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Rearrange ALTER TABLE syntax processing as per my recent proposal: the
grammar allows ALTER TABLE/INDEX/SEQUENCE/VIEW interchangeably for all subforms of those commands, and then we sort out what's really legal at execution time. This allows the ALTER SEQUENCE/VIEW reference pages to fully document all the ALTER forms available for sequences and views respectively, and eliminates a longstanding cause of confusion for users. The net effect is that the following forms are allowed that weren't before: ALTER SEQUENCE OWNER TO ALTER VIEW ALTER COLUMN SET/DROP DEFAULT ALTER VIEW OWNER TO ALTER VIEW SET SCHEMA (There's no actual functionality gain here, but formerly you had to say ALTER TABLE instead.) Interestingly, the grammar tables actually get smaller, probably because there are fewer special cases to keep track of. I did not disallow using ALTER TABLE for these operations. Perhaps we should, but there's a backwards-compatibility issue if we do; in fact it would break existing pg_dump scripts. I did however tighten up ALTER SEQUENCE and ALTER VIEW to reject non-sequences and non-views in the new cases as well as a couple of cases where they didn't before. The patch doesn't change pg_dump to use the new syntaxes, either.
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‎doc/src/sgml/ref/alter_sequence.sgml

+23-8
Original file line numberDiff line numberDiff line change
@@ -1,5 +1,5 @@
11
<!--
2-
$PostgreSQL: pgsql/doc/src/sgml/ref/alter_sequence.sgml,v 1.21 2008/05/17 01:20:39 tgl Exp $
2+
$PostgreSQL: pgsql/doc/src/sgml/ref/alter_sequence.sgml,v 1.22 2008/06/15 01:25:53 tgl Exp $
33
PostgreSQL documentation
44
-->
55

@@ -30,6 +30,7 @@ ALTER SEQUENCE <replaceable class="parameter">name</replaceable> [ INCREMENT [ B
3030
[ RESTART [ [ WITH ] <replaceable class="parameter">restart</replaceable> ] ]
3131
[ CACHE <replaceable class="parameter">cache</replaceable> ] [ [ NO ] CYCLE ]
3232
[ OWNED BY { <replaceable class="parameter">table</replaceable>.<replaceable class="parameter">column</replaceable> | NONE } ]
33+
ALTER SEQUENCE <replaceable class="parameter">name</replaceable> OWNER TO <replaceable class="PARAMETER">new_owner</replaceable>
3334
ALTER SEQUENCE <replaceable class="parameter">name</replaceable> RENAME TO <replaceable class="parameter">new_name</replaceable>
3435
ALTER SEQUENCE <replaceable class="parameter">name</replaceable> SET SCHEMA <replaceable class="parameter">new_schema</replaceable>
3536
</synopsis>
@@ -48,6 +49,11 @@ ALTER SEQUENCE <replaceable class="parameter">name</replaceable> SET SCHEMA <rep
4849
You must own the sequence to use <command>ALTER SEQUENCE</>.
4950
To change a sequence's schema, you must also have <literal>CREATE</>
5051
privilege on the new schema.
52+
To alter the owner, you must also be a direct or indirect member of the new
53+
owning role, and that role must have <literal>CREATE</literal> privilege on
54+
the sequence's schema. (These restrictions enforce that altering the owner
55+
doesn't do anything you couldn't do by dropping and recreating the sequence.
56+
However, a superuser can alter ownership of any sequence anyway.)
5157
</para>
5258
</refsect1>
5359

@@ -205,6 +211,15 @@ ALTER SEQUENCE <replaceable class="parameter">name</replaceable> SET SCHEMA <rep
205211
</listitem>
206212
</varlistentry>
207213

