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copdips / upsert.py
Created March 9, 2019 01:10 — forked from bhtucker/upsert.py
A demonstration of Postgres upserts in SQLAlchemy
"""
Upsert gist
Requires at least postgres 9.5 and sqlalchemy 1.1
Initial state:
[]
Initial upsert:
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copdips / Types.md
Last active October 21, 2018 23:05 — forked from kevinblumenfeld/Types.md

Credit: Mark Kraus
Website: https://get-powershellblog.blogspot.com

Collection Type Guidence

When to use what

  • Use Arrays if you know the element types and have a fixed length and/or known-up-front collection size that will not change.
  • Use ArrayList if you have an unkown collection size with either unknown or mixed type elements.
  • Use a Generic List when know the type of the elements but not the size of the collection.
  • Use a HashTable if you are going to do key based lookups on a collection and don't know the object type of the elements.
  • Use a Dictionary<TKey, TValue> you are going to do key based lookups on a collection and you know the type of the elements.
  • Use a HashSet when you know the type of elements and just want unique values and quick lookups and assignmnets.