[R-sig-DB] [R] SQLite: When reading a table, a "\r" is padded onto the last column. Why?

[Seth Falcon]

ronggui <ronggui.huang using gmail.com> writes:

> On 1/6/07, Seth Falcon <sfalcon using fhcrc.org> wrote:
>> I wonder if things have changed at all in that regard.  I would expect
>> read.table to be slower, but, if called carefully, not _extremely_
>> slower.  We should do some timings...
>
> Yeah, Things change a lot.
> I use system.time to do the timings on a large csv file (365M, with
> sep="\t", quote="")
>
> The result is as follow:
> 1, use read.table and then dbWriteTable in chunck.
>> t1
> [1] 700.22  16.06 768.01     NA     NA

Can you provide the exact call to read.table you used?  

To give it a fair chance, you need to use the colClasses arg in
read.table and choose a reasonable batch size (I think the buffer
hard-coded in the RSQLite C code is 1024, so to compare you should
choose a number of rows that is ~1MB).

+ seth