214+
<varlistentry>
215+
<term><replaceable class="PARAMETER">new_owner</replaceable></term>
216+
<listitem>
217+
<para>
218+
The user name of the new owner of the sequence.
219+
</para>
220+
</listitem>
221+
</varlistentry>
222+
208223
<varlistentry>
209224
<term><replaceable class="parameter">new_name</replaceable></term>
210225
<listitem>
@@ -233,9 +248,9 @@ ALTER SEQUENCE <replaceable class="parameter">name</replaceable> SET SCHEMA <rep
233248
<para>
234249
To avoid blocking of concurrent transactions that obtain numbers from the
235250
same sequence, <command>ALTER SEQUENCE</command>'s effects on the sequence
236-
generation parameters are never rolled back;
237-
those changes take effect immediately and are not reversible. However,
238-
the <literal>OWNED BY</>, <literal>RENAME</>, and <literal>SET SCHEMA</>
251+
generation parameters are never rolled back; those changes take effect
252+
immediately and are not reversible. However, the <literal>OWNED BY</>,
253+
<literal>OWNER TO</>, <literal>RENAME TO</>, and <literal>SET SCHEMA</>
239254
clauses cause ordinary catalog updates that can be rolled back.
240255
</para>
241256

@@ -255,9 +270,9 @@ ALTER SEQUENCE <replaceable class="parameter">name</replaceable> SET SCHEMA <rep
255270
</para>
256271

257272
<para>
258-
Some variants of <command>ALTER TABLE</command> can be used with
259-
sequences as well; for example, to rename a sequence it is also
260-
possible to use <command>ALTER TABLE RENAME</command>.
273+
For historical reasons, <command>ALTER TABLE</command> can be used with
274+
sequences too; but the only variants of <command>ALTER TABLE</command>
275+
that are allowed with sequences are equivalent to the forms shown above.
261276
</para>
262277
</refsect1>
263278

@@ -278,7 +293,7 @@ ALTER SEQUENCE serial RESTART WITH 105;
278293
<para>
279294
<command>ALTER SEQUENCE</command> conforms to the <acronym>SQL</acronym>
280295
standard, except for the <literal>START WITH</>,
281-
<literal>OWNED BY</>, <literal>RENAME</>, and
296+
<literal>OWNED BY</>, <literal>OWNER TO</>, <literal>RENAME TO</>, and
282297
<literal>SET SCHEMA</literal> clauses, which are
283298
<productname>PostgreSQL</productname> extensions.
284299
</para>

‎doc/src/sgml/ref/alter_view.sgml

+56-12
Original file line numberDiff line numberDiff line change
@@ -1,5 +1,5 @@
11
<!--
2-
$PostgreSQL: pgsql/doc/src/sgml/ref/alter_view.sgml,v 1.3 2007/10/03 16:48:43 tgl Exp $
2+
$PostgreSQL: pgsql/doc/src/sgml/ref/alter_view.sgml,v 1.4 2008/06/15 01:25:53 tgl Exp $
33
PostgreSQL documentation
44
-->
55

@@ -20,17 +20,32 @@ PostgreSQL documentation
2020

2121
<refsynopsisdiv>
2222
<synopsis>
23-
ALTER VIEW <replaceable>name</replaceable> RENAME TO <replaceable>newname</replaceable>
23+
ALTER VIEW <replaceable class="parameter">name</replaceable> ALTER [ COLUMN ] <replaceable class="PARAMETER">column</replaceable> SET DEFAULT <replaceable class="PARAMETER">expression</replaceable>
24+
ALTER VIEW <replaceable class="parameter">name</replaceable> ALTER [ COLUMN ] <replaceable class="PARAMETER">column</replaceable> DROP DEFAULT
25+
ALTER VIEW <replaceable class="parameter">name</replaceable> OWNER TO <replaceable class="PARAMETER">new_owner</replaceable>
26+
ALTER VIEW <replaceable class="parameter">name</replaceable> RENAME TO <replaceable class="parameter">new_name</replaceable>
27+
ALTER VIEW <replaceable class="parameter">name</replaceable> SET SCHEMA <replaceable class="parameter">new_schema</replaceable>
2428
</synopsis>
2529
</refsynopsisdiv>
2630

