IMPROVED VERSION APPLIED:

The attached patch completes the following TODO item:

    * Generate failure on short COPY lines rather than pad NULLs

I also restructed a lot of the existing COPY code, did some code
review on the column list patch sent in by Brent Verner a little
while ago, and added some regression tests. I also added an
explicit check (and resultant error) for extra data before
the end-of-line.

Neil Conway

doc/src/sgml/ref/copy.sgml

 <!--
-$Header: /cvsroot/pgsql/doc/src/sgml/ref/copy.sgml,v 1.33 2002/07/18 04:43:50 momjian Exp $
+$Header: /cvsroot/pgsql/doc/src/sgml/ref/copy.sgml,v 1.34 2002/07/30 16:55:05 momjian Exp $
 PostgreSQL documentation
 -->
 
@@ -199,12 +199,12 @@ ERROR: <replaceable>reason</replaceable>
    whatever is in the table already).
   </para>
 
-	<para>
-   When using the optional column list syntax, <command>COPY TO</command> 
-	 and <command>COPY FROM</command> will only copy the specified
-	 columns' values to/from the table. If a column in the table
-	 is not in the column list, <command>COPY FROM</command> will insert 
-	 default values for that column if a default value is defined.
+  <para>
+   If a list of columns is specified, <command>COPY</command> will
+   only copy the data in the specified columns to or from the table.
+   If there are any columns in the table that are not in the table,
+   <command>COPY FROM</command> will insert the default value for
+   that column.
   </para>
 
   <para>
@@ -266,8 +266,8 @@ ERROR: <replaceable>reason</replaceable>
    </para>
 
    <para>
-    <command>COPY FROM</command> neither invokes rules nor acts on column
-    defaults.  It does invoke triggers and check constraints.
+    <command>COPY FROM</command> will invoke any triggers or check
+	constraints. However, it will not invoke rules.
    </para>
 
    <para>
@@ -330,7 +330,12 @@ ERROR: <replaceable>reason</replaceable>
     The attribute values themselves are strings generated by the
     output function, or acceptable to the input function, of each
     attribute's data type.  The specified null-value string is used in
-    place of attributes that are NULL.
+    place of attributes that are NULL.  When using <command>COPY
+	FROM</command> without a column list, each row of the input file
+	must contain data for each attribute in the table: no missing data
+	is allowed.  Similarly, <command>COPY FROM</command> will raise
+	an error if it encounters any data in the input file that would
+	not be inserted into the table: extra data is not allowed.
    </para>
    <para>
     If OIDS is specified, the OID is read or written as the first column,

src/test/regress/expected/copy2.out

@@ -23,10 +23,44 @@ CREATE TRIGGER trg_x_after AFTER INSERT ON x
 FOR EACH ROW EXECUTE PROCEDURE fn_x_after();
 CREATE TRIGGER trg_x_before BEFORE INSERT ON x
 FOR EACH ROW EXECUTE PROCEDURE fn_x_before();
-COPY x (a,b,c,d,e) from stdin;
-COPY x (b,d) from stdin;
-COPY x (b,d) from stdin;
-COPY x (a,b,c,d,e) from stdin;
+COPY x (a, b, c, d, e) from stdin;
+COPY x (b, d) from stdin;
+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
+-- 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
+-- missing data: should fail
+COPY x from stdin;
+ERROR:  copy: line 1, COPY TEXT: Missing data for attribute 1
+lost synchronization with server, resetting connection
+COPY x from stdin;
+ERROR:  copy: line 1, COPY TEXT: Missing data for attribute 4
+lost synchronization with server, resetting connection
+COPY x from stdin;
+ERROR:  copy: line 1, COPY TEXT: Missing data for attribute 4
+lost synchronization with server, resetting connection
+-- extra data: should fail
+COPY x from stdin;
+ERROR:  copy: line 1, COPY TEXT: Extra data encountered
+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';
+-- COPY w/ oids on a table w/o oids should fail
+CREATE TABLE no_oids (
+	a	int,
+	b	int
+) WITHOUT OIDS;
+INSERT INTO no_oids (a, b) VALUES (5, 10);
+INSERT INTO no_oids (a, b) VALUES (20, 30);
+-- should fail
+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
 COPY x TO stdout;
 10000	21	31	41	before trigger fired
 10001	22	32	42	before trigger fired
@@ -34,11 +68,25 @@ COPY x TO stdout;
 10003	24	34	44	before trigger fired
 10004	25	35	45	before trigger fired
 10005	26	36	46	before trigger fired
+6	\N	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
+COPY x (c, e) TO stdout;
+31	before trigger fired
+32	before trigger fired
+33	before trigger fired
+34	before trigger fired
+35	before trigger fired
+36	before trigger fired
+45	before trigger fired
+stuff	after trigger fired
+stuff	after trigger fired
+stuff	after trigger fired
+stuff	after trigger fired
+stuff	after trigger fired
 DROP TABLE x;
 DROP FUNCTION fn_x_before();
 DROP FUNCTION fn_x_after();

src/test/regress/sql/copy2.sql

@@ -26,22 +26,22 @@ FOR EACH ROW EXECUTE PROCEDURE fn_x_after();
 CREATE TRIGGER trg_x_before BEFORE INSERT ON x
 FOR EACH ROW EXECUTE PROCEDURE fn_x_before();
 
-COPY x (a,b,c,d,e) from stdin;
+COPY x (a, b, c, d, e) from stdin;
 10000	21	31	41	51
 \.
 
-COPY x (b,d) from stdin;
+COPY x (b, d) from stdin;
 1	test_1
 \.
 
-COPY x (b,d) from stdin;
+COPY x (b, d) from stdin;
 2	test_2
 3	test_3
 4	test_4
 5	test_5
 \.
 
-COPY x (a,b,c,d,e) from stdin;
+COPY x (a, b, c, d, e) from stdin;
 10001	22	32	42	52
 10002	23	33	43	53
 10003	24	34	44	54
@@ -49,7 +49,48 @@ COPY x (a,b,c,d,e) from stdin;
 10005	26	36	46	56
 \.
 
+-- non-existent column in column list: should fail
+COPY x (xyz) from stdin;
+
+-- too many columns in column list: should fail
+COPY x (a, b, c, d, e, d, c) from stdin;
+
+-- missing data: should fail
+COPY x from stdin;
+
+\.
+COPY x from stdin;
+2000	230	23	23
+\.
+COPY x from stdin;
+2001	231	\N	\N
+\.
+
+-- extra data: should fail
+COPY x from stdin;
+2002	232	40	50	60	70	80
+\.
+
+-- various COPY options: delimiters, oids, NULL string
+COPY x (b, c, d, e) from stdin with oids delimiter ',' null 'x';
+500000,x,45,80,90
+\.
+
+-- COPY w/ oids on a table w/o oids should fail
+CREATE TABLE no_oids (
+	a	int,
+	b	int
+) WITHOUT OIDS;
+
+INSERT INTO no_oids (a, b) VALUES (5, 10);
+INSERT INTO no_oids (a, b) VALUES (20, 30);
+
+-- should fail
+COPY no_oids FROM stdin WITH OIDS;
+COPY no_oids TO stdout WITH OIDS;
+
 COPY x TO stdout;
+COPY x (c, e) TO stdout;
 DROP TABLE x;
 DROP FUNCTION fn_x_before();
 DROP FUNCTION fn_x_after();