This is the last part of a three part series examining the Postgres join algorithms.
While a hash join is usually the fastest join algorithm, it is only so when it can be performed in memory. When Postgres thinks the hash … Read the rest
Postgres Hash Joins
This is part two of a three part series examining the Postgres join algorithms.
Of the join algorithms Postgres has available, the hash join is usually the fastest. The main downside is hash joins only work where the join condition is an … Read the rest
Postgres Nested Loop Joins
This is the first part of a three part series examining the Postgres join algorithms.
For those who need a reminder, a join between two tables results in every pair of rows where some condition is true. Given a query of … Read the rest
Postgres Bitmap Scans
This is the final part of a three part series exploring the different ways Postgres can retrieve rows from a table.
One major restriction with regular index scans is that they can only use a single index. Sometimes a query … Read the rest
Postgres Index Scans
This is part two of a three part series examining the different ways Postgres can fetch rows from a table.
Usually a sequential scan winds up being pretty slow. A sequential scan needs to read the entire table in order … Read the rest
Postgres Sequential Scans
This is part one of a three part series on the main ways Postgres has of fetching rows from a table.
Of the three main ways Postgres has fetching rows from a table, a sequential scan is the most basic. … Read the rest
Building Fizzbuzz in Fractran from the Bottom Up
In this post, I am going to show you how to write Fizzbuzz in the programming language Fractran. If you dont know, Fractran is an esoteric programming language. That means it is extraordinary difficult to write any program in Fractran. … Read the rest
How to Generate Self-Referential Programs
In this post, I am going to show you how to write programs that are self-referential. By self-referential, I mean programs which are able to obtain their own source code without any external input. In other words, they won’t just … Read the rest
Loops in Lisp Part 4: Series
This is part four of Loops in Lisp. Follow one of the following links for part one – goto, two – loop, or three – iterate).
One of the many advantages of programming in a functional style … Read the rest
Loops in Lisp Part 3: Iterate
This is part 3 of Loops in Lisp. For part 1 on how you can build any kind of looping construct you want out of just goto and macros, click here. For part 2 on Loop, click here.… Read the rest