bensheldon

In my application every time I send a newsletter to a User, I create a NewsletterDelivery record. I frequently want to be able to query, for each user, what is the most recent newsletter delivery record. This is called a "last n per group" query and a LATERAL JOIN is the best way to do it imo. But the query I've been using (and I've told people to use, and seen blogged about) is not very good, because the conditions don't get pushed down into the subselect which means that the query ends-up lateral-joining all the records before it applies the conditions for the association.

Instead of doing subselect_table.* the better query does association.id AS assocation_id, subselect_table.id, subselect_table.title, .... and enumerates over all of the columns. This allows the association query, which Active Record tacks on at the end as WHERE association_id = $1 or WHERE association_id IN ($1, $2, $3, ...) to be pushed down c

lukaszkorecki

.ONESHELL:
test: .SHELLFLAGS := -i
test: SHELL := bb

test:
  (println :wow)
  (require '[clojure.string :as s])
  (s/reverse (slurp "./Makefile"))

cldwalker

Spike

I looked into the state of GraalVM and Clojure and wrote some small work-related scripts.

GraalVM Build Tools

• Downloaded GraalVM and set $GRAALVM_HOME
• Found two main libraries for building GraalVM CLIs - https://github.com/luchiniatwork/cambada#packaging-as-a-native-image and https://github.com/taylorwood/clj.native-image (or https://github.com/taylorwood/lein-native-image for the lein equivalent). I chose clj.native-image as it seemed more focused on doing one thing well.
• First tried its template example which was easy to follow.
• Then added a graalvm build to one of our small cli tools
• Found it to be pretty straightforward except for a stdout flushing issue that was trivial to fix

stevenharman

Heroku Release Phase + Review Apps + Rails

This is a simplified, but fairly thorough, set of scripts and configuration to enable Heroku Release Phase for Rails apps. Further, this particular set up plays nicely with Heroku Review Apps in that the release phase script will:

1. Fail, loudly, if the DB does not yet exist.
2. Load the DB schema if the current schema version (as determined by bin/rails db:version) is 0.
3. Run DB migrations otherwise.

For a "normal" app that usually means it will run the DB migrations.

lauraturk

Deploying from circleci2.0 to Heroku

Resources:

• circleci 2.0 docs
• Managing SSH Keys on Heroku

Steps:

Prerequisites:

• Heroku CLI installed on your computer
• A project deployed to Heroku

yogthos

#!/usr/bin/env lumo
(ns spacedl.spacedl
  (:require [cljs.nodejs :as node]
            [clojure.pprint :refer [pprint]]
            [clojure.string :as string :refer [join split starts-with?]]
            [cljs.core :refer [*command-line-args*]]))

(node/enable-util-print!)
(.on js/process "uncaughtException" #(js/console.error %))

jdevoo

"**************************************************************************
 * Allowable characters:                                                  *
 *    - a-z                                                               *
 *    - A-Z                                                               *
 *    - 0-9                                                               *
 *    - .+/\*~<>@%|&?                                                     *
 *    - blank, tab, cr, ff, lf                                            *
 *                                                                        *
 * Variables:                                                             *
 *    - variables must be declared before use                             *

ghadishayban

(ns docker-tag-paginate
  (:require [clj-http.lite.client :as client]
            [cheshire.core :as json]
            [clojure.pprint :refer [print-table]]))

(def base-url "https://registry.hub.docker.com/v2")

;; (progression pos? dec 15)

(defn progression

favila

(ns favila.datomic-util.restore-datoms
  "A \"manual\" datomic database restore.
  
  Writes raw datoms (stored in a stream written by d/datoms) to an empty database.
  Useful for memory databases: you can write out all the datoms in it, then read
  them into another database. (Note mem dbs have no log or retractions)."
  (:require [datomic.api :as d]
            [clojure.edn :as edn]))

(defrecord datom [e a v tx added?])

stuarthalloway

(ns user)

(def app
  "Intenal Helper"
  (fnil conj []))

(defprotocol PathSeq
  (path-seq* [form path] "Helper for path-seq"))

(extend-protocol PathSeq