R run sql query in parallel with foreach, DBI and odbc packages

sql_parallel_foreach_example.r

library(foreach)
library(doParallel)
library(DBI)

#Creating the cluster
cl <- makeCluster(detectCores() -1)

# Defining packages and variables for cluster
clusterEvalQ(cl, {
  library(odbc)
  library(DBI)
  
  conn <- dbConnect(odbc::odbc(),
                   .connection_string = "Driver={SQL Server};Server=MyServer;Database=MyDatabase;UID=MyUser;PWD=MyPwd;")
  NULL
})

#Register the Cluster
registerDoParallel(cl)

#Start the Parallel Loop
results <- foreach(i= 1:10, .combine = "rbind", .inorder = FALSE) %dopar% {
  sql_text <- "SELECT * FROM MyTable WHERE ID = ?id"
  sql_query <- DBI::sqlInterpolate(conn, sql_text, id = i)
  q <- DBI::dbGetQuery(conn, sql_query)
}

#Closing connection in all clusters
clusterEvalQ(cl, {
  dbDisconnect(conn)
})

# Stopping cluster
stopCluster(cl)
stopImplicitCluster()