“How do I move my R scripts stored in one database instance to another? I have my development/test system and want to migrate to production.”

Users of Oracle R Enterprise Embedded R Execution will often store their R scripts in the R Script Repository in Oracle Database, especially when using the ORE SQL API. From previous blog posts, you may recall that Embedded R Execution enables running R scripts managed by Oracle Database using both R and SQL interfaces. In ORE 1.3.1., the SQL API requires scripts to be stored in the database and referenced by name in SQL queries. The SQL API enables seamless integration with database-based applications and ease of production deployment.

Loading R scripts in the repository

Before talking about migration, we’ll first introduce how users store R scripts in Oracle Database. Users can add R scripts to the repository in R using the function ore.scriptCreate, or SQL using the function sys.rqScriptCreate.

For the sample R script

    id <- 1:10
    plot(1:100,rnorm(100),pch=21,bg="red",cex =2)
    data.frame(id=id, val=id / 100)

users wrap this in a function and store it in the R Script Repository with a name. In R, this looks like

ore.scriptCreate("RandomRedDots",
function () {
line-height: 115%; font-family: "Courier New";">     id <- 1:10
    plot(1:100,rnorm(100),pch=21,bg="red",cex =2)
    data.frame(id=id, val=id / 100))
})

In SQL, this looks like

begin
sys.rqScriptCreate('RandomRedDots',
 'function(){
    id <- 1:10
    plot(1:100,rnorm(100),pch=21,bg="red",cex =2)
    data.frame(id=id, val=id / 100)
  }');
end;
/

The R function ore.scriptDrop and SQL function sys.rqScriptDrop can be used to drop these scripts as well. Note that the system will give an error if the script name already exists.

Accessing R scripts once they’ve been loaded

If you’re not using a source code control system, it is possible that your R scripts can be misplaced or files modified, making what is stored in Oracle Database to only or best copy of your R code. If you’ve loaded your R scripts to the database, it is straightforward to access these scripts from the database table SYS.RQ_SCRIPTS. For example,

select * from sys.rq_scripts where name='myScriptName';

From R, scripts in the repository can be loaded into the R client engine using a function similar to the following:

ore.scriptLoad <- function(name) {
query <- paste("select script from sys.rq_scripts where name='",name,"'",sep="")
str.f <- OREbase:::.ore.dbGetQuery(query)
assign(name,eval(parse(text = str.f)),pos=1)
}

ore.scriptLoad("myFunctionName")

This function is also useful if you want to load an existing R script from the repository into another R script in the repository – think modular coding style. Just include this function in the body of the other function and load the named script.

Migrating R scripts from one database instance to another

To move a set of functions from one system to another, the following script loads the functions from one R script repository into the client R engine, then connects to the target database and creates the scripts there with the same names.

scriptNames <- OREbase:::.ore.dbGetQuery("select name from sys.rq_scripts where name not like 'RQG$%' and name not like 'RQ$%'")$NAME

for(s in scriptNames) {
cat(s,"\n")
ore.scriptLoad(s)
}

ore.disconnect()
ore.connect("rquser","orcl","localhost","rquser")

for(s in scriptNames) {
cat(s,"\n")
ore.scriptDrop(s)
ore.scriptCreate(s,get(s))
}

Best Practice

When naming R scripts, keep in mind that the name can be up to 128 characters. As such, consider organizing scripts in a directory structure manner. For example, if an organization has multiple groups or applications sharing the same database and there are multiple components, use “/” to facilitate the function organization:

line-height: 115%;">ore.scriptCreate("/org1/app1/component1/myFuntion1", myFunction1)
ore.scriptCreate("/org1/app1/component1/myFuntion2", myFunction2)
ore.scriptCreate("/org1/app2/component2/myFuntion2", myFunction2)
ore.scriptCreate("/org2/app2/component1/myFuntion3", myFunction3)
ore.scriptCreate("/org3/app2/component1/myFuntion4", myFunction4)

Users can then query for all functions using the path prefix when looking up functions.