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-- show running queries (pre 9.2)
SELECT procpid, age(clock_timestamp(), query_start), usename, current_query 
FROM pg_stat_activity 
WHERE current_query != '<IDLE>' AND current_query NOT ILIKE '%pg_stat_activity%' 
ORDER BY query_start desc;

-- show running queries (9.2)
SELECT pid, age(clock_timestamp(), query_start), usename, query 
FROM pg_stat_activity 
WHERE query != '<IDLE>' AND query NOT ILIKE '%pg_stat_activity%' 

th3hunt

If you are on a Mac, substitute command for control. Don't type the + (it means press both keys at once).

Shortcuts when in either command mode (outside the cells) or edit mode (inside a cell):

• Shift + Enter run selected cell or cells - if no cells below, insert a code cell below

• Ctrl + B toggle hide/show left sidebar

• Ctrl + S save and checkpoint

• Ctrl + Shift + S save as

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Create your library

• Initialize project npm init -y
• Create esm module ./src/esm/my-lib.js

  function addNumber(value, value2) {
    return value + value2;
  }
  
  export { addNumber };

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HTTP Streaming (or Chunked vs Store & Forward)

The standard way of understanding the HTTP protocol is via the request reply pattern. Each HTTP transaction consists of a finitely bounded HTTP request and a finitely bounded HTTP response.

However it's also possible for both parts of an HTTP 1.1 transaction to stream their possibly infinitely bounded data. The advantages is that the sender can send data that is beyond the sender's memory limit, and the receiver can act on

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####
# ZSH function to auto-switch to correct Node version
#   https://gist.github.com/callumlocke/30990e247e52ab6ac1aa98e5f0e5bbf5
#
# - Searches up your directory tree for the closest .nvmrc, just like `nvm use` does.
#
# - If you are already on the right Node version, IT DOES NOTHING, AND PRINTS NOTHING.
#
# - Works correctly if your .nvmrc file contains something relaxed/generic,
#   like "4" or "v12.0" or "stable".

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PSQL

Magic words:

psql -U postgres

Some interesting flags (to see all, use -h or --help depending on your psql version):

• -E: will describe the underlaying queries of the \ commands (cool for learning!)
• -l: psql will list all databases and then exit (useful if the user you connect with doesn't has a default database, like at AWS RDS)

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AWS ECS Deploy Permissions

In order to be able to deploy using the scripts provided by npm scripts for AWS ECS make sure your user is part of an IAM Group that has the following inline policy applied to it.

Note: This may not be complete.

{
    "Version": "2012-10-17",
    "Statement": [

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What is your folder-structure preference for a large-scale Node.js project?

0: Starting from Rails

This is the reference point. All the other options are based off this.

|-- app
|   |-- controllers
|   |   |-- admin

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Clustering: The basics

The trick? pass the file descriptor from a parent process and have the server.listen reuse that descriptor. So multiprocess in their own memory space (but with ENV shared usually)

It does not balance, it leaves it to the kernel.

In the last nodejs > 0.8 there is a cluster module (functional although marked experimental)

• http://nodejs.org/api/cluster.html
• Simple cluster example:

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What forces layout / reflow

All of the below properties or methods, when requested/called in JavaScript, will trigger the browser to synchronously calculate the style and layout*. This is also called reflow or layout thrashing, and is common performance bottleneck.

Element

Box metrics

• elem.offsetLeft, elem.offsetTop, elem.offsetWidth, elem.offsetHeight, elem.offsetParent
• elem.clientLeft, elem.clientTop, elem.clientWidth, elem.clientHeight
• elem.getClientRects(), elem.getBoundingClientRect()