Allow a fix for #249 #267
Merged
Allow a fix for #249 #267
Conversation
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
From some research discovered [here](http://datamining.togaware.com/survivor/Database_Connection.html) and in the Netezza ODBC documentation [here](https://www.ibm.com/support/knowledgecenter/SSULQD_7.1.0/com.ibm.nz.datacon.doc/r_datacon_odbc_driver_setup_win.html), the Netezza ODBC driver, by default, has a 'Prefetch Count' setting, defaulting to 256, that limits the # of rows that will return for a resultset. It's unclear whether you can set this number to -1 or some really large integer # (4 trillion or so) and if that would work (or try to consume that much memory by pre-allocating?). In any case, RODBC has a setting `believeNRows`, so we introduce a similar (though IMO better named) keyword argument `ignore_driver_row_count`, which, when set to `true`, will force the result handling code to iterate rows with no known length, which is the setting we want when we're unable to pre-allocate full columns.
Codecov Report
@@ Coverage Diff @@
## master #267 +/- ##
=======================================
Coverage 72.19% 72.19%
=======================================
Files 5 5
Lines 651 651
=======================================
Hits 470 470
Misses 181 181
Continue to review full report at Codecov.
|
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
From some research discovered
here
and in the Netezza ODBC documentation
here,
the Netezza ODBC driver, by default, has a 'Prefetch Count' setting,
defaulting to 256, that limits the # of rows that will return for a
resultset. It's unclear whether you can set this number to -1 or some
really large integer # (4 trillion or so) and if that would work (or try
to consume that much memory by pre-allocating?).
In any case, RODBC has a setting
believeNRows, so we introduce asimilar (though IMO better named) keyword argument
ignore_driver_row_count, which, when set totrue, will force theresult handling code to iterate rows with no known length, which is the
setting we want when we're unable to pre-allocate full columns.