Shiny and real-time hookup to Oracle

[Jeff Chen]

Hi all,

Is it possible to develop a Shiny app, have it hooked up to a Oracle data warehouse so that the app can suck in new data on a daily basis? 

Thanks,

JC

[Joe Cheng]

Yes, although depending on how long it takes to "suck in new data", you might not want to have the data fetching happen in the Shiny process itself, as the data fetching will block the app from doing anything else. If it'll take a long time then you could just set up a separate R script for downloading the data to disk, and run it automatically using cron or something similar.

If you do want to run it in Shiny, then you would do it by setting up a reactive expression that does the querying and returns a data frame, and also calls invalidateLater with however long you want between refreshes.

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[Jeff Chen]

Thanks!

[Isabell Baldauf]

Dear Joe,

I'm trying to create an Shiny-App which can suck in new Oracle data.

Unfortunately it does not work and I do not know where my mistake lies.

Here is my mini example:

## ui.R
library(shiny)
library(ROracle)
library(ggplot2)

shinyUI(fluidPage(
  titlePanel("Prototyp Shiny"),
  sidebarLayout(
    sidebarPanel(
      numericInput(
        inputId = "anr",
        label="Artikelnummer",
        value=""
      )
    ),
   
    # Show a plot of the generated distribution
    mainPanel(
      dataTableOutput("anzk")
    )
  )
))

##Server.R

library(shiny)
library(ROracle)
library(ggplot2)

# Define server logic required to draw a histogram
shinyServer(function(input, output) {
    art_re <- reactive({
    drv <- dbDriver("Oracle")
    con <- dbConnect(drv,username="**",password="**",dbname="**")
    res <- dbSendQuery(con,paste0("select count(*) from kuart_mon where firma='00' and artnr=",input$anr,"and periode='201512'"))
   
    art_res <- fetch(res)
    dbDisconnect(con)
    art_res}) 

    renderTable({output$anzk <- art_re})
})

runApp('H:\\Profile\\Projekte\\Prototype_shiny\\app_1')

Thanks for your help.

[Isabell Baldauf]

 I have found my mistake. Thank you anyway :-)

[Joe Cheng]

Hopefully it was this?

    renderTable({output$anzk <- art_re})

becomes

    output$anzk <- renderTable({ art_re() })

On Fri, Jan 8, 2016 at 6:36 AM, Isabell Baldauf <isabell...@gmail.com> wrote:

 I have found my mistake. Thank you anyway :-)

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[Isabell Baldauf]

Yes exactly that was my mistake. Thanks Isabell

[prer...@gmail.com]

Hello Madlene,

Were you able to deploy Shiny app, using Oracle database?