Need help with EXECUTE function

Folks (esp Jan, Tom & Michael):

I have a search function I'm testing, which uses the EXECUTE function to
perform a dynamic set of string comparisons according to whcih criteria
the user passes along. Unfortunately, this requires me to triple-nest
my quotes .... and I can't seem to get it right. No matter how I play
with the function, it keeps blowing up due to "unterminated strings".
This happens even if I terminate the function short of the EXECUTE
statement.

Can someone *please* give me some pointers?

Function text:

create function fn_search_orders ( INT4, VARCHAR, INT2, VARCHAR, DATE,
VARCHAR,
INT4, INT4, VARCHAR, VARCHAR, INT4 )
RETURNS int4 AS '
DECLARE
v_client ALIAS for $1;
v_clname ALIAS for $2;
v_status ALIAS for $3;
v_datesearch ALIAS for $4;
v_start ALIAS for $5;
v_address ALIAS for $6;
v_contact ALIAS for $7;
v_staff_usq ALIAS for $8;
v_staff_name ALIAS for $9;
v_temps ALIAS for $10;
v_temp_usq ALIAS for $11;
search_id INT4;
query_string VARCHAR;
where_string VARCHAR;
search_count INT4;
BEGIN
search_id := NEXTVAL(''search_sq'');
query_string := ''INSERT INTO searches ( search_sq, usq ) SELECT '' ||
CAST(search_id AS VARCHAR)
|| '', usq FROM sv_orders WHERE '';
where_string := '''';
IF v_client > 0 THEN
where_string := '' AND client_usq = '' || CAST(v_client AS varchar);
END IF;
IF trim(v_clname) <> '''' THEN
where_string := where_string || '' AND client_name ~* '''''''' ||
v_clname ||
'''''';
END IF;
IF v_status <> 0 THEN
where_string := where_string || '' AND status = '' || CAST(v_status AS
VARCHAR);
ELSE
where_string := where_string || '' AND status > 0'';
END IF;
IF v_start > ''1950-01-01''::DATE THEN
IF v_datesearch = ''BEFORE'' THEN
where_string := where_string || '' AND start_date < '''''''' ||
to_char(v_start, ''YYYY-MM-DD'') || '''''';
ELSE
where_string := where_string || '' AND start_date > '''''''' ||
to_char(v_start,
''YYYY-MM-DD'') || '''''';
END IF;
END IF;
IF trim(v_address) <> '''' THEN
where_string := where_string || '' AND order_address ~* '''''''' ||
v_address
|| '''''';
END IF;
IF v_staff_usq > 0 THEN
where_string := where_string || '' AND resp_staff_usq = '' ||
CAST(v_staff_usq AS VARCHAR);
END IF;
IF trim(v_staff) <> '''' THEN
where_string := where_string || '' AND staff_name ~* '''''''' ||
v_staff ||
'''''';
END IF;
IF trim(v_contact) <> '''' THEN
where_string := where_string || '' AND order_contact ~* '''''''' ||
v_contact
|| '''''';
END IF;
IF trim(v_temps) <> '''' THEN
where_string := where_string || '' AND list_temps ~* '''''''' ||
v_temps ||
'''''';
END IF;
IF v_temp_usq > 0 THEN
where_string := where_string || '' AND usq IN(SELECT order_usq FROM
assignments WHERE candidate_usq = '' || CAST(v_temp_usq AS VARCHAR) ||
'')'';
END IF;
where_string := substr(where_string, 5);

EXECUTE query_string || where_string;
SELECT count(*) INTO search_count
FROM searches WHERE search_sq = search_id;
IF search_count > 0 THEN
RETURN search_id;
ELSE
RETURN 0;
END IF;
END;'
LANGUAGE 'plpgsql';

-Josh Berkus

______AGLIO DATABASE SOLUTIONS___________________________
Josh Berkus
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