bitemyapp/esqueleto

Calling `sum_` on an `Int` column and trying to use the result as an `Int` leads to a marshal error

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#82 opened on Mar 23, 2018

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bughelp wantedneeds discussion

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Description

It appears that (at least in Postgresql), summing a list of ints gives back a numeric. So when you call sum_ from esqueleto on an Int column and use the result as an Int you get a persist marshal error. IMO this should probably be solved on esqueleto's end, by either inserting an explicit cast or by restricting the return type of sum_ to ones which will not raise a marshal error.

Contributor guide

Research direction
Investigate the return type of sum in esqueleto and how PostgreSQL treats sum of integers as numeric. Consider adding an explicit cast or restricting the return type to avoid marshal errors.
Tech stack
haskell
Domain
backenddatabase
Issue type
Bug
DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.
2
Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.
1-3 hours
Activity statusHow available the issue appears right now: fresh, active, stale, blocked, or waiting on maintainer input.
Active
ClarityHow clearly the issue explains the expected change, acceptance criteria, and next step.
Clear
Prerequisites
HaskellSQLPostgreSQL
Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.
60