[jira] Commented: (DERBY-2902) AS IDENTITY (START WITH -9223372036854775808) fails

["Bryan Pendleton (JIRA)" <ji...@apache.org>]

    [ https://issues.apache.org/jira/browse/DERBY-2902?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel#action_12510368 ] 

Bryan Pendleton commented on DERBY-2902:
----------------------------------------

I think the problem is indeed in the parser. It appears that the minus sign is
treated as a separate token in the tokenization of the expression, and the
value is converted to a Long, then the minus sign is applied to convert the long
to a negative number. There is the following code in SQLParser's exactNumber()
method:

                        long longvalue = Long.parseLong(longToken.image);
                        if (sign.equals("-"))
                        {
                                {if (true) return -longvalue;}
                        }
                        else
                        {
                                {if (true) return longvalue;}
                        }

Since Long.MAX_VALUE is 9223372036854775807, while
Long.MIN_VALUE is -9223372036854775808, we cannot successfully
parse Long.MIN_VALUE because we try to do it by first computing
Long.parseLong(9223372036854775808), which exceeds Long.MAX_VALUE
and hence throws the exception.

One approach might be to try replacing the above code in exactNumber()
by something like:

                        if (sign.equals("-"))
                        {
                                return Long.parseLong("-" + longToken.image);
                        }
                        else
                        {
                                return Long.parseLong(longToken.image);
                        }

If I get some spare time this weekend I'll give that a try.



> AS IDENTITY (START WITH -9223372036854775808) fails
> ---------------------------------------------------
>
>                 Key: DERBY-2902
>                 URL: https://issues.apache.org/jira/browse/DERBY-2902
>             Project: Derby
>          Issue Type: Bug
>          Components: SQL
>    Affects Versions: 10.2.2.0
>         Environment: MacTel 10.4.10 JVM 1.6.0-dp
>            Reporter: James Alan Shepherd
>            Priority: Minor
>
> When creating a table
> AS IDENTITY (START WITH -9223372036854775808)
> fails but
> AS IDENTITY (START WITH -9223372036854775807)
> succeeds.
> Guess this is a parsing SQL problem as the absolute value appears to be held in a long, which is not quite long enough at the positive end.

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