Merge #40812

40812: sql: another syntax hint for ALTER PARTITION r=solongordon a=solongordon

If a user tries to specify an index in ALTER PARTITION ... OF TABLE,
they now receive a hint to use ALTER PARTITION ... OF INDEX instead.

I added similar logic recently but only for the index wildcard syntax,
<tablename>@*.

Release justification: Low-risk error messaging improvement

Release note: None

Co-authored-by: Solon Gordon <solon@cockroachlabs.com>

pkg/sql/parser/parse_test.go

@@ -2683,6 +2683,14 @@ DETAIL: source SQL:
 CREATE STATISTICS a ON col1 FROM t WITH OPTIONS AS OF SYSTEM TIME '-1s' THROTTLING 0.1 AS OF SYSTEM TIME '-2s'
                                                                                                               ^`,
 		},
+		{
+			`ALTER PARTITION p OF TABLE tbl@idx CONFIGURE ZONE USING num_replicas = 1`,
+			`at or near "idx": syntax error: index name should not be specified in ALTER PARTITION ... OF TABLE
+DETAIL: source SQL:
+ALTER PARTITION p OF TABLE tbl@idx CONFIGURE ZONE USING num_replicas = 1
+                               ^
+HINT: try ALTER PARTITION ... OF INDEX`,
+		},
 		{
 			`ALTER PARTITION p OF TABLE tbl@* CONFIGURE ZONE USING num_replicas = 1`,
 			`at or near "configure": syntax error: index wildcard unsupported in ALTER PARTITION ... OF TABLE

pkg/sql/parser/sql.y

@@ -1505,6 +1505,12 @@ alter_zone_partition_stmt:
     s.AllIndexes = true
     $$.val = s
   }
+| ALTER PARTITION partition_name OF TABLE table_name '@' error
+  {
+    err := errors.New("index name should not be specified in ALTER PARTITION ... OF TABLE")
+    err = errors.WithHint(err, "try ALTER PARTITION ... OF INDEX")
+    return setErr(sqllex, err)
+  }
 | ALTER PARTITION partition_name OF TABLE table_name '@' '*' error
   {
     err := errors.New("index wildcard unsupported in ALTER PARTITION ... OF TABLE")