# Queryverse @map question

**URL:** <https://discourse.julialang.org/t/queryverse-map-question/12484>\
**Category:** Data\
**Tags:** queryverse\
**Created:** [July 19, 2018, 8:20am UTC](https://discourse.julialang.org/t/queryverse-map-question/12484 "2018-07-19T08:20:55Z")\
**Posts on this page:** 1\
**Showing post:** 2

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**Author:** ![swt30](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/swt30/32/4667_2.png) [@swt30](https://discourse.julialang.org/u/swt30)\
**Post date:** [July 19, 2018, 11:27am UTC](https://discourse.julialang.org/t/queryverse-map-question/12484/2 "2018-07-19T11:27:07Z")

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Are you running this in the REPL? It looks like Query cannot be certain of the types of the values `m` and `sa` because they are non-constant globals, and I think Query relies on type inference to know what the final column types should be. The first example is okay because the 2 in `^2` is hardcoded and the compiler knows its type can’t change.

I understand there are [plans](https://discourse.julialang.org/t/using-a-string-variable-in-a-query-jl-query/7372/9) to remove this reliance on type inference in the future. But for now, if you wrap all the code in a function or declare the variables as constant beforehand (e.g. `const m = 2979.413793`) then it should work.

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