[YQL-10265] Improve frame validation

ref:96e25def267e496f2222b87d57dac3389806e686

2 files changed, 17 insertions, 3 deletions

diff --git a/ydb/library/yql/core/yql_opt_window.cpp b/ydb/library/yql/core/yql_opt_window.cpp
index aebe6e901a..e85982c21f 100644
--- a/ydb/library/yql/core/yql_opt_window.cpp
+++ b/ydb/library/yql/core/yql_opt_window.cpp
@@ -2568,6 +2568,10 @@ TMaybe<TWindowFrameSettings> TWindowFrameSettings::TryParse(const TExprNode& nod
                 auto type = fb->Head().Content();
                 if (type == "currentRow") {
                     if (fb->ChildrenSize() == 1) {
+                        if (!node.IsCallable("WinOnRange")) {
+                            ctx.AddError(TIssue(ctx.GetPosition(fb->Pos()), TStringBuilder() << "currentRow should only be used for RANGE"));
+                            return {};
+                        }
                         frameBound = fb;
                         continue;
                     }
@@ -2699,6 +2703,16 @@ TMaybe<i32> TWindowFrameSettings::GetLastOffset() const {
     return LastOffset;
 }
 
+TCoFrameBound TWindowFrameSettings::GetFirst() const {
+    YQL_ENSURE(First);
+    return TCoFrameBound(First);
+}
+
+TCoFrameBound TWindowFrameSettings::GetLast() const {
+    YQL_ENSURE(Last);
+    return TCoFrameBound(Last);
+}
+
 TExprNode::TPtr ZipWithSessionParamsLambda(TPositionHandle pos, const TExprNode::TPtr& partitionKeySelector,
     const TExprNode::TPtr& sessionKeySelector, const TExprNode::TPtr& sessionInit,
     const TExprNode::TPtr& sessionUpdate, TExprContext& ctx)
diff --git a/ydb/library/yql/core/yql_opt_window.h b/ydb/library/yql/core/yql_opt_window.h
index c0c7d8fa69..6e51a6c794 100644
--- a/ydb/library/yql/core/yql_opt_window.h
+++ b/ydb/library/yql/core/yql_opt_window.h
@@ -29,8 +29,8 @@ public:
     TMaybe<i32> GetFirstOffset() const;
     TMaybe<i32> GetLastOffset() const;
 
-    TCoFrameBound GetFirst(bool& isPreceding) const;
-    TCoFrameBound GetLast(bool& isPreceding) const;
+    TCoFrameBound GetFirst() const;
+    TCoFrameBound GetLast() const;
 
     bool IsNonEmpty() const { return NeverEmpty; }
     bool IsCompact() const { return Compact; }
@@ -41,7 +41,7 @@ private:
     TMaybe<i32> FirstOffset;
     TExprNode::TPtr Last;
     TMaybe<i32> LastOffset;
-    bool NeverEmpty = true;
+    bool NeverEmpty = false;
     bool Compact = false;
 };