Merge 7a7e90e into 903def9

Author: qrort

ydb/core/kqp/host/kqp_translate.cpp

@@ -95,7 +95,8 @@ NSQLTranslation::TTranslationSettings GetTranslationSettings(NYql::EKikimrQueryT
     settings.DefaultCluster = cluster;
     settings.ClusterMapping = {
         {cluster, TString(NYql::KikimrProviderName)},
-        {"pg_catalog", TString(NYql::PgProviderName)}
+        {"pg_catalog", TString(NYql::PgProviderName)},
+        {"information_schema", TString(NYql::PgProviderName)}
     };
     auto tablePathPrefix = kqpTablePathPrefix;
     if (!tablePathPrefix.empty()) {

ydb/core/kqp/ut/pg/pg_catalog_ut.cpp

@@ -39,6 +39,24 @@ Y_UNIT_TEST_SUITE(PgCatalog) {
             ])", FormatResultSetYson(result.GetResultSet(0)));
         }
     }
+
+    Y_UNIT_TEST(InformationSchema) {
+        TKikimrRunner kikimr(NKqp::TKikimrSettings().SetWithSampleTables(false));
+        auto db = kikimr.GetQueryClient();
+        auto settings = NYdb::NQuery::TExecuteQuerySettings().Syntax(NYdb::NQuery::ESyntax::Pg);
+        {
+            auto result = db.ExecuteQuery(R"(
+                select column_name from information_schema.columns
+                order by table_schema, table_name, column_name limit 5
+            )", NYdb::NQuery::TTxControl::BeginTx().CommitTx(), settings).ExtractValueSync();
+            UNIT_ASSERT_C(result.IsSuccess(), result.GetIssues().ToString());
+            UNIT_ASSERT_C(!result.GetResultSets().empty(), "no result sets");
+            CompareYson(R"([
+                ["authorization_identifier"];["fdwoptions"];["fdwowner"];["foreign_data_wrapper_catalog"];
+                ["foreign_data_wrapper_language"]
+            ])", FormatResultSetYson(result.GetResultSet(0)));
+        }
+    }
 }
 
 } // namespace NKqp

ydb/library/yql/sql/pg/pg_sql.cpp

@@ -2559,7 +2559,8 @@ class TConverter : public IPGParseEvents {
     TAstNode* BuildTableKeyExpression(const TStringBuf relname,
         const TStringBuf cluster, bool isScheme = false
     ) {
-        TString tableName = (cluster == "pg_catalog") ? TString(relname) : TablePathPrefix + relname;
+        bool noPrefix = (cluster == "pg_catalog" || cluster == "information_schema");
+        TString tableName = noPrefix ? TString(relname) : TablePathPrefix + relname;
         return L(A("Key"), QL(QA(isScheme ? "tablescheme" : "table"),
                             L(A("String"), QAX(std::move(tableName)))));
     }