laketablecmds: case-normalize the USING format; use base_path in the …

…volume example

- gram.y: lower-case the USING format for the access method name (it was only
  upper-cased for table_type), so a quoted "ICEBERG" / "IceBerg" resolves the
  iceberg AM instead of failing late with "access method ... does not exist".
- regress: add a quoted mixed-case format case to lock this in; rename the
  volume path option in the example from `path` to `base_path` to match the
  agreed name (discussion #1683).  Volume options are free-form (no validator),
  so this is example-only.
- create_foreign_volume.sgml: same base_path example.

doc/src/sgml/ref/create_foreign_volume.sgml

@@ -107,7 +107,7 @@ CREATE FOREIGN VOLUME [ IF NOT EXISTS ] <replaceable class="parameter">volume_na
    Create a volume for an object storage prefix using the foreign server
    <literal>s3_srv</literal>:
 <programlisting>
-CREATE FOREIGN VOLUME s3_vol SERVER s3_srv OPTIONS (path 's3://bucket/prefix');
+CREATE FOREIGN VOLUME s3_vol SERVER s3_srv OPTIONS (base_path 's3://bucket/prefix');
 </programlisting></para>
  </refsect1>
 

src/backend/parser/gram.y

@@ -9188,10 +9188,19 @@ CreateLakeTableStmt:
 				{
 					CreateLakeTableStmt *n = makeNode(CreateLakeTableStmt);
 					char	   *table_type = pstrdup($9);
+					char	   *access_method = pstrdup($9);
 					char	   *p;
 
+					/*
+					 * The USING format is case-insensitive: upper-case it for
+					 * the stored table_type and lower-case it for the access
+					 * method name, so a quoted "ICEBERG" resolves the same AM
+					 * as an unquoted iceberg.
+					 */
 					for (p = table_type; *p; p++)
 						*p = pg_toupper((unsigned char) *p);
+					for (p = access_method; *p; p++)
+						*p = pg_tolower((unsigned char) *p);
 
 					$4->relpersistence = RELPERSISTENCE_PERMANENT;
 					n->base.relation = $4;
@@ -9202,7 +9211,7 @@ CreateLakeTableStmt:
 					n->base.options = NIL;
 					n->base.oncommit = ONCOMMIT_NOOP;
 					n->base.tablespacename = NULL;
-					n->base.accessMethod = $9;
+					n->base.accessMethod = access_method;
 					n->base.if_not_exists = false;
 					n->base.relKind = RELKIND_RELATION;
 					n->table_type = table_type;
@@ -9226,10 +9235,19 @@ CreateLakeTableStmt:
 				{
 					CreateLakeTableStmt *n = makeNode(CreateLakeTableStmt);
 					char	   *table_type = pstrdup($12);
+					char	   *access_method = pstrdup($12);
 					char	   *p;
 
+					/*
+					 * The USING format is case-insensitive: upper-case it for
+					 * the stored table_type and lower-case it for the access
+					 * method name, so a quoted "ICEBERG" resolves the same AM
+					 * as an unquoted iceberg.
+					 */
 					for (p = table_type; *p; p++)
 						*p = pg_toupper((unsigned char) *p);
+					for (p = access_method; *p; p++)
+						*p = pg_tolower((unsigned char) *p);
 
 					$7->relpersistence = RELPERSISTENCE_PERMANENT;
 					n->base.relation = $7;
@@ -9240,7 +9258,7 @@ CreateLakeTableStmt:
 					n->base.options = NIL;
 					n->base.oncommit = ONCOMMIT_NOOP;
 					n->base.tablespacename = NULL;
-					n->base.accessMethod = $12;
+					n->base.accessMethod = access_method;
 					n->base.if_not_exists = true;
 					n->base.relKind = RELKIND_RELATION;
 					n->table_type = table_type;

src/test/regress/expected/lake_table.out

@@ -69,7 +69,7 @@ SELECT fcname, fctype, fcoptions FROM pg_foreign_catalog WHERE fcname LIKE 'lake
 (1 row)
 
 -- CREATE FOREIGN VOLUME
-CREATE FOREIGN VOLUME lake_test_vol SERVER lake_test_srv OPTIONS (path 's3://bucket/prefix');
+CREATE FOREIGN VOLUME lake_test_vol SERVER lake_test_srv OPTIONS (base_path 's3://bucket/prefix');
 CREATE FOREIGN VOLUME lake_test_vol SERVER lake_test_srv;			-- fail, duplicate
 ERROR:  foreign volume "lake_test_vol" already exists
 CREATE FOREIGN VOLUME IF NOT EXISTS lake_test_vol SERVER lake_test_srv;	-- skip with notice
@@ -82,9 +82,9 @@ NOTICE:  foreign volume "lake_test_vol" already exists, skipping
 CREATE FOREIGN VOLUME lake_test_bad SERVER no_such_server;			-- fail, no server
 ERROR:  server "no_such_server" does not exist
 SELECT fvname, fvoptions FROM pg_foreign_volume WHERE fvname LIKE 'lake\_test%';
-    fvname     |         fvoptions         
----------------+---------------------------
- lake_test_vol | {path=s3://bucket/prefix}
+    fvname     |           fvoptions            
+---------------+--------------------------------
+ lake_test_vol | {base_path=s3://bucket/prefix}
 (1 row)
 
 -- Object descriptions
@@ -203,7 +203,7 @@ SELECT policytype, distkey FROM gp_distribution_policy WHERE localoid = 'lake_te
 CREATE LAKE TABLE lake_test_bad0 (a int) USING heap CATALOG lake_test_cat VOLUME lake_test_vol;		-- fail, unsupported format
 ERROR:  unsupported lake table format "HEAP"
 HINT:  The only supported format is ICEBERG (USING ICEBERG).
-CREATE LAKE TABLE lake_test_t4 (a int) USING iceberg CATALOG lake_test_cat VOLUME lake_test_vol;	-- lower-case format is fine
+CREATE LAKE TABLE lake_test_t4 (a int) USING "IceBerg" CATALOG lake_test_cat VOLUME lake_test_vol;	-- quoted mixed-case format resolves the iceberg AM
 -- The iceberg AM is rejected for every path other than CREATE LAKE TABLE
 CREATE TABLE lake_test_bad1 (a int) USING iceberg DISTRIBUTED RANDOMLY;			-- fail
 ERROR:  cannot create table "lake_test_bad1" with access method "iceberg"

src/test/regress/sql/lake_table.sql

@@ -24,7 +24,7 @@ CREATE FOREIGN CATALOG lake_test_bad SERVER no_such_server TYPE 'hive';		-- fail
 SELECT fcname, fctype, fcoptions FROM pg_foreign_catalog WHERE fcname LIKE 'lake\_test%';
 
 -- CREATE FOREIGN VOLUME
-CREATE FOREIGN VOLUME lake_test_vol SERVER lake_test_srv OPTIONS (path 's3://bucket/prefix');
+CREATE FOREIGN VOLUME lake_test_vol SERVER lake_test_srv OPTIONS (base_path 's3://bucket/prefix');
 CREATE FOREIGN VOLUME lake_test_vol SERVER lake_test_srv;			-- fail, duplicate
 CREATE FOREIGN VOLUME IF NOT EXISTS lake_test_vol SERVER lake_test_srv;	-- skip with notice
 -- volume names are global: the same name on another server is still a duplicate
@@ -92,7 +92,7 @@ SELECT policytype, distkey FROM gp_distribution_policy WHERE localoid = 'lake_te
 
 -- The USING clause names the table format; only ICEBERG is supported (any case)
 CREATE LAKE TABLE lake_test_bad0 (a int) USING heap CATALOG lake_test_cat VOLUME lake_test_vol;		-- fail, unsupported format
-CREATE LAKE TABLE lake_test_t4 (a int) USING iceberg CATALOG lake_test_cat VOLUME lake_test_vol;	-- lower-case format is fine
+CREATE LAKE TABLE lake_test_t4 (a int) USING "IceBerg" CATALOG lake_test_cat VOLUME lake_test_vol;	-- quoted mixed-case format resolves the iceberg AM
 
 -- The iceberg AM is rejected for every path other than CREATE LAKE TABLE
 CREATE TABLE lake_test_bad1 (a int) USING iceberg DISTRIBUTED RANDOMLY;			-- fail