From 5553401041960223e9f7a48398657ff26077aa65 Mon Sep 17 00:00:00 2001
From: Andrey Neporada <aneporada@ydb.tech>
Date: Fri, 16 Feb 2024 15:26:09 +0300
Subject: [PATCH] [YQL-17818] Fix error handling in SessionWindow (#1988)

---
 ydb/library/yql/sql/v1/builtin.cpp |  5 +++++
 ydb/library/yql/sql/v1/sql_ut.cpp  | 16 ++++++++++++++++
 2 files changed, 21 insertions(+)

diff --git a/ydb/library/yql/sql/v1/builtin.cpp b/ydb/library/yql/sql/v1/builtin.cpp
index fecbdebcbbe1..a24dcb1dc94a 100644
--- a/ydb/library/yql/sql/v1/builtin.cpp
+++ b/ydb/library/yql/sql/v1/builtin.cpp
@@ -2097,6 +2097,11 @@ class TSessionStart final : public INode {
             }
         }
 
+        if (sessionWindow->HasState(ENodeState::Failed)) {
+            return false;
+        }
+
+        YQL_ENSURE(sessionWindow->HasState(ENodeState::Initialized));
         YQL_ENSURE(sessionWindow->GetLabel());
         Node = Y("Member", "row", BuildQuotedAtom(Pos, sessionWindow->GetLabel()));
         if (OverWindow) {
diff --git a/ydb/library/yql/sql/v1/sql_ut.cpp b/ydb/library/yql/sql/v1/sql_ut.cpp
index d640235bf2ed..78a05a85c1d5 100644
--- a/ydb/library/yql/sql/v1/sql_ut.cpp
+++ b/ydb/library/yql/sql/v1/sql_ut.cpp
@@ -4375,6 +4375,22 @@ select FormatType($f());
         UNIT_ASSERT_NO_DIFF(Err2Str(res),
             "<main>:1:15: Error: Selecting data from monitoring source is not supported\n");
     }
+
+    Y_UNIT_TEST(SessionStartAndSessionStateShouldSurviveSessionWindowArgsError){
+        TString query = R"(
+            $init = ($_row) -> (min(1, 2)); -- error: aggregation func min() can not be used here
+            $calculate = ($_row, $_state) -> (1);
+            $update = ($_row, $_state) -> (2);
+            SELECT
+                SessionStart() over w as session_start,
+                SessionState() over w as session_state,
+            FROM plato.Input as t
+            WINDOW w AS (
+                PARTITION BY user, SessionWindow(ts + 1, $init, $update, $calculate)
+            )
+        )";
+        ExpectFailWithError(query, "<main>:2:33: Error: Aggregation function Min requires exactly 1 argument(s), given: 2\n");
+    }
 }
 
 void CheckUnused(const TString& req, const TString& symbol, unsigned row, unsigned col) {