How to escape characters in SQL code in an R Markdown chunk? - sql

Question

```
{r setup, include=FALSE}
knitr::opts_chunk$set(echo = TRUE)
library(tidyverse)
library(odbc)
library(DBI)
library(dbplyr)
```
```{sql, connection=con, output.var="df"}
SELECT DB_Fruit.Pear, Store.Name, Cal.Year, Sales.Qty FROM DB_Fruit
```
#> Error: unexpected symbol in "SELECT DB_Fruit.Pear"
I'm attempting to run SQL code in an R Markdown chunk as shown above. I'm getting the "unexpected symbol" error shown above. My best guess is that I need to escape the underscore with something such as \_ or \\_ but neither of those makes my error go away.
If I instead query using DBI (shown below) I do not get any errors:
df <- dbGetQuery(con,'
SELECT DB_Fruit.Pear, Store.Name, Cal.Year, Sales.Qty
FROM DB_Fruit
')
Maybe the dbGetQuery function is able to interpret things such as underscores _ correctly whereas the regular R Markdown parser can't? Or maybe there's blank spaces that have been copy/pasted as some weird unicode characters that again dbGetQuery function is able to interpret whereas the regular R Markdown parser can't?
What's the likely culprit and what do I do about it?

Answer 1

Your chunk header probably should be
{SQL, connection=con, output.var="df"}
instead of
{r SQL, connection=con, output.var="df"}

Answer 2

You have to use "Chunk Output Inline" in the Rmarkdown document
---
editor_options:
chunk_output_type: inline
---