shinyApp with mysql database - sql

Question

shinyApp code is attached. I'm using data from mysql database and want to display data table based on the query and str and summary of the data. Code is running properly. Do I need to connect to database again and again to get displays of str, summary and table in my shiny app?
library(shiny)
library(DBI)
library(RMySQL)
ui <- fluidPage(
sidebarLayout(
sidebarPanel(
selectInput("dataset", "Choose a dataset:",
choices = c("city", "country","countrylanguage")),
numericInput("obs", "Number of observations to view:", 10),
submitButton("Update View")
),
mainPanel(
tabsetPanel(tabPanel("Table",tableOutput("view")),
tabPanel("Str",verbatimTextOutput("dump")),
tabPanel("Summary",verbatimTextOutput("stats"))
))
)
)
# Define server logic required to summarize and view the
# selected dataset
server<-function(input, output) {
output$view <- renderTable({
conn <- dbConnect(drv = RMySQL::MySQL(),dbname = "world",host = "localhost",username = "root",password = "xxxx")
on.exit(dbDisconnect(conn), add = TRUE)
head(dbReadTable(conn = conn, name = input$dataset), n = input$obs)
})
output$dump <- renderPrint({
conn <- dbConnect(drv = RMySQL::MySQL(),dbname = "world",host = "localhost",username = "root",password = "xxxx")
on.exit(dbDisconnect(conn), add = TRUE)
str(dbReadTable(conn = conn, name = input$dataset))
})
output$stats <-renderPrint({
conn <- dbConnect(drv = RMySQL::MySQL(),dbname = "world",host = "localhost",username = "root",password = "xxxx")
on.exit(dbDisconnect(conn), add = TRUE)
summary(dbReadTable(conn = conn, name = input$dataset), n = input$obs)
})
# Return the requested dataset
datasetInput <- reactive({
switch(input$dataset
)})
}
shinyApp(ui, server)