[vtk-developers] [VTK 0013705]: vtkMySQLQuery incorrectly returning non NULL values in certain circumstances

[Mantis Bug Tracker]

The following issue has been SUBMITTED. 
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http://www.vtk.org/Bug/view.php?id=13705 
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Reported By:                Patrick Emond
Assigned To:                
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Project:                    VTK
Issue ID:                   13705
Category:                   (No Category)
Reproducibility:            have not tried
Severity:                   minor
Priority:                   normal
Status:                     backlog
Project:                    TBD 
Type:                       incorrect functionality 
Resolution:                 open
Fixed in Version:           
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Date Submitted:             2012-12-05 17:22 EST
Last Modified:              2012-12-05 17:22 EST
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Summary:                    vtkMySQLQuery incorrectly returning non NULL values
in certain circumstances
Description: 
When querying a table which has columns which may be null this class returns
non-null values when it shouldn't.  For instance, for the table:

CREATE TABLE myTable (
  myIntValue int DEFAULT NULL,
  myFloatValue float DEFAULT NULL
)

columns myIntValue and myFloatValue may be set to null, but when reading these
values using vtkMySQLQuery the values 0 and 0.0 are returned instead of NULL.

The reason is found in vtkMySQLQuery::DataValue  Specifically, in the switch
statement there are several return statements which do the following:

return vtkVariant(base.ToInt());

When the value is NULL the variable "base" is correctly set to an un-initialized
state.  Calling ToInt() returns 0 even if it is not a valid number (NULL), so
instead this line should read:

return base.IsValid() ? vtkVariant(base.ToInt()) : base;

The same could be applied for long, floats and doubles.
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Issue History 
Date Modified    Username       Field                    Change               
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2012-12-05 17:22 Patrick Emond  New Issue                                    
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