varying view depending on tableau user logged in) use case: You want a report to show an employee’s daily sales and for the employee to only see his data and … Continue reading
Found on: http://www.datasciencecentral.com/ and https://www.linkedin.com/pulse/logistic-regression-vs-deep-neural-networks-david-young/ Sometimes a simple regression model will do.
mysql tricks: do instant table swap to mitigate mysql deadlock error. Continue reading
Assuming Redshift tables are un-compressed because most people don’t do it. list all the big tables by size, here’s a script run analyze compression analyze compression public.report_table_name; Example results: table column encoding est_reduction_pct report_table_name rowid raw 0 report_table_name create_date zstd 9.49 … Continue reading
Best practices for PySpark programming Programming in Spark using PySpark from Mostafa Elzoghbi History of SQL and all the advanced features over the last 30 years among big vendors. Modern SQL in Open Source and Commercial Databases from Markus Winand