Save Objects to a Datastore

2.2.3.5.3 Save Objects to a Datastore

The ore.save function saves one or more R objects in the specified datastore.

By default, OML4R creates the datastore in the current user schema. With the arguments to ore.save, you can provide the names of specific objects, or provide a list of objects. You can specify whether read privilege access to the datastore can be granted to other users. You can specify a particular R environment to search for the objects you would like to save. The overwrite and append arguments are mutually exclusive. If you set the overwrite argument to TRUE, then you can replace an existing datastore with another datastore of the same name. If you set the append argument to TRUE, then you can add objects to an existing datastore. With the description argument, you can provide some descriptive text that appears when you get information about the datastore. The description argument has no effect when used with the append argument.

Example 2-18 Saving Objects and Creating a Datastore

This example demonstrates creating datastores using different combinations of arguments.

# Create some R objects.
df1 <- data.frame(x1 = 1:5, y1 = letters[1:5])
df2 <- data.frame(x2 = 5:1, y2 = letters[11:15])
iris_of <- ore.push(iris)

# Create a database table and an OML4R proxy object for the table.
ore.drop("AIRQUALITY")
ore.create(airquality, table = "AIRQUALITY")

# List the R objects.
ls()

# List the OML4R proxy objects.
ore.ls()

# Save the proxy object and all objects in the current workspace environment
# to the datastore named ds1 and supply a description.
ore.save(AIRQUALITY, list = ls(), name = "ds1", description = "My private datastore")

# Create some more objects.
x <- stats::runif(20)  # x is an object of type numeric.
y <- list(a = 1, b = TRUE, c = "hoopsa")
z <- ore.push(x)  # z is an object of type ore.numeric.

# Create another datastore.
ore.save(x, y, name = "ds2", description = "x and y")

# Overwrite the contents of datastore ds2.
ore.save(x, name = "ds2", overwrite = TRUE, description = "only x")

# Append object z to datastore ds2.
ore.save(z, name = "ds2", append = TRUE)

Listing for This Example

R> # Create some R objects.
R> df1 <- data.frame(x1 = 1:5, y1 = letters[1:5])
R> df2 <- data.frame(x2 = 5:1, y2 = letters[11:15])
R> iris_of <- ore.push(iris)
R> 
R> # Create a database table and an OML4R proxy object for the table.
R> ore.drop("AIRQUALITY")
R> ore.create(airquality, table = "AIRQUALITY")
R> 
R> # List the R objects.
R> ls()
[1] "df1"     "df2"     "iris_of"
R> 
R> # List the OML4R proxy objects.
R> ore.ls()
[1] "AIRQUALITY"
R> 
R> # Save the proxy object and all objects in the current workspace environment
R> # to the datastore named ds1 and supply a description.
R> ore.save(AIRQUALITY, list = ls(), name = "ds1", description = "My datastore")
R> 
R> # Create some more objects.
R> x <- stats::runif(20)  # x is an object of type numeric.
R> y <- list(a = 1, b = TRUE, c = "hoopsa")
R> z <- ore.push(x)  # z is an object of type ore.numeric.
R> 
R> # Create another datastore.
R> ore.save(x, y, name = "ds2", description = "x and y")
R> 
R> # Overwrite the contents of datastore ds2.
R> ore.save(x, name = "ds2", overwrite = TRUE, description = "only x")
R> 
R> # Append object z to datastore ds2.
R> ore.save(z, name = "ds2", append = TRUE)

Parent topic: Save and Manage R Objects in the Database