- Algorithm interview – Big O
Big O is about how long an algorithm takes to run from start to end and how well it scales based on the size of the input or dataset. Big O is mostly measured based on the worst-case scenario even though some algorithms might finish early based on some logic. Here is another graph […]
- Postgres – Data Types
The choices you cannot cheaply undo later. `text` versus `varchar(n)` and why the length limit buys nothing, `numeric` for money and never a float, `timestamptz` versus `timestamp` and what actually gets stored, `uuid` alongside an integer key rather than instead of it, arrays, and why StayHub stores its enums as varchar. With a mapping table to Python and Java types.
- Postgres – Databases, Schemas, Roles and Privileges
A database holds schemas, a schema holds tables, and a role is both a user and a group. Creating an application account that is not a superuser: what `public` grants you by default and why the first thing to do is revoke it, GRANT versus ALTER DEFAULT PRIVILEGES and why the second one is the one people forget, search_path, and the owner/app/read-only split worth having on day one.
- Postgres – psql and the Tools You Actually Use
psql is the tool that ships with the database and the one every answer online assumes. The meta-commands worth memorising — \d, \d+, \di, \l, \dn, \x, \timing — the connection URI in full, running a file with ON_ERROR_STOP so a migration does not half-apply, and a .psqlrc that makes the shell bearable. Plus where a GUI still wins.
- Intellij Hot Keys
Reformat Code For Mac ⌥ ⌘ L command + option + l View Structure/Outline of Class command + 7