Aggregate data

Aggregate some data from the DataSHIELD R session using a valid R expression. The aggregation expression must satisfy the data repository's DataSHIELD configuration.

# S4 method for OpalConnection
dsAggregate(conn, expr, async = TRUE)

Arguments

conn

OpalConnection-class object.

expr

Expression to evaluate.

async

Whether the result of the call should be retrieved asynchronously. When TRUE (default) the calls are parallelized over the connections, when the connection supports that feature, with an extra overhead of requests.

Examples

if (FALSE) {
con <- dbConnect(DSOpal::Opal(), "username", "password", "https://opal.example.org")
dsAssignTable(con, "D", "test.CNSIM")
dsAggregate(con, as.symbol("meanDS(D$WEIGHT)"))
dsDisconnect(con)
}