replace_matches does not return {null}

Hi,

I tried to order a text-column only by parts of the entries. Therefore I used regexp_matches(), but unfortunately I am loosing rows.

SELECT regexp_matches('abc','[0-9]+'), regexp_matches('123','[0-9]+');

Does not return "{null}, {123}" but no result at all.

Is this behavior expected? How can I work around?

I am running postgres 8.4

Andreas

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SCANLAB AG
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Entwicklung * R & D

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