Vfrdtyky

I've created DT tables with links between master table, and child tables, which has child table etc...

I click on table master and I go from table to tables. And sometimes the initial selection is lost.

The initial goal was to have 2 database, archive and present time. I have a radio button to switch between the 2 database. So I have to put in all reactive function a function to reconnect or not to the correct chosen database.

Is a question for stackoverflow or a bug ?

This is for a big application.

But I have the same issue for a simple (old) application without DT and without reconnection between database.

The simple and the big Shiny applications are multi-user and each user could use multi-tab on their browser.

Thanks in advance :)

My structure of the big application:

server.R

database_name_decale<-"blabla_decale"

database_name_archive<-"blabla_archive"



connexion_bdd_odbc_decale_txt <- paste0('driver={ODBC Driver 17 for SQL Server};server=blabla;database=',database_name_decale,';uid=xxx;pwd=xxx;')

connexion_bdd_odbc_archive_txt <- paste0('driver={ODBC Driver 17 for SQL Server};server=blabla;database=',database_name_archive,';uid=xx;pwd=xx;')

...

shinyServer(function(input, output, session) {

  react <- reactiveValues( connexion_bdd = 0) 

  observeEvent(

  c(

    input$radiob.ChoixBase

  ),

  {

   Init_cnx_bdd.fct_react (input,output,session, change_base= TRUE)



 })

...

  observeEvent(input$NavTabPanels, {

    Init_cnx_bdd.fct_react (input,output,session, change_base= FALSE)

    if (input$NavTabPanels=="My_Menu") {

...

      My_Menu_maitre.tab.fct_react (input,output,session)  

    }

  })  

...

  My_Menu_maitre.tab.fct_react <- function (input,output,session) {

...

    detail.table <-  reactive({

      Init_cnx_bdd.fct_react (input,output,session, change_base = FALSE)

      input_appelant=  input$My_Menu_maitre_rows_selected

      validate(

        need(!is.null(input_appelant) , "Select a line from master")

      )                 

      res<-  data.frame() 

      table_details <-subset( My_Menu_maitre.table()[as.integer(input_appelant), ],

                              select=c("id_num"))

      res<- detail.reqSQL.fct (react$connexion_bdd,as.data.frame(table_details))            

      return(res)

    })  

...

    sub_detail.table <-  reactive({...})

...

    sub_sub_detail.table <-  reactive({...})

...

    sub_sub_sub_detail.table <-  reactive({...})

With this function

Init_cnx_bdd.fct_react <- function (input,output,session,   change_base) {

    req(react$connexion_bdd)

    if(input$radiob.ChoixBase == "BaseActuelle")   {

      output$BaseCouranteTxt <-renderText({"Actuelle"})

      if (change_base==TRUE) {

          tryCatch(

            {

              odbcClose(react$connexion_bdd)

            },

            error=function(e) { # print("e")

              },

            warning=function(w) { # print("w")  

              }

          )

          react$connexion_bdd<-odbcDriverConnect(connexion_bdd_odbc_decale_txt)

      } else {

          tryCatch(

            {

              odbcGetInfo(react$connexion_bdd)

            },

            error=function(e) {   print("e")

              react$connexion_bdd<-odbcDriverConnect(connexion_bdd_odbc_decale_txt)

            },

            warning=function(w) {  print("w")

            }

          )

      }



}



    if(input$Technique.Connexions.radiob.ChoixBase == "BaseArchive")   {

      output$Home.Technique.BaseCouranteTxt <-renderText({"Archive"})

      if (change_base==TRUE) {

          tryCatch(

            {

              odbcClose(react$connexion_bdd)

            },

            error=function(e) {  #print("e")

            },

            warning=function(w) { # print("w")   

            }

          )

          react$connexion_bdd<-odbcDriverConnect(connexion_bdd_odbc_archive_txt)

      } else {

        tryCatch(

          {

            odbcGetInfo(react$connexion_bdd)

          },

          error=function(e) { #  print("e")

            react$connexion_bdd<-odbcDriverConnect(connexion_bdd_odbc_archive_txt)

          },

          warning=function(w) { # print("w")

          }

        )

      }



    }

}

My structure of the little application:

server.R

connexion_bdd_odbc_txt='driver={ODBC Driver 11 for SQL Server};server=xxx;database=blabla_decale;uid=xx;pwd=xxx;'

...

shinyServer(function(input, output,session) {

...

table.brut<-reactive({

  connexion_bdd <- odbcDriverConnect(connexion_bdd_odbc_txt, readOnly = TRUE)  

  table<-sqlQuery(connexion_bdd, "SELECT * FROM blabla")

  odbcClose(connexion_bdd)

  table<-as.data.frame(table)



  return(table)

})

...

and other tables and reactive function, not of the DT package, and a few linked between them.

It seems that I use the "anti-solution" (named by Joe Cheng in his video tutorial).

anti-solution

observe ({

    df<-head(cars, input$nrows)

    output$plot <- renderPlot(plot(df))

})

good solution

output$plot <- renderPlot({

    plot(head(cars, input$nrows))

})

I am going to modify my code, it is solved.

https://github.com/rstudio/shiny/issues/2262

edit 17/1/2018

For information: the cause of lost selections was not only the use of "anti-solution". After the correction the issue was going on again a little.

I have replaced RODBC by DBI and RStudio/odbc, and the issue doesn't occur anymore.