Error on the query - Mailing list pgsql-general

Hi, ALL,
Trying to execute following query:

[code]
        queries.push_back( L"DO $$ BEGIN IF NOT EXISTS( SELECT 1 FROM
pg_class c, pg_namespace n WHERE n.oid = c.relnamespace AND c.relname
= \'abcatc_x\' AND n.nspname = \'public\' ) THEN CREATE UNIQUE INDEX
\"abcatc_x\" ON \"abcatcol\"(\"abc_tnam\" ASC, \"abc_ownr\" ASC,
\"abc_cnam\" ASC); END IF; END;" );
[/code]

I got:

[quote]
$4 = L"ERROR:  unterminated dollar-quoted string at or near \"$$ BEGIN
IF NOT EXISTS( SELECT 1 FROM pg_class c, pg_namespace n WHERE n.oid =
c.relnamespace AND c.relna
me = 'abcatc_x' AND n.nspname = 'public' "...

[/quote]

What am I missing?

Thank you.