[YQL-10265] Support implicit row peers when frame definition is missing (sql part)

ref:17a7f716fc0cc4c71162338230544795c45bd59b

4 files changed, 41 insertions, 10 deletions

diff --git a/ydb/library/yql/sql/v1/context.cpp b/ydb/library/yql/sql/v1/context.cpp
index c08fe96caeb..7beccd30f42 100644
--- a/ydb/library/yql/sql/v1/context.cpp
+++ b/ydb/library/yql/sql/v1/context.cpp
@@ -53,6 +53,7 @@ THashMap<TStringBuf, TPragmaField> CTX_PRAGMA_FIELDS = {
     {"CoalesceJoinKeysOnQualifiedAll", &TContext::CoalesceJoinKeysOnQualifiedAll},
     {"UnorderedSubqueries", &TContext::UnorderedSubqueries},
     {"FlexibleTypes", &TContext::FlexibleTypes},
+    {"AnsiCurrentRow", &TContext::AnsiCurrentRow},
 };
 
 typedef TMaybe<bool> TContext::*TPragmaMaybeField;
diff --git a/ydb/library/yql/sql/v1/context.h b/ydb/library/yql/sql/v1/context.h
index 89517574862..e65d673ea13 100644
--- a/ydb/library/yql/sql/v1/context.h
+++ b/ydb/library/yql/sql/v1/context.h
@@ -254,6 +254,8 @@ namespace NSQLTranslationV1 {
         ui32 PragmaGroupByCubeLimit = 5;
         // if FlexibleTypes=true, emit TypeOrMember callable and resolve Type/Column uncertainty on type annotation stage, otherwise always emit Type
         bool FlexibleTypes = false;
+        // see YQL-10265
+        bool AnsiCurrentRow = false;
         THashMap<TString, TMaybe<TString>> Libraries; // alias -> optional file
         THashMap<TString, ui32> PackageVersions;
         NYql::TWarningPolicy WarningPolicy;
diff --git a/ydb/library/yql/sql/v1/node.cpp b/ydb/library/yql/sql/v1/node.cpp
index 870bbd9cc7f..bd9a303e092 100644
--- a/ydb/library/yql/sql/v1/node.cpp
+++ b/ydb/library/yql/sql/v1/node.cpp
@@ -1839,17 +1839,17 @@ TNodePtr BuildFrameNode(const TFrameBound& frame) {
     TNodePtr node = frame.Bound;
     TPosition pos = frame.Pos;
     if (frame.Settings == FrameCurrentRow) {
-        node = new TCallNodeImpl(pos, "Int32", { BuildQuotedAtom(pos, "0", TNodeFlags::Default) });
+        node = BuildQuotedAtom(pos, "currentRow", TNodeFlags::Default);
     } else if (!node) {
         node = BuildLiteralVoid(pos);
     } else if (node->IsLiteral()) {
         YQL_ENSURE(node->GetLiteralType() == "Int32");
-        auto value = node->GetLiteralValue();
-        YQL_ENSURE(!value.StartsWith('-'));
+        i32 value = FromString<i32>(node->GetLiteralValue());
+        YQL_ENSURE(value >= 0);
         if (frame.Settings == FramePreceding) {
-            value = "-" + value;
+            value = -value;
         }
-        node = new TCallNodeImpl(pos, "Int32", { BuildQuotedAtom(pos, value, TNodeFlags::Default) });
+        node = new TCallNodeImpl(pos, "Int32", { BuildQuotedAtom(pos, ToString(value), TNodeFlags::Default) });
     } else {
         if (frame.Settings == FramePreceding) {
             node = new TCallNodeImpl(pos, "Minus", { node->Clone() });
diff --git a/ydb/library/yql/sql/v1/sql.cpp b/ydb/library/yql/sql/v1/sql.cpp
index cba19761b9c..2b0c8178708 100644
--- a/ydb/library/yql/sql/v1/sql.cpp
+++ b/ydb/library/yql/sql/v1/sql.cpp
@@ -6909,6 +6909,22 @@ bool TSqlTranslation::FrameClause(const TRule_window_frame_clause& rule, TFrameS
         return false;
     }
 
+    if (frameSpec->FrameType != EFrameType::FrameByRange) {
+        // replace FrameCurrentRow for ROWS/GROUPS with 0 preceding/following
+        // FrameCurrentRow has special meaning ( = first/last peer row)
+        auto replaceCurrent = [](TFrameBound& frame, bool preceding) {
+            frame.Settings = preceding ? EFrameSettings::FramePreceding : EFrameSettings::FrameFollowing;
+            frame.Bound = new TLiteralNumberNode<i32>(frame.Pos, "Int32", "0");
+        };
+        if (frameSpec->FrameBegin->Settings == EFrameSettings::FrameCurrentRow) {
+            replaceCurrent(*frameSpec->FrameBegin, true);
+        }
+
+        if (frameSpec->FrameEnd->Settings == EFrameSettings::FrameCurrentRow) {
+            replaceCurrent(*frameSpec->FrameEnd, false);
+        }
+    }
+
     return true;
 }
 
@@ -6961,21 +6977,27 @@ TWindowSpecificationPtr TSqlTranslation::WindowSpecification(const TRule_window_
         winSpecPtr->Frame->FrameType = EFrameType::FrameByRows;
         winSpecPtr->Frame->FrameExclusion = EFrameExclusions::FrameExclNone;
 
+        // BETWEEN UNBOUNDED PRECEDING AND ...
         winSpecPtr->Frame->FrameBegin = new TFrameBound;
         winSpecPtr->Frame->FrameBegin->Settings = EFrameSettings::FramePreceding;
 
         const bool ordered = !winSpecPtr->OrderBy.empty();
         winSpecPtr->Frame->FrameEnd = new TFrameBound;
+        winSpecPtr->Frame->FrameBegin->Pos = winSpecPtr->Frame->FrameEnd->Pos = Ctx.Pos();
         if (ordered) {
-            // ROWS BETWEEN UNBOUNDED PRECEDING AND CURRENT ROW
-            winSpecPtr->Frame->FrameEnd->Settings = EFrameSettings::FrameCurrentRow;
+            if (Ctx.AnsiCurrentRow) {
+                // RANGE BETWEEN UNBOUNDED PRECEDING AND CURRENT ROW
+                // We emit FrameByRows here, but FrameCurrentRow works specially for ROWS
+                winSpecPtr->Frame->FrameEnd->Settings = EFrameSettings::FrameCurrentRow;
+            } else {
+                // ROWS BETWEEN UNBOUNDED PRECEDING AND 0 FOLLOWING
+                winSpecPtr->Frame->FrameEnd->Settings = EFrameSettings::FrameFollowing;
+                winSpecPtr->Frame->FrameEnd->Bound = new TLiteralNumberNode<i32>(Ctx.Pos(), "Int32", "0");
+            }
         } else {
             // ROWS BETWEEN UNBOUNDED PRECEDING AND UNBOUNDED FOLLOWING
             winSpecPtr->Frame->FrameEnd->Settings = EFrameSettings::FrameFollowing;
         }
-
-        // TODO: According to standard this should be RANGE BETWEEN UNBOUNDED PRECEDING AND CURRENT ROW with order by clause
-        // TODO: and RANGE BETWEEN UNBOUNDED PRECEDING AND UNBOUNDED FOLLOWING without order by
     }
     return winSpecPtr;
 }
@@ -9575,6 +9597,12 @@ TNodePtr TSqlQuery::PragmaStatement(const TRule_pragma_stmt& stmt, bool& success
         } else if (normalizedPragma == "disableflexibletypes") {
             Ctx.FlexibleTypes = false;
             Ctx.IncrementMonCounter("sql_pragma", "DisableFlexibleTypes");
+        } else if (normalizedPragma == "ansicurrentrow") {
+            Ctx.AnsiCurrentRow = true;
+            Ctx.IncrementMonCounter("sql_pragma", "AnsiCurrentRow");
+        } else if (normalizedPragma == "disableansicurrentrow") {
+            Ctx.AnsiCurrentRow = false;
+            Ctx.IncrementMonCounter("sql_pragma", "DisableAnsiCurrentRow");
         } else {
             Error() << "Unknown pragma: " << pragma;
             Ctx.IncrementMonCounter("sql_errors", "UnknownPragma");