This card is just about creating simple PostgreSQL dumps. This is no instruction for a backup strategy nor a guide for SQL dump performance optimization. Read before starting

...assume that all commands will be executed as local postgres user on a database server master. Please mind that you should stop the replication on a slave PostgreSQL server before...

github.com

...Request, visit /__better_errors on your app's root path (e.g. http://localhost:3000/__better_errors). It shows the error page for the last exception that occurred, even when it has been triggered...

...For ages, CSS transforms had to be defined using the transform property. For a single transformation, this was something like transform: scale(1.5), and multiple transformations could be applied by...

.example { transform: scale(1.5) rotate(45deg) translateY(-50%); } All modern browsers (Chrome & Edge 104+, Firefox 72+, Safari 14.1+, Samsung Internet 20+) also support individual properties for transforms.

Or: How to avoid and refactor spaghetti code Please note that I tried to keep the examples small. The effects of the methods in this card are of course much...

...more significant with real / more complex code. What are the benefits of more modular code? Code is written once but read often (by your future self and other developers who...

...you have too many inotify instances you may run into limits of your operating system. To find out which process is using them all up you can run:

...does a feature look and feel). Frequent deploy gets changes to users faster. We sleep better, because we know stuff still works. Make sure no one removes a feature by...

...to write both with "should" and "expect" You should know how to enable the old #should-syntax in RSpec 3 Understand what "Test the behavior, not the implementation" means.

...is a checklist I use to work on issues. For this purpose I extracted several cards related to the makandra process and ported them into a check list and refined...

...main/master branch Branch off the master with geordi branch or manually Name your branch like sort-users-by-name-73624, i.e. start with the issue id, then a shortened description...

When doing some meta-programming magic and you want to do something for all attributes of a class, you may need to access connection or some of its methods (e.g...

...will encounter fun errors such as: PG::ConnectionBad (for missing databases on PostgreSQL) ActiveRecord::StatementInvalid: PG::UndefinedTable (when database exists, but has no tables) Generally speaking, evaluating model columns during...

...of passwords for the root user and you prefer using a password for root. Solution Step 1 is getting a root mysql shell that allows us to change user credentials...

...and MySQL since they share names of binaries. sudo systemctl stop mysql sudo mysqld_safe --skip-grant-tables & This starts the mysql daemon in the background and we can now...

...come across objects created by some gem or framework. You don't have the source code at hand, still need to inspect this object. Here are some tools to do...

...from Object. This makes the methods list drastically more relevant. You can also try subtracting other base classes like ActiveRecord::Base.methods etc. To further narrow it down you can also...

ImageMagick can convert SVGs to raster image formats. Example for PNG: convert input.svg output.png If the SVG has a size of 24x24 (viewBox="0 0 24 24"), the resulting...

...PNG will also have a size of 24x24. Resizing An SVG's viewBox specifies the intended size, but vector image formats can be scaled freely. Resize flag (poor results)

Sometimes you have a file that is related to a project, while not actually being part of it. You'd like to keep them around, but others won't need...

...them – e.g. some notes, a log, or a database dump. Sure, you have a project directory – but all of it is tracked by Git. A project's tmp/ directory is...

PostgreSQL uses the C library's locale facilities for sorting strings: First, all the letters are compared, ignoring spaces and punctuation. It sorts upper and lower case letters together. So...

...the order will be something like a A b B c C Then, spaces and punctuation are compared to break ties. Example: Ruby PostgreSQL IMAGE3.jpg image2.jpg image.jpg image3.jpg image2.jpg

...RSpec assigns it a constant under RSpec::ExampleGroups. A describe Project do...

...end in spec/models/project_spec.rb defines RSpec::ExampleGroups::Project. That constant is harmless for the Ruby code in your specs...

Fix Anchor the class name: belongs_to :project, class_name: '::Project' compute_type short-circuits on a leading :: and skips the candidate walk entirely. Alternatively, move the throwaway...

...this.boundStopLock = this.stopLock.bind(this) // Stream rendering document.addEventListener("turbo:before-stream-render", this.boundLockTurboStreamRendering) // Form submission document.addEventListener("turbo:submit-start", this.boundStartLock) document.addEventListener("turbo:submit-end", this.boundStopLock) // Network activity document.addEventListener("turbo:before-fetch-request...

...render", this.boundStopLock) } disconnect() { // Stream rendering document.removeEventListener("turbo:before-stream-render", this.boundLockTurboStreamRendering) // Form submission document.removeEventListener("turbo:submit-start", this.boundStartLock) document.removeEventListener("turbo:submit-end", this.boundStopLock) // Network activity document.removeEventListener("turbo:before-fetch-request...

...tell npm to install a package globally with npm -g install @puppeteer/browsers. However, it seems that its not possible that npx can run commands from global packages without referencing the...

...image, where a testing chrome and chromedriver is installed with a global npm package. Since there is no local project it was more useful to install the package in a...

Module imports are hoisted (internally moved to the beginning of the current scope). Therefore, it doesn’t matter where you mention them in a module and the following...

Footgun example When you're not aware of import hoisting you may be surprised that your code runs in a different order than you see in the source file...

...text right next to the code: notes for other developers, and for your future self. You can imagine comments as post-its (or sometimes multi-sheet letters ...) on real-world...

...objects like cupboards, light switches etc. As always, with power comes responsibility. Code comments can go wrong in many ways: they may become outdated, silently move away from the code...

...use puppet-lint to find dead code in your project: # You probably need to set some ENV Variables, see https://github.com/voxpupuli/puppet-ghostbuster#environment-variables export HIERA_YAML_PATH="/home/bob/code/puppet/hiera.yaml" export PUPPETDB_URL...

...moving a file, your imports also need to change. To get around this, esbuild support a mechanism first introduced in TypeScript called "path aliases". It works like this:

...if you do use TypeScript): { "compilerOptions": { "baseUrl": "./app/assets", "paths": { "@/*": ["js/*"], "@images/*": ["images/*"], "@css/*": ["css/*"], "@spec/*": ["../../spec/js/*"] } }, "include": [] } (The include: [] only makes sense if you do not use Typescript. If you...

...discouraged to load your JavaScript by a tag in the : The reason is that a tag will pause the DOM parser until the script has loaded and executed. This will delay the browser's first contentful paint. A much better default is to load your scripts with a tag: A deferred script has many useful properties: It does not block the browser from rendering content. Deferred scripts...

...can query the entire DOM tree with querySelector() and friends. document.readyState is 'interactive'. Deferred scripts will run before the DOMContentLoaded event. That means if your code waits to initialize until...

In the past we validate and set default values for boolean attributes in Rails and not the database itself. Reasons for this: Older Rails didn't support database defaults when...

...the Rails upstream on constraints in the database, is adding default values in the schema of the database itself. We also encourage to set boolean attributes to not null. For...

...your lambda function via terraform, this code is usually zipped and uploaded to Amazon S3 by terraform. The ZIP file's hash is then stored to terraform's state. However...

...you're collaborating with colleages e.g. via git, each run of terraform will possibly see a different hash of the code's ZIP archive and try to replace the lambda...

...value and produce a lost update. The Postgres-native fix is to compute the increment server-side inside an atomic INSERT...

...ON CONFLICT DO UPDATE statement and gate it by...

...billing_period_id: current_billing_period.id ) end end Why a unique index The unique index is a storage-level constraint: Postgres rejects duplicate keys at insert time, before commit. Two consequences: