ALTER TABLE DROP COLUMN works. Patch by Christopher Kings-Lynne,

code review by Tom Lane.  Remaining issues: functions that take or
return tuple types are likely to break if one drops (or adds!)
a column in the table defining the type.  Need to think about what
to do here.

Along the way: some code review for recent COPY changes; mark system
columns attnotnull = true where appropriate, per discussion a month ago.

4 files changed, 495 insertions, 9 deletions

diff --git a/src/test/regress/expected/alter_table.out b/src/test/regress/expected/alter_table.out
index 2dc64f3ccfa..741b012c289 100644
--- a/src/test/regress/expected/alter_table.out
+++ b/src/test/regress/expected/alter_table.out
@@ -635,9 +635,9 @@ delete from atacc1;
 alter table atacc1 alter test set not null;
 -- try altering a non-existent column, should fail
 alter table atacc1 alter bar set not null;
-ERROR:  ALTER TABLE: relation "atacc1" has no column "bar"
+ERROR:  Relation "atacc1" has no column "bar"
 alter table atacc1 alter bar drop not null;
-ERROR:  ALTER TABLE: relation "atacc1" has no column "bar"
+ERROR:  Relation "atacc1" has no column "bar"
 -- try altering the oid column, should fail
 alter table atacc1 alter oid set not null;
 ERROR:  ALTER TABLE: Cannot alter system attribute "oid"
@@ -707,7 +707,7 @@ ERROR:  pg_atoi: error in "wrong_datatype": can't parse "wrong_datatype"
 alter table def_test alter column c2 set default 20;
 -- set defaults on a non-existent column: this should fail
 alter table def_test alter column c3 set default 30;
-ERROR:  ALTER TABLE: relation "def_test" has no column "c3"
+ERROR:  Relation "def_test" has no column "c3"
 -- set defaults on views: we need to create a view, add a rule
 -- to allow insertions into it, and then alter the view to add
 -- a default
@@ -735,3 +735,291 @@ select * from def_view_test;
 drop rule def_view_test_ins on def_view_test;
 drop view def_view_test;
 drop table def_test;
+-- alter table / drop column tests
+-- try altering system catalogs, should fail
+alter table pg_class drop column relname;
+ERROR:  ALTER TABLE: relation "pg_class" is a system catalog
+-- try altering non-existent table, should fail
+alter table foo drop column bar;
+ERROR:  Relation "foo" does not exist
+-- test dropping columns
+create table atacc1 (a int4 not null, b int4, c int4 not null, d int4);
+insert into atacc1 values (1, 2, 3, 4);
+alter table atacc1 drop a;
+alter table atacc1 drop a;
+ERROR:  Relation "atacc1" has no column "a"
+-- SELECTs
+select * from atacc1;
+ b | c | d 
+---+---+---
+ 2 | 3 | 4
+(1 row)
+
+select * from atacc1 order by a;
+ERROR:  Attribute "a" not found
+select * from atacc1 order by "........pg.dropped.1........";
+ERROR:  Attribute "........pg.dropped.1........" not found
+select * from atacc1 group by a;
+ERROR:  Attribute "a" not found
+select * from atacc1 group by "........pg.dropped.1........";
+ERROR:  Attribute "........pg.dropped.1........" not found
+select atacc1.* from atacc1;
+ b | c | d 
+---+---+---
+ 2 | 3 | 4
+(1 row)
+
+select a from atacc1;
+ERROR:  Attribute "a" not found
+select atacc1.a from atacc1;
+ERROR:  No such attribute atacc1.a
+select b,c,d from atacc1;
+ b | c | d 
+---+---+---
+ 2 | 3 | 4
+(1 row)
+
+select a,b,c,d from atacc1;
+ERROR:  Attribute "a" not found
+select * from atacc1 where a = 1;
+ERROR:  Attribute "a" not found
+select "........pg.dropped.1........" from atacc1;
+ERROR:  Attribute "........pg.dropped.1........" not found
+select atacc1."........pg.dropped.1........" from atacc1;
+ERROR:  No such attribute atacc1.........pg.dropped.1........
+select "........pg.dropped.1........",b,c,d from atacc1;
+ERROR:  Attribute "........pg.dropped.1........" not found
+select * from atacc1 where "........pg.dropped.1........" = 1;
+ERROR:  Attribute "........pg.dropped.1........" not found
+-- UPDATEs
+update atacc1 set a = 3;
+ERROR:  Relation "atacc1" has no column "a"
+update atacc1 set b = 2 where a = 3;
+ERROR:  Attribute "a" not found
+update atacc1 set "........pg.dropped.1........" = 3;
+ERROR:  Relation "atacc1" has no column "........pg.dropped.1........"
+update atacc1 set b = 2 where "........pg.dropped.1........" = 3;
+ERROR:  Attribute "........pg.dropped.1........" not found
+-- INSERTs
+insert into atacc1 values (10, 11, 12, 13);
+ERROR:  INSERT has more expressions than target columns
+insert into atacc1 values (default, 11, 12, 13);
+ERROR:  INSERT has more expressions than target columns
+insert into atacc1 values (11, 12, 13);
+insert into atacc1 (a) values (10);
+ERROR:  Relation "atacc1" has no column "a"
+insert into atacc1 (a) values (default);
+ERROR:  Relation "atacc1" has no column "a"
+insert into atacc1 (a,b,c,d) values (10,11,12,13);
+ERROR:  Relation "atacc1" has no column "a"
+insert into atacc1 (a,b,c,d) values (default,11,12,13);
+ERROR:  Relation "atacc1" has no column "a"
+insert into atacc1 (b,c,d) values (11,12,13);
+insert into atacc1 ("........pg.dropped.1........") values (10);
+ERROR:  Relation "atacc1" has no column "........pg.dropped.1........"
+insert into atacc1 ("........pg.dropped.1........") values (default);
+ERROR:  Relation "atacc1" has no column "........pg.dropped.1........"
+insert into atacc1 ("........pg.dropped.1........",b,c,d) values (10,11,12,13);
+ERROR:  Relation "atacc1" has no column "........pg.dropped.1........"
+insert into atacc1 ("........pg.dropped.1........",b,c,d) values (default,11,12,13);
+ERROR:  Relation "atacc1" has no column "........pg.dropped.1........"
+-- DELETEs
+delete from atacc1 where a = 3;
+ERROR:  Attribute "a" not found
+delete from atacc1 where "........pg.dropped.1........" = 3;
+ERROR:  Attribute "........pg.dropped.1........" not found
+delete from atacc1;
+-- try dropping a non-existent column, should fail
+alter table atacc1 drop bar;
+ERROR:  Relation "atacc1" has no column "bar"
+-- try dropping the oid column, should fail
+alter table atacc1 drop oid;
+ERROR:  ALTER TABLE: Cannot drop system attribute "oid"
+-- try creating a view and altering that, should fail
+create view myview as select * from atacc1;
+select * from myview;
+ b | c | d 
+---+---+---
+(0 rows)
+
+alter table myview drop d;
+ERROR:  ALTER TABLE: relation "myview" is not a table
+drop view myview;
+-- test some commands to make sure they fail on the dropped column
+analyze atacc1(a);
+ERROR:  Relation "atacc1" has no column "a"
+analyze atacc1("........pg.dropped.1........");
+ERROR:  Relation "atacc1" has no column "........pg.dropped.1........"
+vacuum analyze atacc1(a);
+ERROR:  Relation "atacc1" has no column "a"
+vacuum analyze atacc1("........pg.dropped.1........");
+ERROR:  Relation "atacc1" has no column "........pg.dropped.1........"
+comment on column atacc1.a is 'testing';
+ERROR:  Relation "atacc1" has no column "a"
+comment on column atacc1."........pg.dropped.1........" is 'testing';
+ERROR:  Relation "atacc1" has no column "........pg.dropped.1........"
+alter table atacc1 alter a set storage plain;
+ERROR:  ALTER TABLE: relation "atacc1" has no column "a"
+alter table atacc1 alter "........pg.dropped.1........" set storage plain;
+ERROR:  ALTER TABLE: relation "atacc1" has no column "........pg.dropped.1........"
+alter table atacc1 alter a set statistics 0;
+ERROR:  ALTER TABLE: relation "atacc1" has no column "a"
+alter table atacc1 alter "........pg.dropped.1........" set statistics 0;
+ERROR:  ALTER TABLE: relation "atacc1" has no column "........pg.dropped.1........"
+alter table atacc1 alter a set default 3;
+ERROR:  Relation "atacc1" has no column "a"
+alter table atacc1 alter "........pg.dropped.1........" set default 3;
+ERROR:  Relation "atacc1" has no column "........pg.dropped.1........"
+alter table atacc1 alter a drop default;
+ERROR:  Relation "atacc1" has no column "a"
+alter table atacc1 alter "........pg.dropped.1........" drop default;
+ERROR:  Relation "atacc1" has no column "........pg.dropped.1........"
+alter table atacc1 alter a set not null;
+ERROR:  Relation "atacc1" has no column "a"
+alter table atacc1 alter "........pg.dropped.1........" set not null;
+ERROR:  Relation "atacc1" has no column "........pg.dropped.1........"
+alter table atacc1 alter a drop not null;
+ERROR:  Relation "atacc1" has no column "a"
+alter table atacc1 alter "........pg.dropped.1........" drop not null;
+ERROR:  Relation "atacc1" has no column "........pg.dropped.1........"
+alter table atacc1 rename a to x;
+ERROR:  renameatt: attribute "a" does not exist
+alter table atacc1 rename "........pg.dropped.1........" to x;
+ERROR:  renameatt: attribute "........pg.dropped.1........" does not exist
+alter table atacc1 add primary key(a);
+ERROR:  ALTER TABLE: column "a" named in key does not exist
+alter table atacc1 add primary key("........pg.dropped.1........");
+ERROR:  ALTER TABLE: column "........pg.dropped.1........" named in key does not exist
+alter table atacc1 add unique(a);
+ERROR:  ALTER TABLE: column "a" named in key does not exist
+alter table atacc1 add unique("........pg.dropped.1........");
+ERROR:  ALTER TABLE: column "........pg.dropped.1........" named in key does not exist
+alter table atacc1 add check (a > 3);
+ERROR:  Attribute "a" not found
+alter table atacc1 add check ("........pg.dropped.1........" > 3);
+ERROR:  Attribute "........pg.dropped.1........" not found
+create table atacc2 (id int4 unique);
+NOTICE:  CREATE TABLE / UNIQUE will create implicit index 'atacc2_id_key' for table 'atacc2'
+alter table atacc1 add foreign key (a) references atacc2(id);
+NOTICE:  ALTER TABLE will create implicit trigger(s) for FOREIGN KEY check(s)
+ERROR:  ALTER TABLE: column "a" referenced in foreign key constraint does not exist
+alter table atacc1 add foreign key ("........pg.dropped.1........") references atacc2(id);
+NOTICE:  ALTER TABLE will create implicit trigger(s) for FOREIGN KEY check(s)
+ERROR:  ALTER TABLE: column "........pg.dropped.1........" referenced in foreign key constraint does not exist
+alter table atacc2 add foreign key (id) references atacc1(a);
+NOTICE:  ALTER TABLE will create implicit trigger(s) for FOREIGN KEY check(s)
+ERROR:  UNIQUE constraint matching given keys for referenced table "atacc1" not found
+alter table atacc2 add foreign key (id) references atacc1("........pg.dropped.1........");
+NOTICE:  ALTER TABLE will create implicit trigger(s) for FOREIGN KEY check(s)
+ERROR:  UNIQUE constraint matching given keys for referenced table "atacc1" not found
+drop table atacc2;
+create index "testing_idx" on atacc1(a);
+ERROR:  DefineIndex: attribute "a" not found
+create index "testing_idx" on atacc1("........pg.dropped.1........");
+ERROR:  DefineIndex: attribute "........pg.dropped.1........" not found
+-- test create as and select into
+insert into atacc1 values (21, 22, 23);
+create table test1 as select * from atacc1;
+select * from test1;
+ b  | c  | d  
+----+----+----
+ 21 | 22 | 23
+(1 row)
+
+drop table test1;
+select * into test2 from atacc1;
+select * from test2;
+ b  | c  | d  
+----+----+----
+ 21 | 22 | 23
+(1 row)
+
+drop table test2;
+-- try dropping all columns
+alter table atacc1 drop c;
+alter table atacc1 drop d;
+alter table atacc1 drop b;
+ERROR:  ALTER TABLE: Cannot drop last column from table "atacc1"
+select * from atacc1;
+ b  
+----
+ 21
+(1 row)
+
+drop table atacc1;
+-- test inheritance
+create table parent (a int, b int, c int);
+insert into parent values (1, 2, 3);
+alter table parent drop a;
+create table child (d varchar(255)) inherits (parent);
+insert into child values (12, 13, 'testing');
+select * from parent;
+ b  | c  
+----+----
+  2 |  3
+ 12 | 13
+(2 rows)
+
+select * from child;
+ b  | c  |    d    
+----+----+---------
+ 12 | 13 | testing
+(1 row)
+
+alter table parent drop c;
+select * from parent;
+ b  
+----
+  2
+ 12
+(2 rows)
+
+select * from child;
+ b  |    d    
+----+---------
+ 12 | testing
+(1 row)
+
+drop table child;
+drop table parent;
+-- test copy in/out
+create table test (a int4, b int4, c int4);
+insert into test values (1,2,3);
+alter table test drop a;
+copy test to stdout;
+2	3
+copy test(a) to stdout;
+ERROR:  Relation "test" has no column "a"
+copy test("........pg.dropped.1........") to stdout;
+ERROR:  Relation "test" has no column "........pg.dropped.1........"
+copy test from stdin;
+ERROR:  copy: line 1, Extra data after last expected column
+lost synchronization with server, resetting connection
+select * from test;
+ b | c 
+---+---
+ 2 | 3
+(1 row)
+
+copy test from stdin;
+select * from test;
+ b  | c  
+----+----
+  2 |  3
+ 21 | 22
+(2 rows)
+
+copy test(a) from stdin;
+ERROR:  Relation "test" has no column "a"
+copy test("........pg.dropped.1........") from stdin;
+ERROR:  Relation "test" has no column "........pg.dropped.1........"
+copy test(b,c) from stdin;
+select * from test;
+ b  | c  
+----+----
+  2 |  3
+ 21 | 22
+ 31 | 32
+(3 rows)
+
+drop table test;
diff --git a/src/test/regress/expected/copy2.out b/src/test/regress/expected/copy2.out
index e4f806c8a56..58a5b6eb22a 100644
--- a/src/test/regress/expected/copy2.out
+++ b/src/test/regress/expected/copy2.out
@@ -29,26 +29,44 @@ COPY x (b, d) from stdin;
 COPY x (a, b, c, d, e) from stdin;
 -- non-existent column in column list: should fail
 COPY x (xyz) from stdin;
-ERROR:  COPY: Specified column "xyz" does not exist
+ERROR:  Relation "x" has no column "xyz"
 -- too many columns in column list: should fail
 COPY x (a, b, c, d, e, d, c) from stdin;
-ERROR:  COPY: Too many columns specified
+ERROR:  Attribute "d" specified more than once
 -- missing data: should fail
 COPY x from stdin;
-ERROR:  copy: line 1, COPY TEXT: Missing data for attribute 1
+ERROR:  copy: line 1, Missing data for column "b"
 lost synchronization with server, resetting connection
 COPY x from stdin;
-ERROR:  copy: line 1, COPY TEXT: Missing data for attribute 4
+ERROR:  copy: line 1, Missing data for column "e"
 lost synchronization with server, resetting connection
 COPY x from stdin;
-ERROR:  copy: line 1, COPY TEXT: Missing data for attribute 4
+ERROR:  copy: line 1, Missing data for column "e"
 lost synchronization with server, resetting connection
 -- extra data: should fail
 COPY x from stdin;
-ERROR:  copy: line 1, COPY TEXT: Extra data encountered
+ERROR:  copy: line 1, Extra data after last expected column
 lost synchronization with server, resetting connection
 -- various COPY options: delimiters, oids, NULL string
 COPY x (b, c, d, e) from stdin with oids delimiter ',' null 'x';
+-- check results of copy in
+SELECT * FROM x;
+   a   | b  |   c   |   d    |          e           
+-------+----+-------+--------+----------------------
+ 10000 | 21 | 31    | 41     | before trigger fired
+ 10001 | 22 | 32    | 42     | before trigger fired
+ 10002 | 23 | 33    | 43     | before trigger fired
+ 10003 | 24 | 34    | 44     | before trigger fired
+ 10004 | 25 | 35    | 45     | before trigger fired
+ 10005 | 26 | 36    | 46     | before trigger fired
+     6 |    | 45    | 80     | before trigger fired
+     1 |  1 | stuff | test_1 | after trigger fired
+     2 |  2 | stuff | test_2 | after trigger fired
+     3 |  3 | stuff | test_3 | after trigger fired
+     4 |  4 | stuff | test_4 | after trigger fired
+     5 |  5 | stuff | test_5 | after trigger fired
+(12 rows)
+
 -- COPY w/ oids on a table w/o oids should fail
 CREATE TABLE no_oids (
 	a	int,
@@ -61,6 +79,7 @@ COPY no_oids FROM stdin WITH OIDS;
 ERROR:  COPY: table "no_oids" does not have OIDs
 COPY no_oids TO stdout WITH OIDS;
 ERROR:  COPY: table "no_oids" does not have OIDs
+-- check copy out
 COPY x TO stdout;
 10000	21	31	41	before trigger fired
 10001	22	32	42	before trigger fired
@@ -87,6 +106,19 @@ stuff	after trigger fired
 stuff	after trigger fired
 stuff	after trigger fired
 stuff	after trigger fired
+COPY x (b, e) TO stdout WITH NULL 'I''m null';
+21	before trigger fired
+22	before trigger fired
+23	before trigger fired
+24	before trigger fired
+25	before trigger fired
+26	before trigger fired
+I'm null	before trigger fired
+1	after trigger fired
+2	after trigger fired
+3	after trigger fired
+4	after trigger fired
+5	after trigger fired
 DROP TABLE x;
 DROP FUNCTION fn_x_before();
 DROP FUNCTION fn_x_after();
diff --git a/src/test/regress/sql/alter_table.sql b/src/test/regress/sql/alter_table.sql
index f39998073d7..8946d2b15b3 100644
--- a/src/test/regress/sql/alter_table.sql
+++ b/src/test/regress/sql/alter_table.sql
@@ -571,3 +571,163 @@ select * from def_view_test;
 drop rule def_view_test_ins on def_view_test;
 drop view def_view_test;
 drop table def_test;
+
+-- alter table / drop column tests
+-- try altering system catalogs, should fail
+alter table pg_class drop column relname;
+
+-- try altering non-existent table, should fail
+alter table foo drop column bar;
+
+-- test dropping columns
+create table atacc1 (a int4 not null, b int4, c int4 not null, d int4);
+insert into atacc1 values (1, 2, 3, 4);
+alter table atacc1 drop a;
+alter table atacc1 drop a;
+
+-- SELECTs
+select * from atacc1;
+select * from atacc1 order by a;
+select * from atacc1 order by "........pg.dropped.1........";
+select * from atacc1 group by a;
+select * from atacc1 group by "........pg.dropped.1........";
+select atacc1.* from atacc1;
+select a from atacc1;
+select atacc1.a from atacc1;
+select b,c,d from atacc1;
+select a,b,c,d from atacc1;
+select * from atacc1 where a = 1;
+select "........pg.dropped.1........" from atacc1;
+select atacc1."........pg.dropped.1........" from atacc1;
+select "........pg.dropped.1........",b,c,d from atacc1;
+select * from atacc1 where "........pg.dropped.1........" = 1;
+
+-- UPDATEs
+update atacc1 set a = 3;
+update atacc1 set b = 2 where a = 3;
+update atacc1 set "........pg.dropped.1........" = 3;
+update atacc1 set b = 2 where "........pg.dropped.1........" = 3;
+
+-- INSERTs
+insert into atacc1 values (10, 11, 12, 13);
+insert into atacc1 values (default, 11, 12, 13);
+insert into atacc1 values (11, 12, 13);
+insert into atacc1 (a) values (10);
+insert into atacc1 (a) values (default);
+insert into atacc1 (a,b,c,d) values (10,11,12,13);
+insert into atacc1 (a,b,c,d) values (default,11,12,13);
+insert into atacc1 (b,c,d) values (11,12,13);
+insert into atacc1 ("........pg.dropped.1........") values (10);
+insert into atacc1 ("........pg.dropped.1........") values (default);
+insert into atacc1 ("........pg.dropped.1........",b,c,d) values (10,11,12,13);
+insert into atacc1 ("........pg.dropped.1........",b,c,d) values (default,11,12,13);
+
+-- DELETEs
+delete from atacc1 where a = 3;
+delete from atacc1 where "........pg.dropped.1........" = 3;
+delete from atacc1;
+
+-- try dropping a non-existent column, should fail
+alter table atacc1 drop bar;
+
+-- try dropping the oid column, should fail
+alter table atacc1 drop oid;
+
+-- try creating a view and altering that, should fail
+create view myview as select * from atacc1;
+select * from myview;
+alter table myview drop d;
+drop view myview;
+
+-- test some commands to make sure they fail on the dropped column
+analyze atacc1(a);
+analyze atacc1("........pg.dropped.1........");
+vacuum analyze atacc1(a);
+vacuum analyze atacc1("........pg.dropped.1........");
+comment on column atacc1.a is 'testing';
+comment on column atacc1."........pg.dropped.1........" is 'testing';
+alter table atacc1 alter a set storage plain;
+alter table atacc1 alter "........pg.dropped.1........" set storage plain;
+alter table atacc1 alter a set statistics 0;
+alter table atacc1 alter "........pg.dropped.1........" set statistics 0;
+alter table atacc1 alter a set default 3;
+alter table atacc1 alter "........pg.dropped.1........" set default 3;
+alter table atacc1 alter a drop default;
+alter table atacc1 alter "........pg.dropped.1........" drop default;
+alter table atacc1 alter a set not null;
+alter table atacc1 alter "........pg.dropped.1........" set not null;
+alter table atacc1 alter a drop not null;
+alter table atacc1 alter "........pg.dropped.1........" drop not null;
+alter table atacc1 rename a to x;
+alter table atacc1 rename "........pg.dropped.1........" to x;
+alter table atacc1 add primary key(a);
+alter table atacc1 add primary key("........pg.dropped.1........");
+alter table atacc1 add unique(a);
+alter table atacc1 add unique("........pg.dropped.1........");
+alter table atacc1 add check (a > 3);
+alter table atacc1 add check ("........pg.dropped.1........" > 3);
+create table atacc2 (id int4 unique);
+alter table atacc1 add foreign key (a) references atacc2(id);
+alter table atacc1 add foreign key ("........pg.dropped.1........") references atacc2(id);
+alter table atacc2 add foreign key (id) references atacc1(a);
+alter table atacc2 add foreign key (id) references atacc1("........pg.dropped.1........");
+drop table atacc2;
+create index "testing_idx" on atacc1(a);
+create index "testing_idx" on atacc1("........pg.dropped.1........");
+
+-- test create as and select into
+insert into atacc1 values (21, 22, 23);
+create table test1 as select * from atacc1;
+select * from test1;
+drop table test1;
+select * into test2 from atacc1;
+select * from test2;
+drop table test2;
+
+-- try dropping all columns
+alter table atacc1 drop c;
+alter table atacc1 drop d;
+alter table atacc1 drop b;
+select * from atacc1;
+
+drop table atacc1;
+
+-- test inheritance
+create table parent (a int, b int, c int);
+insert into parent values (1, 2, 3);
+alter table parent drop a;
+create table child (d varchar(255)) inherits (parent);
+insert into child values (12, 13, 'testing');
+
+select * from parent;
+select * from child;
+alter table parent drop c;
+select * from parent;
+select * from child;
+
+drop table child;
+drop table parent;
+
+-- test copy in/out
+create table test (a int4, b int4, c int4);
+insert into test values (1,2,3);
+alter table test drop a;
+copy test to stdout;
+copy test(a) to stdout;
+copy test("........pg.dropped.1........") to stdout;
+copy test from stdin;
+10	11	12
+\.
+select * from test;
+copy test from stdin;
+21	22
+\.
+select * from test;
+copy test(a) from stdin;
+copy test("........pg.dropped.1........") from stdin;
+copy test(b,c) from stdin;
+31	32
+\.
+select * from test;
+drop table test;
+
diff --git a/src/test/regress/sql/copy2.sql b/src/test/regress/sql/copy2.sql
index b0ccfe67160..4f0d50247f1 100644
--- a/src/test/regress/sql/copy2.sql
+++ b/src/test/regress/sql/copy2.sql
@@ -76,6 +76,9 @@ COPY x (b, c, d, e) from stdin with oids delimiter ',' null 'x';
 500000,x,45,80,90
 \.
 
+-- check results of copy in
+SELECT * FROM x;
+
 -- COPY w/ oids on a table w/o oids should fail
 CREATE TABLE no_oids (
 	a	int,
@@ -89,8 +92,11 @@ INSERT INTO no_oids (a, b) VALUES (20, 30);
 COPY no_oids FROM stdin WITH OIDS;
 COPY no_oids TO stdout WITH OIDS;
 
+-- check copy out
 COPY x TO stdout;
 COPY x (c, e) TO stdout;
+COPY x (b, e) TO stdout WITH NULL 'I''m null';
+
 DROP TABLE x;
 DROP FUNCTION fn_x_before();
 DROP FUNCTION fn_x_after();