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From Abraham Elmahrek <...@cloudera.com>
Subject Re: Null values and escaping
Date Sat, 04 Jan 2014 00:46:57 GMT
Hey There,

Have you tried the --null-string option? See
http://sqoop.apache.org/docs/1.4.4/SqoopUserGuide.html#idp3491496 for more
details. It should change null string values to what ever string you
specify.

-Abe


On Fri, Jan 3, 2014 at 4:34 AM, redshift-etl-user <redshift.etl@gmail.com>wrote:

> I'm importing from a DB into a text file, and I need to distinguish
> between null and non-null strings. Is there a combination of parameters
> (i.e. escaped-by, enclosed-by, and null-string) that yields unambiguous
> output strings? With the default options "null-string" is "null", and so
> there's no way of distinguishing between a null string and the string
> "null" in the output file.
>
> One solution to this would be to avoid escaping the specified null string.
> That way we could specify "escaped-by" as "\" and "null-string" as "\N" and
> get "\N" in the output as opposed to "\\N" for null strings. That way it's
> guaranteed to be different from any non-null string.
>
> In the generated code's toString() method this would mean changing from
>
> __sb.append(FieldFormatter.escapeAndEnclose(STRING==null?"\\N":STRING,
> delimiters));
>
> to
>
> __sb.append(STRING==null?"\\N":FieldFormatter.escapeAndEnclose(STRING,
> delimiters));
>
> Thoughts? Any ideas for a workaround?
>
>  Thanks!
>

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