CONVERSION_ERROR option behavior change [CR 380625]

When the CONVERSION_ERROR option is set OFF, each thread doing data conversion for a LOAD statement now writes at most one warning message to the .iqmsg file.

In order to write all data conversion warning messages to the.iqmsg file, you must set the CONVERSION_ERROR OFF, then set the DDL_OPTIONS2 option to 8. For example:

SET TEMPORARY OPTION CONVERSION_ERROR='OFF'
SET TEMPORARY OPTION DDL_OPTIONS2=8