Adjust naming of indexes and their columns per recent discussion.

Index expression columns are now named after the FigureColname result for
their expressions, rather than always being "pg_expression_N".  Digits are
appended to this name if needed to make the column name unique within the
index.  (That happens for regular columns too, thus fixing the old problem
that CREATE INDEX fooi ON foo (f1, f1) fails.  Before exclusion indexes
there was no real reason to do such a thing, but now maybe there is.)

Default names for indexes and associated constraints now include the column
names of all their columns, not only the first one as in previous practice.
(Of course, this will be truncated as needed to fit in NAMEDATALEN.  Also,
pkey indexes retain the historical behavior of not naming specific columns
at all.)

An example of the results:

regression=# create table foo (f1 int, f2 text,
regression(# exclude (f1 with =, lower(f2) with =));
NOTICE:  CREATE TABLE / EXCLUDE will create implicit index "foo_f1_lower_exclusion" for table "foo"
CREATE TABLE
regression=# \d foo_f1_lower_exclusion
Index "public.foo_f1_lower_exclusion"
 Column |  Type   | Definition
--------+---------+------------
 f1     | integer | f1
 lower  | text    | lower(f2)
btree, for table "public.foo"

4 files changed, 13 insertions, 13 deletions

diff --git a/src/test/regress/expected/alter_table.out b/src/test/regress/expected/alter_table.out
index 20bf3de3bad..5aff44f23aa 100644
--- a/src/test/regress/expected/alter_table.out
+++ b/src/test/regress/expected/alter_table.out
@@ -159,7 +159,7 @@ CREATE TABLE tmp2 (a int primary key);
 NOTICE:  CREATE TABLE / PRIMARY KEY will create implicit index "tmp2_pkey" for table "tmp2"
 CREATE TABLE tmp3 (a int, b int);
 CREATE TABLE tmp4 (a int, b int, unique(a,b));
-NOTICE:  CREATE TABLE / UNIQUE will create implicit index "tmp4_a_key" for table "tmp4"
+NOTICE:  CREATE TABLE / UNIQUE will create implicit index "tmp4_a_b_key" for table "tmp4"
 CREATE TABLE tmp5 (a int, b int);
 -- Insert rows into tmp2 (pktable)
 INSERT INTO tmp2 values (1);
diff --git a/src/test/regress/expected/foreign_key.out b/src/test/regress/expected/foreign_key.out
index 33e0edba03a..0367f532337 100644
--- a/src/test/regress/expected/foreign_key.out
+++ b/src/test/regress/expected/foreign_key.out
@@ -736,7 +736,7 @@ ERROR:  table "fktable_fail2" does not exist
 DROP TABLE PKTABLE;
 -- Test for referencing column number smaller than referenced constraint
 CREATE TABLE PKTABLE (ptest1 int, ptest2 int, UNIQUE(ptest1, ptest2));
-NOTICE:  CREATE TABLE / UNIQUE will create implicit index "pktable_ptest1_key" for table "pktable"
+NOTICE:  CREATE TABLE / UNIQUE will create implicit index "pktable_ptest1_ptest2_key" for table "pktable"
 CREATE TABLE FKTABLE_FAIL1 (ftest1 int REFERENCES pktable(ptest1));
 ERROR:  there is no unique constraint matching given keys for referenced table "pktable"
 DROP TABLE FKTABLE_FAIL1;
@@ -860,7 +860,7 @@ DETAIL:  Key columns "ptest4" and "ptest1" are of incompatible types: inet and i
 create table pktable_base (base1 int not null);
 create table pktable (ptest1 int, primary key(base1), unique(base1, ptest1)) inherits (pktable_base);
 NOTICE:  CREATE TABLE / PRIMARY KEY will create implicit index "pktable_pkey" for table "pktable"
-NOTICE:  CREATE TABLE / UNIQUE will create implicit index "pktable_base1_key" for table "pktable"
+NOTICE:  CREATE TABLE / UNIQUE will create implicit index "pktable_base1_ptest1_key" for table "pktable"
 create table fktable (ftest1 int references pktable(base1));
 -- now some ins, upd, del
 insert into pktable(base1) values (1);
@@ -1098,7 +1098,7 @@ CREATE TEMP TABLE pktable (
 NOTICE:  CREATE TABLE / PRIMARY KEY will create implicit index "pktable_pkey" for table "pktable"
 NOTICE:  CREATE TABLE / UNIQUE will create implicit index "pktable_id2_key" for table "pktable"
 NOTICE:  CREATE TABLE / UNIQUE will create implicit index "pktable_id3_key" for table "pktable"
-NOTICE:  CREATE TABLE / UNIQUE will create implicit index "pktable_id1_key" for table "pktable"
+NOTICE:  CREATE TABLE / UNIQUE will create implicit index "pktable_id1_id2_id3_key" for table "pktable"
 CREATE TEMP TABLE fktable (
         x1      INT4 REFERENCES pktable(id1),
         x2      VARCHAR(4) REFERENCES pktable(id2),
diff --git a/src/test/regress/expected/inherit.out b/src/test/regress/expected/inherit.out
index aa1eb4a4ddb..9c83a32f934 100644
--- a/src/test/regress/expected/inherit.out
+++ b/src/test/regress/expected/inherit.out
@@ -1031,8 +1031,8 @@ NOTICE:  CREATE TABLE / PRIMARY KEY will create implicit index "t_all_pkey" for
  b      | text |           | extended | B
 Indexes:
     "t_all_pkey" PRIMARY KEY, btree (a)
-    "t_all_b_key" btree (b)
-    "t_all_key" btree ((a || b))
+    "t_all_b_idx" btree (b)
+    "t_all_expr_idx" btree ((a || b))
 Check constraints:
     "t1_a_check" CHECK (length(a) > 2)
 Has OIDs: no
@@ -1040,7 +1040,7 @@ Has OIDs: no
 SELECT c.relname, objsubid, description FROM pg_description, pg_index i, pg_class c WHERE classoid = 'pg_class'::regclass AND objoid = i.indexrelid AND c.oid = i.indexrelid AND i.indrelid = 't_all'::regclass ORDER BY c.relname, objsubid;
    relname   | objsubid | description 
 -------------+----------+-------------
- t_all_b_key |        0 | index b_key
+ t_all_b_idx |        0 | index b_key
  t_all_pkey  |        0 | index pkey
 (2 rows)
 
