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I had 3 jobs in my Redshift cluster. First of them was querying two tables A and B and then inserting data to table B. Second transaction was removing and inserting to table A. Third transaction was just reading A and B. The timeline was: First transaction reads Second transaction deletes, inserts and commits First … Continue reading Aborted transactions in Redshift due to Serializable isolation level 2
This is the fifty sixth part of the ILP series. For your convenience you can find other parts in the table of contents in Part 1 – Boolean algebra Today we are going to benchmark factorization. First, let’s start with the code: Depending on the size of solver representation (how many bits we use to … Continue reading ILP Part 56 – Factorization benchmarking
This is the sixth part of the ML series. For your convenience you can find other parts in the table of contents in Part 1 – Linear regression in MXNet Today we are going to implement a matrix multiplication in Redshift. Let’s go. First, let’s see what we want to calculate: Nothing fancy. … Continue reading Machine Learning Part 6 — Matrix multiplication in SQL
This is the fifth part of the Turing Machine series. For your convenience you can find other parts in the table of contents in Part 1 – Addition Today we check whether a string has exactly twice as many ones as zeroes. States: The input looks like this: Transition table:
This is the fourth part of the Turing Machine series. For your convenience you can find other parts in the table of contents in Part 1 – Addition Today we subtract two numbers. This is very similar to addition so should be pretty readable. States: The input looks like this: Transition table: