Super-class for all results of [Prepared|Callable]Statement.XXXExecuteXXX()
commands that holds the sql warning chain generated by the execution of this
command.
In order to introduce the sql warnings support, every command issued on a
backend must call getWarnings() right after its execution. This is the only
way to keep the context and to make sure that no other command is issued
between the execute and the getWarnings.
Warnings are *not* retrieved by default, so there will be no performance
issue for those who don't need warnings. To enable them, use
"?retrieveSQLWarnings=true" URL option at connection time (this is a
by-connection property)
author: Gilles Rayrat version: 1.0
Get the warning chain associated to the current result
the warning chain or null if there were no warning, or if warningsretrieval was not enabled for this connection