diff --git a/src/test/regress/output/constraints.source b/src/test/regress/output/constraints.source
index 8928ca8beba..684394fd83d 100644
--- a/src/test/regress/output/constraints.source
+++ b/src/test/regress/output/constraints.source
@@ -359,12 +359,12 @@ SELECT '' AS five, * FROM UNIQUE_TBL;
 DROP TABLE UNIQUE_TBL;
 CREATE TABLE UNIQUE_TBL (i int, t text,
 	UNIQUE(i,t));
-NOTICE:  CREATE TABLE / UNIQUE will create implicit index "unique_tbl_i_key" for table "unique_tbl"
+NOTICE:  CREATE TABLE / UNIQUE will create implicit index "unique_tbl_i_t_key" for table "unique_tbl"
 INSERT INTO UNIQUE_TBL VALUES (1, 'one');
 INSERT INTO UNIQUE_TBL VALUES (2, 'two');
 INSERT INTO UNIQUE_TBL VALUES (1, 'three');
 INSERT INTO UNIQUE_TBL VALUES (1, 'one');
-ERROR:  duplicate key value violates unique constraint "unique_tbl_i_key"
+ERROR:  duplicate key value violates unique constraint "unique_tbl_i_t_key"
 DETAIL:  Key (i, t)=(1, one) already exists.
 INSERT INTO UNIQUE_TBL VALUES (5, 'one');
 INSERT INTO UNIQUE_TBL (t) VALUES ('six');
@@ -523,7 +523,7 @@ CREATE TABLE circles (
     (c1 WITH &&, (c2::circle) WITH ~=)
     WHERE (circle_center(c1) <> '(0,0)')
 );
-NOTICE:  CREATE TABLE / EXCLUDE will create implicit index "circles_c1_exclusion" for table "circles"
+NOTICE:  CREATE TABLE / EXCLUDE will create implicit index "circles_c1_c2_exclusion" for table "circles"
 -- these should succeed because they don't match the index predicate
 INSERT INTO circles VALUES('<(0,0), 5>', '<(0,0), 5>');
 INSERT INTO circles VALUES('<(0,0), 5>', '<(0,0), 5>');
@@ -531,7 +531,7 @@ INSERT INTO circles VALUES('<(0,0), 5>', '<(0,0), 5>');
 INSERT INTO circles VALUES('<(10,10), 10>', '<(0,0), 5>');
 -- fail, overlaps
 INSERT INTO circles VALUES('<(20,20), 10>', '<(0,0), 5>');
-ERROR:  conflicting key value violates exclusion constraint "circles_c1_exclusion"
+ERROR:  conflicting key value violates exclusion constraint "circles_c1_c2_exclusion"
 DETAIL:  Key (c1, (c2::circle))=(<(20,20),10>, <(0,0),5>) conflicts with existing key (c1, (c2::circle))=(<(10,10),10>, <(0,0),5>).
 -- succeed because c1 doesn't overlap
 INSERT INTO circles VALUES('<(20,20), 1>', '<(0,0), 5>');
@@ -540,8 +540,8 @@ INSERT INTO circles VALUES('<(20,20), 10>', '<(1,1), 5>');
 -- should fail on existing data without the WHERE clause
 ALTER TABLE circles ADD EXCLUDE USING gist
   (c1 WITH &&, (c2::circle) WITH ~=);
-NOTICE:  ALTER TABLE / ADD EXCLUDE will create implicit index "circles_c1_exclusion1" for table "circles"
-ERROR:  could not create exclusion constraint "circles_c1_exclusion1"
+NOTICE:  ALTER TABLE / ADD EXCLUDE will create implicit index "circles_c1_c2_exclusion1" for table "circles"
+ERROR:  could not create exclusion constraint "circles_c1_c2_exclusion1"
 DETAIL:  Key (c1, (c2::circle))=(<(0,0),5>, <(0,0),5>) conflicts with key (c1, (c2::circle))=(<(0,0),5>, <(0,0),5>).
 DROP TABLE circles;
 -- Check deferred exclusion constraint