safe.write {RSQLite}R Documentation

Write a data.frame avoiding exceeding memory limits

Description

This function batches calls to write.table to avoid exceeding memory limits for very large data.frames.

Usage

safe.write(value, file, batch, row.names = TRUE, ..., sep = ',', 
  eol = '\n', quote.string=FALSE)

Arguments

value a data.frame;
file a file object (connection, file name, etc).
batch maximum number of rows to write at a time.
... any other arguments are passed to write.table.
sep field separator passed to write.table.
eol end of line character passed to write.table.
quote.string logical value passed to write.table.

Details

The function has a while loop invoking write.table for subsets of batch rows of value. Since this is a helper function for mysqlWriteTable has hardcoded other arguments to write.table.

Value

NULL, invisibly.

Note

No error checking whatsoever is done.

See Also

write.table

Examples

## Not run: 
   ctr.file <- file("dump.sqloader", "w")
   safe.write(big.data, file = ctr.file, batch = 25000)
## End(Not run)

[Package RSQLite version 0.6-9 Index]