2731
<refsect1>
2832
<title>Description</title>
2933

3034
<para>
31-
<command>ALTER VIEW</command> changes the definition of a view.
32-
The only currently available functionality is to rename the view.
33-
To execute this command you must be the owner of the view.
35+
<command>ALTER VIEW</command> changes various auxiliary properties
36+
of a view. (If you want to modify the view's defining query,
37+
use <command>CREATE OR REPLACE VIEW</>.)
38+
</para>
39+
40+
<para>
41+
You must own the view to use <command>ALTER VIEW</>.
42+
To change a view's schema, you must also have <literal>CREATE</>
43+
privilege on the new schema.
44+
To alter the owner, you must also be a direct or indirect member of the new
45+
owning role, and that role must have <literal>CREATE</literal> privilege on
46+
the view's schema. (These restrictions enforce that altering the owner
47+
doesn't do anything you couldn't do by dropping and recreating the view.
48+
However, a superuser can alter ownership of any view anyway.)
3449
</para>
3550
</refsect1>
3651

@@ -48,10 +63,41 @@ ALTER VIEW <replaceable>name</replaceable> RENAME TO <replaceable>newname</repla
4863
</varlistentry>
4964

5065
<varlistentry>
51-
<term><replaceable class="parameter">newname</replaceable></term>
66+
<term><literal>SET</literal>/<literal>DROP DEFAULT</literal></term>
67+
<listitem>
68+
<para>
69+
These forms set or remove the default value for a column.
70+
A default value associated with a view column is
71+
inserted into <command>INSERT</> statements on the view before
72+
the view's <literal>ON INSERT</literal> rule is applied, if
73+
the <command>INSERT</> does not specify a value for the column.
74+
</para>
75+
</listitem>
76+
</varlistentry>
77+
78+
<varlistentry>
79+
<term><replaceable class="PARAMETER">new_owner</replaceable></term>
80+
<listitem>
81+
<para>
82+
The user name of the new owner of the view.
83+
</para>
84+
</listitem>
85+
</varlistentry>
86+
87+
<varlistentry>
88+
<term><replaceable class="parameter">new_name</replaceable></term>
89+
<listitem>
90+
<para>
91+
The new name for the view.
92+
</para>
93+
</listitem>
94+
</varlistentry>
95+
96+
<varlistentry>
97+
<term><replaceable class="parameter">new_schema</replaceable></term>
5298
<listitem>
5399
<para>
54-
The new name of the view.
100+
The new schema for the view.
55101
</para>
56102
</listitem>
57103
</varlistentry>
@@ -62,11 +108,9 @@ ALTER VIEW <replaceable>name</replaceable> RENAME TO <replaceable>newname</repla
62108
<title>Notes</title>
63109

64110
<para>
65-
Some variants of <command>ALTER TABLE</command> can be used with
66-
views as well; for example, to rename a view it is also
67-
possible to use <command>ALTER TABLE RENAME</command>. To change
68-
the schema or owner of a view, you currently must use <command>ALTER
69-
TABLE</>.
111+
For historical reasons, <command>ALTER TABLE</command> can be used with
112+
views too; but the only variants of <command>ALTER TABLE</command>
113+
that are allowed with views are equivalent to the ones shown above.
70114
</para>
71115
</refsect1>
72116

‎src/backend/commands/alter.c

+4-2
Original file line numberDiff line numberDiff line change
@@ -8,7 +8,7 @@
88
*
99
*
1010
* IDENTIFICATION
11-
* $PostgreSQL: pgsql/src/backend/commands/alter.c,v 1.28 2008/03/19 18:38:30 tgl Exp $
11+
* $PostgreSQL: pgsql/src/backend/commands/alter.c,v 1.29 2008/06/15 01:25:53 tgl Exp $
1212
*
1313
*-------------------------------------------------------------------------
1414
*/
@@ -185,8 +185,10 @@ ExecAlterObjectSchemaStmt(AlterObjectSchemaStmt *stmt)
185185

186186
case OBJECT_SEQUENCE:
187187
case OBJECT_TABLE:
188+
case OBJECT_VIEW:
188189
CheckRelationOwnership(stmt->relation, true);
189-
AlterTableNamespace(stmt->relation, stmt->newschema);
190+
AlterTableNamespace(stmt->relation, stmt->newschema,
191+
stmt->objectType);
190192
break;
191193

192194
case OBJECT_TYPE:

‎src/backend/commands/tablecmds.c

+71-2
Original file line numberDiff line numberDiff line change
@@ -8,7 +8,7 @@
88
*
99
*
1010
* IDENTIFICATION
11-
* $PostgreSQL: pgsql/src/backend/commands/tablecmds.c,v 1.256 2008/06/14 18:04:33 tgl Exp $
11+
* $PostgreSQL: pgsql/src/backend/commands/tablecmds.c,v 1.257 2008/06/15 01:25:53 tgl Exp $
1212
*
1313
*-------------------------------------------------------------------------
1414
*/
@@ -2175,6 +2175,44 @@ AlterTable(AlterTableStmt *stmt)
21752175

21762176
CheckTableNotInUse(rel, "ALTER TABLE");
21772177

2178+
/* Check relation type against type specified in the ALTER command */
2179+
switch (stmt->relkind)
2180+
{
2181+
case OBJECT_TABLE:
2182+
/*
2183+
* For mostly-historical reasons, we allow ALTER TABLE to apply
2184+
* to all relation types.
2185+
*/
2186+
break;
2187+
2188+
case OBJECT_INDEX:
2189+
if (rel->rd_rel->relkind != RELKIND_INDEX)
2190+
ereport(ERROR,
2191+
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
2192+
errmsg("\"%s\" is not an index",
2193+
RelationGetRelationName(rel))));
2194+
break;
2195+
2196+
case OBJECT_SEQUENCE:
2197+
if (rel->rd_rel->relkind != RELKIND_SEQUENCE)
2198+
ereport(ERROR,
2199+
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
2200+
errmsg("\"%s\" is not a sequence",
2201+
RelationGetRelationName(rel))));
2202+
break;
2203+
2204+
case OBJECT_VIEW:
2205+
if (rel->rd_rel->relkind != RELKIND_VIEW)
2206+
ereport(ERROR,
2207+
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
2208+
errmsg("\"%s\" is not a view",
2209+
RelationGetRelationName(rel))));
2210+
break;
2211+
2212+
default:
2213+
elog(ERROR, "unrecognized object type: %d", (int) stmt->relkind);
2214+
}
2215+
21782216
ATController(rel, stmt->cmds, interpretInhOption(stmt->relation->inhOpt));
21792217
}
21802218

@@ -7191,7 +7229,8 @@ ATExecDropInherit(Relation rel, RangeVar *parent)
71917229
* Note: caller must have checked ownership of the relation already
71927230
*/
71937231
void
7194-
AlterTableNamespace(RangeVar *relation, const char *newschema)
7232+
AlterTableNamespace(RangeVar *relation, const char *newschema,
7233+
ObjectType stmttype)
71957234
{
71967235
Relation rel;
71977236
Oid relid;
@@ -7204,6 +7243,36 @@ AlterTableNamespace(RangeVar *relation, const char *newschema)
72047243
relid = RelationGetRelid(rel);
72057244
oldNspOid = RelationGetNamespace(rel);
72067245

7246+
/* Check relation type against type specified in the ALTER command */
7247+
switch (stmttype)
7248+
{
7249+
case OBJECT_TABLE:
7250+
/*
7251+
* For mostly-historical reasons, we allow ALTER TABLE to apply
7252+
* to all relation types.
7253+
*/
7254+
break;
7255+
7256+
case OBJECT_SEQUENCE:
7257+
if (rel->rd_rel->relkind != RELKIND_SEQUENCE)
7258+
ereport(ERROR,
7259+
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
7260+
errmsg("\"%s\" is not a sequence",
7261+
RelationGetRelationName(rel))));
7262+
break;
7263+
7264+
case OBJECT_VIEW:
7265+
if (rel->rd_rel->relkind != RELKIND_VIEW)
7266+
ereport(ERROR,
7267+
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
7268+
errmsg("\"%s\" is not a view",
7269+
RelationGetRelationName(rel))));
7270+
break;
7271+
7272+
default:
7273+
elog(ERROR, "unrecognized object type: %d", (int) stmttype);
7274+
}
7275+
72077276
/* Can we change the schema of this tuple? */
72087277
switch (rel->rd_rel->relkind)
72097278
{

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