YQL-20345: Disable EXCEPT/INTERSECT/DISTINCT before 2025.03

Added absent checks for `langVer` at `EXCEPT/INTERSECT/DISTINCT`
translation. In next PR will get rid of `.sqlx` file extensions.
commit_hash:699cc8f6084d1d2fc19ecd53c35a56496dc842f4

4 files changed, 39 insertions, 3 deletions

diff --git a/yql/essentials/sql/v1/context.cpp b/yql/essentials/sql/v1/context.cpp
index 8d412ba2477..cdf2a60824d 100644
--- a/yql/essentials/sql/v1/context.cpp
+++ b/yql/essentials/sql/v1/context.cpp
@@ -679,6 +679,10 @@ void TTranslation::AltNotImplemented(const TString& ruleName, ui32 altCase, cons
     Error() << ruleName << ": alternative is not implemented yet: " << AltDescription(node, altCase, descr);
 }
 
+bool TTranslation::IsBackwardCompatibleFeatureAvailable(NYql::TLangVersion langVer) const {
+    return NYql::IsBackwardCompatibleFeatureAvailable(Ctx_.Settings.LangVer, langVer, Ctx_.Settings.BackportMode);
+}
+
 void EnumerateSqlFlags(std::function<void(std::string_view)> callback) {
     for (const auto& x : CTX_PRAGMA_FIELDS) {
         callback(x.first);
diff --git a/yql/essentials/sql/v1/context.h b/yql/essentials/sql/v1/context.h
index aa30982c35c..7ae995059a8 100644
--- a/yql/essentials/sql/v1/context.h
+++ b/yql/essentials/sql/v1/context.h
@@ -477,6 +477,8 @@ namespace NSQLTranslationV1 {
         void AltNotImplemented(const TString& ruleName, ui32 altCase, const google::protobuf::Message& node, const google::protobuf::Descriptor* descr);
         TString AltDescription(const google::protobuf::Message& node, ui32 altCase, const google::protobuf::Descriptor* descr) const;
 
+        bool IsBackwardCompatibleFeatureAvailable(NYql::TLangVersion langVer) const;
+
     protected:
         TContext& Ctx_;
     };
diff --git a/yql/essentials/sql/v1/sql_select.cpp b/yql/essentials/sql/v1/sql_select.cpp
index a846dff5483..3dd5043438d 100644
--- a/yql/essentials/sql/v1/sql_select.cpp
+++ b/yql/essentials/sql/v1/sql_select.cpp
@@ -1460,7 +1460,24 @@ TSourcePtr TSqlSelect::BuildUnionException(const TRule& node, TPosition& pos, TS
     for (int i = 0; i < tail.size(); ++i) {
         const auto& nextBlock = tail[i];
 
-        TString nextOp = ToLowerUTF8(Token(nextBlock.GetRule_union_op1().GetToken1()));
+        const NSQLv1Generated::TToken& token = nextBlock.GetRule_union_op1().GetToken1();
+        TString nextOp = ToLowerUTF8(Token(token));
+        if (nextOp != "union" && !IsBackwardCompatibleFeatureAvailable(MakeLangVersion(2025, 3))) {
+            Ctx_.Error(Ctx_.TokenPosition(token))
+                << "EXCEPT/INTERSECT is not available before version 2025.03";
+            return nullptr;
+        }
+
+        if (nextBlock.GetRule_union_op1().HasBlock2()) {
+            const NSQLv1Generated::TToken& token = nextBlock.GetRule_union_op1().GetBlock2().GetToken1();
+            const TString qualifier = ToLowerUTF8(Token(token));
+            if (qualifier == "distinct" && !IsBackwardCompatibleFeatureAvailable(MakeLangVersion(2025, 3))) {
+                Ctx_.Error(Ctx_.TokenPosition(token))
+                    << "UNION DISTINCT is not available before version 2025.03";
+                return nullptr;
+            }
+        }
+
         bool isNextAllQualified = IsAllQualifiedOp(nextBlock.GetRule_union_op1());
 
         TSelectKindPlacement nextPlacement = {
@@ -1536,7 +1553,14 @@ TSourcePtr TSqlSelect::BuildIntersection(
     for (int i = 0; i < tail.size(); ++i) {
         const auto& nextBlock = tail[i];
 
-        TString nextOp = ToLowerUTF8(Token(nextBlock.GetRule_intersect_op1().GetToken1()));
+        const NSQLv1Generated::TToken& token = nextBlock.GetRule_intersect_op1().GetToken1();
+        if (!IsBackwardCompatibleFeatureAvailable(MakeLangVersion(2025, 3))) {
+            Ctx_.Error(Ctx_.TokenPosition(token))
+                << "EXCEPT/INTERSECT is not available before version 2025.03";
+            return nullptr;
+        }
+
+        TString nextOp = ToLowerUTF8(Token(token));
         bool isNextAllQualified = IsAllQualifiedOp(nextBlock.GetRule_intersect_op1());
 
         TSelectKindPlacement nextPlacement = {
diff --git a/yql/essentials/sql/v1/sql_ut_common.h b/yql/essentials/sql/v1/sql_ut_common.h
index 5b0c5a28f26..a47b22aa0bc 100644
--- a/yql/essentials/sql/v1/sql_ut_common.h
+++ b/yql/essentials/sql/v1/sql_ut_common.h
@@ -1754,7 +1754,13 @@ Y_UNIT_TEST_SUITE(SqlParsingOnly) {
     }
 
     Y_UNIT_TEST(UnionDistinctTest) {
-        NYql::TAstParseResult res = SqlToYql("SELECT key FROM plato.Input UNION DISTINCT select subkey FROM plato.Input;");
+        NSQLTranslation::TTranslationSettings settings;
+        settings.LangVer = NYql::MakeLangVersion(2025, 3);
+
+        NYql::TAstParseResult res = SqlToYqlWithSettings(
+            R"sql(SELECT key FROM plato.Input UNION DISTINCT SELECT subkey FROM plato.Input;)sql",
+            settings);
+
         UNIT_ASSERT(res.Root);
 
         TWordCountHive elementStat = {{TString("Union"), 0}};