(5 rows)
-- another sort of polymorphic aggregate
-CREATE AGGREGATE array_cat_accum (anyarray)
+CREATE AGGREGATE array_larger_accum (anyarray)
(
- sfunc = array_cat,
+ sfunc = array_larger,
stype = anyarray,
initcond = '{}'
);
-SELECT array_cat_accum(i)
+SELECT array_larger_accum(i)
FROM (VALUES (ARRAY[1,2]), (ARRAY[3,4])) as t(i);
- array_cat_accum
------------------
- {1,2,3,4}
+ array_larger_accum
+--------------------
+ {3,4}
(1 row)
-SELECT array_cat_accum(i)
+SELECT array_larger_accum(i)
FROM (VALUES (ARRAY[row(1,2),row(3,4)]), (ARRAY[row(5,6),row(7,8)])) as t(i);
- array_cat_accum
------------------------------------
- {"(1,2)","(3,4)","(5,6)","(7,8)"}
+ array_larger_accum
+--------------------
+ {"(5,6)","(7,8)"}
(1 row)
-- another kind of polymorphic aggregate
STYPE = int8[]
);
-- check proper resolution of data types for polymorphic transfn/finalfn
+create function first_el_transfn(anyarray, anyelement) returns anyarray as
+'select $1 || $2' language sql immutable;
create function first_el(anyarray) returns anyelement as
'select $1[1]' language sql strict immutable;
create aggregate first_el_agg_f8(float8) (
FINALFUNC = first_el
);
create aggregate first_el_agg_any(anyelement) (
- SFUNC = array_append,
+ SFUNC = first_el_transfn,
STYPE = anyarray,
FINALFUNC = first_el
);
-- another sort of polymorphic aggregate
-CREATE AGGREGATE array_cat_accum (anyarray)
+CREATE AGGREGATE array_larger_accum (anyarray)
(
- sfunc = array_cat,
+ sfunc = array_larger,
stype = anyarray,
initcond = '{}'
);
-SELECT array_cat_accum(i)
+SELECT array_larger_accum(i)
FROM (VALUES (ARRAY[1,2]), (ARRAY[3,4])) as t(i);
-SELECT array_cat_accum(i)
+SELECT array_larger_accum(i)
FROM (VALUES (ARRAY[row(1,2),row(3,4)]), (ARRAY[row(5,6),row(7,8)])) as t(i);
-- another kind of polymorphic aggregate
-- check proper resolution of data types for polymorphic transfn/finalfn
+create function first_el_transfn(anyarray, anyelement) returns anyarray as
+'select $1 || $2' language sql immutable;
+
create function first_el(anyarray) returns anyelement as
'select $1[1]' language sql strict immutable;
);
create aggregate first_el_agg_any(anyelement) (
- SFUNC = array_append,
+ SFUNC = first_el_transfn,
STYPE = anyarray,
FINALFUNC = first_el
);