Newbie, Howto access Array-Slots in user defined functions?

Hi,

I am new to this list, maybe my question is already answered, but
I did not find any hint.

I have PostgreSQL 6.3 running, a table contains, among others, a
column with an array of bytes (c bytea[4]). Trying to do a

    SELECT DISTINCT c FROM table;

I get

ERROR:  There is no operator '<' for types '_bytea' and '_bytea'
        You will either have to retype this query using an explicit cast,
        or you will have to define the operator using CREATE OPERATOR

To create an operator I need a function, so let's beginn with a
compare function:

    CREATE FUNCTION lessbyte (_bytea, _bytea) RETURNS bool AS
    'SELECT $1[1] < $[2];' LANGUAGE 'sql';

I get

    ERROR:  parser: parse error at or near "["

Any hint, how to overcome this?

Martin

--
Martin Jacobs * Windsbach * 100.179370@germanynet.de und
martin.jacobs@an-netz.de
Registered Linux User #87175