Reduce calls to GetTableMetadata endpoint; Never search catalog for Function entries

src/include/storage/iceberg_table_information.hpp

@@ -45,11 +45,12 @@ struct IcebergTableInformation {
 	IRCSchemaEntry &schema;
 	string name;
 	string table_id;
-	// bool deleted;
 
 	rest_api_objects::LoadTableResult load_table_result;
 	IcebergTableMetadata table_metadata;
 	unordered_map<int32_t, unique_ptr<ICTableEntry>> schema_versions;
+	// dummy entry to hold existence of a table, but no schema versions
+	unique_ptr<ICTableEntry> dummy_entry;
 
 public:
 	unique_ptr<IcebergTransactionData> transaction_data;

src/include/storage/irc_catalog.hpp

@@ -48,6 +48,17 @@ class IRCatalog : public Catalog {
 	bool SetCachedValue(const string &url, const string &value, const rest_api_objects::LoadTableResult &result);
 	static void SetAWSCatalogOptions(IcebergAttachOptions &attach_options,
 	                                 case_insensitive_set_t &set_by_attach_options);
+	//! Whether or not this catalog should search a specific type with the standard priority
+	CatalogLookupBehavior CatalogTypeLookupRule(CatalogType type) const override {
+		switch (type) {
+		case CatalogType::TABLE_FUNCTION_ENTRY:
+		case CatalogType::SCALAR_FUNCTION_ENTRY:
+		case CatalogType::AGGREGATE_FUNCTION_ENTRY:
+			return CatalogLookupBehavior::NEVER_LOOKUP;
+		default:
+			return CatalogLookupBehavior::STANDARD;
+		}
+	}
 
 public:
 	static unique_ptr<Catalog> Attach(optional_ptr<StorageExtensionInfo> storage_info, ClientContext &context,

src/storage/irc_table_set.cpp

@@ -31,7 +31,6 @@ ICTableSet::ICTableSet(IRCSchemaEntry &schema) : schema(schema), catalog(schema.
 
 bool ICTableSet::FillEntry(ClientContext &context, IcebergTableInformation &table) {
 	if (!table.schema_versions.empty()) {
-		//! Already filled
 		return true;
 	}
 
@@ -67,13 +66,31 @@ void ICTableSet::Scan(ClientContext &context, const std::function<void(CatalogEn
 	auto table_namespace = IRCAPI::GetEncodedSchemaName(schema.namespace_items);
 	for (auto &entry : entries) {
 		auto &table_info = entry.second;
-		if (FillEntry(context, table_info)) {
-			auto schema_id = table_info.table_metadata.current_schema_id;
-			callback(*table_info.schema_versions[schema_id]);
-		} else {
-			DUCKDB_LOG(context, IcebergLogType, "Table %s.%s not an Iceberg Table", table_namespace, entry.first);
-			non_iceberg_tables.insert(entry.first);
+		if (table_info.dummy_entry) {
+			// FIXME: why do we need to return the same entry again?
+			auto &optional = table_info.dummy_entry.get()->Cast<CatalogEntry>();
+			callback(optional);
+			continue;
 		}
+
+		// create a table entry with fake schema data to avoid calling the LoadTableInformation endpoint for every
+		// table while listing schemas
+		CreateTableInfo info(schema, table_info.name);
+		vector<ColumnDefinition> columns;
+		auto col = ColumnDefinition(string("__"), LogicalType::UNKNOWN);
+		columns.push_back(std::move(col));
+		info.columns = ColumnList(std::move(columns));
+		auto table_entry = make_uniq<ICTableEntry>(table_info, catalog, schema, info);
+		if (!table_entry->internal) {
+			table_entry->internal = schema.internal;
+		}
+		auto result = table_entry.get();
+		if (result->name.empty()) {
+			throw InternalException("ICTableSet::CreateEntry called with empty name");
+		}
+		table_info.dummy_entry = std::move(table_entry);
+		auto &optional = table_info.dummy_entry.get()->Cast<CatalogEntry>();
+		callback(optional);
 	}
 	// erase not iceberg tables
 	for (auto &entry : non_iceberg_tables) {

test/sql/local/irc/iceberg_catalog_read.test

@@ -19,7 +19,7 @@ statement ok
 CALL enable_logging('HTTP');
 
 statement ok
-set logging_level='debug'
+set logging_level='debug';
 
 statement ok
 CREATE SECRET (

test/sql/local/irc/test_duckdb_catalog_functions_and_iceberg.test

@@ -51,21 +51,18 @@ select count(*) from duckdb_logs_parsed('HTTP');
 query I
 select count(*) from duckdb_logs_parsed('HTTP');
 ----
-5
+3
 
 statement ok
 use memory;
 
-# 3 more requests are made,
-# 2 from previous duckdb_logs_parsed call for 'main', 'default',
-# and 1 for 'memory'
-# requests no longer go up
+# namespace 'memory' is looked up in the iceberg catalog
 query I
 select count(*) from duckdb_logs_parsed('HTTP');
 ----
-8
+4
 
 query I
 select count(*) from duckdb_logs_parsed('HTTP');
 ----
-8
+4

test/sql/local/irc/test_table_information_requests.test

@@ -0,0 +1,110 @@
+# name: test/sql/local/irc/test_table_information_requests.test
+# description: test integration with iceberg catalog read
+# group: [irc]
+
+require-env ICEBERG_SERVER_AVAILABLE
+
+require avro
+
+require parquet
+
+require iceberg
+
+require httpfs
+
+# Do not ignore 'HTTP' error messages!
+set ignore_error_messages
+
+statement ok
+set enable_logging=true
+
+statement ok
+set logging_level='debug'
+
+statement ok
+CALL enable_logging('HTTP');
+
+statement ok
+CREATE SECRET (
+    TYPE S3,
+    KEY_ID 'admin',
+    SECRET 'password',
+    ENDPOINT '127.0.0.1:9000',
+    URL_STYLE 'path',
+    USE_SSL 0
+);
+
+
+statement ok
+ATTACH '' AS my_datalake (
+    TYPE ICEBERG,
+    CLIENT_ID 'admin',
+    CLIENT_SECRET 'password',
+    ENDPOINT 'http://127.0.0.1:8181'
+);
+
+query I
+select count(*) > 10 from (show all tables);
+----
+1
+
+# 1 call for oath, 1 call for config
+# 1 call to list namespaces
+# 1 call to list tables in default
+# 1 call to list tables in level1 namespace (no recursive namespace calls)
+query I
+select count(*) from duckdb_logs_parsed('HTTP');
+----
+5
+
+statement ok
+call truncate_duckdb_logs();
+
+query II
+select column_name, column_type from (describe my_datalake.default.supplier);
+----
+s_suppkey	BIGINT
+s_name	VARCHAR
+s_address	VARCHAR
+s_nationkey	INTEGER
+s_phone	VARCHAR
+s_acctbal	DECIMAL(15,2)
+s_comment	VARCHAR
+
+# one request to verify the default schema
+# another request to verify table default.supplier
+# another request to the table information endpoint
+# FIXME: apparantly there is also a request to an avro file
+query I
+select count(*) from duckdb_logs_parsed('HTTP');
+----
+4
+
+statement ok
+begin;
+
+statement ok
+show all tables;
+
+query I
+select distinct(s_nationkey) from my_datalake.default.supplier order by all limit 5;
+----
+0
+1
+2
+3
+4
+
+statement ok
+commit;
+
+# 5 calls to list the namespaces
+# 1 call the the GetTableInformationEndpoint for supploer
+# (FIXME) 1 call to an avro file in the warehouse
+# 1 call to the manifest file
+# 1 call to the manifest list
+# 2 calls to read parquet files
+query I
+select count(*) from duckdb_logs_parsed('HTTP');
+----
+11

test/sql/local/test_iceberg_and_ducklake.test

@@ -0,0 +1,56 @@
+# name: test/sql/local/test_iceberg_and_ducklake.test
+# description: test integration with iceberg catalog read
+# group: [local]
+
+require-env ICEBERG_SERVER_AVAILABLE
+
+require avro
+
+require parquet
+
+require iceberg
+
+require httpfs
+
+require ducklake
+
+# Do not ignore 'HTTP' error messages!
+set ignore_error_messages
+
+statement ok
+pragma threads=1;
+
+statement ok
+CALL enable_logging('HTTP');
+
+statement ok
+set logging_level='debug';
+
+statement ok
+CREATE SECRET (
+    TYPE S3,
+    KEY_ID 'admin',
+    SECRET 'password',
+    ENDPOINT '127.0.0.1:9000',
+    URL_STYLE 'path',
+    USE_SSL 0
+);
+
+
+statement ok
+ATTACH '' AS my_datalake (
+    TYPE ICEBERG,
+    CLIENT_ID 'admin',
+    CLIENT_SECRET 'password',
+    ENDPOINT 'http://127.0.0.1:8181'
+);
+
+statement ok
+ATTACH 'ducklake:duckdb:__TEST_DIR__/ducklake.duckdb' as my_ducklake (DATA_PATH '__TEST_DIR__/data_path');
+
+# 2 requests to the iceberg catalog for oauth and config
+# 3 requests when attaching ducklake because a ducklake attach calls from duckdb_tables()
+query I
+select count(*) from duckdb_logs_parsed('HTTP');
+----
+5