Emit proper error message when top level named subquery statement is found in libraries

4 files changed, 58 insertions, 1 deletions

diff --git a/ydb/library/yql/sql/v1/node.h b/ydb/library/yql/sql/v1/node.h
index f2c60b8dcf..538202854f 100644
--- a/ydb/library/yql/sql/v1/node.h
+++ b/ydb/library/yql/sql/v1/node.h
@@ -1307,6 +1307,7 @@ namespace NSQLTranslationV1 {
     // Implemented in select.cpp
     TNodePtr BuildSubquery(TSourcePtr source, const TString& alias, bool inSubquery, int ensureTupleSize, TScopedStatePtr scoped);
     TNodePtr BuildSubqueryRef(TNodePtr subquery, const TString& alias, int tupleIndex = -1);
+    TNodePtr BuildInvalidSubqueryRef(TPosition subqueryPos);
     TNodePtr BuildSourceNode(TPosition pos, TSourcePtr source, bool checkExist = false);
     TSourcePtr BuildMuxSource(TPosition pos, TVector<TSourcePtr>&& sources);
     TSourcePtr BuildFakeSource(TPosition pos, bool missingFrom = false, bool inSubquery = false);
diff --git a/ydb/library/yql/sql/v1/select.cpp b/ydb/library/yql/sql/v1/select.cpp
index a7d2d0a8c4..c3fa583668 100644
--- a/ydb/library/yql/sql/v1/select.cpp
+++ b/ydb/library/yql/sql/v1/select.cpp
@@ -650,6 +650,37 @@ TNodePtr BuildSubqueryRef(TNodePtr subquery, const TString& alias, int tupleInde
     return new TSubqueryRefNode(std::move(subquery), alias, tupleIndex);
 }
 
+class TInvalidSubqueryRefNode: public ISource {
+public:
+    TInvalidSubqueryRefNode(TPosition pos)
+        : ISource(pos)
+        , Pos(pos)
+    {
+    }
+
+    bool DoInit(TContext& ctx, ISource* src) override {
+        Y_UNUSED(src);
+        ctx.Error(Pos) << "Named subquery can not be used as a top level statement in libraries";
+        return false;
+    }
+
+    TNodePtr Build(TContext& ctx) override {
+        Y_UNUSED(ctx);
+        return {};
+    }
+
+    TPtr DoClone() const final {
+        return new TInvalidSubqueryRefNode(Pos);
+    }
+
+protected:
+    const TPosition Pos;
+};
+
+TNodePtr BuildInvalidSubqueryRef(TPosition subqueryPos) {
+    return new TInvalidSubqueryRefNode(subqueryPos);
+}
+
 class TTableSource: public IRealSource {
 public:
     TTableSource(TPosition pos, const TTableRef& table, const TString& label)
diff --git a/ydb/library/yql/sql/v1/sql.cpp b/ydb/library/yql/sql/v1/sql.cpp
index b3bd162c18..475ccc5d18 100644
--- a/ydb/library/yql/sql/v1/sql.cpp
+++ b/ydb/library/yql/sql/v1/sql.cpp
@@ -8634,7 +8634,11 @@ bool TSqlQuery::Statement(TVector<TNodePtr>& blocks, const TRule_sql_stmt_core&
             }
             TVector<TNodePtr> nodes;
             auto subquery = nodeExpr->GetSource();
-            if (subquery) {
+            if (subquery && Mode == NSQLTranslation::ESqlMode::LIBRARY && Ctx.ScopeLevel == 0) {
+                for (size_t i = 0; i < names.size(); ++i) {
+                    nodes.push_back(BuildInvalidSubqueryRef(subquery->GetPos()));
+                }
+            } else if (subquery) {
                 const auto alias = Ctx.MakeName("subquerynode");
                 const auto ref = Ctx.MakeName("subquery");
                 blocks.push_back(BuildSubquery(subquery, alias,
diff --git a/ydb/library/yql/sql/v1/sql_ut.cpp b/ydb/library/yql/sql/v1/sql_ut.cpp
index 9fe02d1f2a..6e993d79a4 100644
--- a/ydb/library/yql/sql/v1/sql_ut.cpp
+++ b/ydb/library/yql/sql/v1/sql_ut.cpp
@@ -3551,6 +3551,27 @@ select FormatType($f());
             "<main>:1:42: Error: Source does not allow column references\n"
             "<main>:1:71: Error: Column reference 'subkey'\n");
     }
+
+    Y_UNIT_TEST(ErrorInLibraryWithTopLevelNamedSubquery) {
+        TString withUnusedSubq = "$unused = select max(key) from plato.Input;\n"
+                                 "\n"
+                                 "define subquery $foo() as\n"
+                                 "  $count = select count(*) from plato.Input;\n"
+                                 "  select * from plato.Input limit $count / 2;\n"
+                                 "end define;\n"
+                                 "export $foo;\n";
+        UNIT_ASSERT(SqlToYqlWithMode(withUnusedSubq, NSQLTranslation::ESqlMode::LIBRARY).IsOk());
+
+        TString withTopLevelSubq = "$count = select count(*) from plato.Input;\n"
+                                   "\n"
+                                   "define subquery $foo() as\n"
+                                   "  select * from plato.Input limit $count / 2;\n"
+                                   "end define;\n"
+                                   "export $foo;\n";
+        auto res = SqlToYqlWithMode(withTopLevelSubq, NSQLTranslation::ESqlMode::LIBRARY);
+        UNIT_ASSERT(!res.Root);
+        UNIT_ASSERT_NO_DIFF(Err2Str(res), "<main>:1:17: Error: Named subquery can not be used as a top level statement in libraries\n");
+    }
 }
 
 void CheckUnused(const TString& req, const TString& symbol, unsigned row, unsigned col) {