This is the place for discussing Chapter 3 of this book:

* Brendan Fong and David Spivak, _[Seven Sketches in Compositionality](http://math.mit.edu/~dspivak/teaching/sp18/7Sketches.pdf)_. See also the
[website with videos](http://math.mit.edu/~dspivak/teaching/sp18/).

Chapter 3 is about databases - and now we will finally meet categories, functors, and universal constructions.

Lectures will start on Monday 28 May 2018. But you can start reading the book and doing exercises now!

[[Fredrick Eisele]] is putting some exercises onto this forum. Please try some and put up your answers! If one of them is not up yet at the following location, you can put it there.

* [Exercise 1 - Chapter 3](https://forum.azimuthproject.org/discussion/2130)
* [Exercise 3 - Chapter 3](https://forum.azimuthproject.org/discussion/2131)
* [Exercise 4 - Chapter 3](https://forum.azimuthproject.org/discussion/2132)
* [Exercise 5 - Chapter 3](https://forum.azimuthproject.org/discussion/2133)
* [Exercise 7 - Chapter 3](https://forum.azimuthproject.org/discussion/2134)
* [Exercise 8 - Chapter 3](https://forum.azimuthproject.org/discussion/2135)
* [Exercise 9 - Chapter 3](https://forum.azimuthproject.org/discussion/2136)
* [Exercise 11 - Chapter 3](https://forum.azimuthproject.org/discussion/2137)
* [Exercise 13 - Chapter 3](https://forum.azimuthproject.org/discussion/2138)
* [Exercise 14 - Chapter 3](https://forum.azimuthproject.org/discussion/2139)
* [Exercise 17 - Chapter 3](https://forum.azimuthproject.org/discussion/2140)
* [Exercise 22 - Chapter 3](https://forum.azimuthproject.org/discussion/2141)
* [Exercise 23 - Chapter 3](https://forum.azimuthproject.org/discussion/2142)
* [Exercise 24 - Chapter 3](https://forum.azimuthproject.org/discussion/2143)
* [Exercise 25 - Chapter 3](https://forum.azimuthproject.org/discussion/2144)
* [Exercise 29 - Chapter 3](https://forum.azimuthproject.org/discussion/2145)
* [Exercise 31 - Chapter 3](https://forum.azimuthproject.org/discussion/2146)
* [Exercise 32 - Chapter 3](https://forum.azimuthproject.org/discussion/2147)
* [Exercise 35 - Chapter 3](https://forum.azimuthproject.org/discussion/2148)
* [Exercise 37 - Chapter 3](https://forum.azimuthproject.org/discussion/2149)
* [Exercise 39 - Chapter 3](https://forum.azimuthproject.org/discussion/2150)
* [Exercise 45 - Chapter 3](https://forum.azimuthproject.org/discussion/2151)
* [Exercise 48 - Chapter 3](https://forum.azimuthproject.org/discussion/2152)
* [Exercise 51 - Chapter 3](https://forum.azimuthproject.org/discussion/2153)
* [Exercise 53 - Chapter 3](https://forum.azimuthproject.org/discussion/2154)
* [Exercise 54 - Chapter 3](https://forum.azimuthproject.org/discussion/2155)
* [Exercise 59 - Chapter 3](https://forum.azimuthproject.org/discussion/2156)
* [Exercise 61 - Chapter 3](https://forum.azimuthproject.org/discussion/2157)
* [Exercise 62 - Chapter 3](https://forum.azimuthproject.org/discussion/2158)
* [Exercise 65 - Chapter 3](https://forum.azimuthproject.org/discussion/2158)
* [Exercise 66 - Chapter 3](https://forum.azimuthproject.org/discussion/2160)
* [Exercise 67 - Chapter 3](https://forum.azimuthproject.org/discussion/2161)
* [Exercise 72 - Chapter 3](https://forum.azimuthproject.org/discussion/2162)
* [Exercise 74 - Chapter 3](https://forum.azimuthproject.org/discussion/2163)
* [Exercise 75 - Chapter 3](https://forum.azimuthproject.org/discussion/2164)
* [Exercise 81 - Chapter 3](https://forum.azimuthproject.org/discussion/2165)
* [Exercise 82 - Chapter 3](https://forum.azimuthproject.org/discussion/2166)
* [Exercise 84 - Chapter 3](https://forum.azimuthproject.org/discussion/2167)