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pbdDEMO (version 0.2-0)

read.sql.ddmatrix: A Simple Parallel SQL Reader

Description

Read in a table from a SQL database in parallel as a distributed matrix.

Usage

read.sql.ddmatrix(dbname, table, bldim = .BLDIM, num.rdrs = 1, ICTXT = 0)

Arguments

dbname
database name
table
name of the table from dbname to be read
bldim
the blocking dimension for block-cyclically distributing the matrix across the process grid
num.rdrs
numer of processes to be used to read in the table
ICTXT
BLACS context number for return

Value

  • Returns a distributed matrix.

Details

The function reads in data from a SQL database using the sqldf package into a distributed matrix. It operates at a 'bare bones' level, in that it will be assumed that the table desired to be read in 'looks' very much like a matrix. That is, it assumes that the table is basically just a csv-like structure that has been stowed away in a database.