From 20aef2e63f764c7e13e75bad33eed4cba371ced1 Mon Sep 17 00:00:00 2001
From: Vitalii Gridnev <gridnevvvit@gmail.com>
Date: Wed, 24 Apr 2024 19:59:44 +0300
Subject: [PATCH] implicit cast for default values

---
 ydb/core/kqp/provider/yql_kikimr_type_ann.cpp | 31 ++++++++++++++++---
 ydb/core/kqp/ut/pg/kqp_pg_ut.cpp              |  1 +
 2 files changed, 27 insertions(+), 5 deletions(-)

diff --git a/ydb/core/kqp/provider/yql_kikimr_type_ann.cpp b/ydb/core/kqp/provider/yql_kikimr_type_ann.cpp
index 06388123bcb7..ffb188b5f742 100644
--- a/ydb/core/kqp/provider/yql_kikimr_type_ann.cpp
+++ b/ydb/core/kqp/provider/yql_kikimr_type_ann.cpp
@@ -294,7 +294,7 @@ namespace {
         return true;
     }
 
-    bool ParseConstraintNode(TExprContext& ctx, TKikimrColumnMetadata& columnMeta, const TExprList& columnTuple, TCoNameValueTuple constraint,  TKikimrConfiguration& config, bool isAlter = false) {
+    bool ParseConstraintNode(TExprContext& ctx, TKikimrColumnMetadata& columnMeta, const TExprList& columnTuple, TCoNameValueTuple constraint,  TKikimrConfiguration& config, bool& needEval, bool isAlter = false) {
         auto nameNode = columnTuple.Item(0).Cast<TCoAtom>();
         auto typeNode = columnTuple.Item(1);
 
@@ -341,9 +341,23 @@ namespace {
             }
 
             if (!skipAnnotationValidation && !IsSameAnnotation(*defaultType, *actualType)) {
-                ctx.AddError(TIssue(ctx.GetPosition(constraint.Pos()), TStringBuilder() << "Default expr " << columnName
-                    << " type mismatch, expected: " << (*actualType) << ", actual: " << *(defaultType)));
+                auto constrPtr = constraint.Value().Cast().Ptr();
+                auto status = TryConvertTo(constrPtr, *type, ctx);
+                if (status == IGraphTransformer::TStatus::Error) {
+                    ctx.AddError(TIssue(ctx.GetPosition(constraint.Pos()), TStringBuilder() << "Default expr " << columnName
+                        << " type mismatch, expected: " << (*actualType) << ", actual: " << *(defaultType)));
                     return false;
+                } else if (status == IGraphTransformer::TStatus::Repeat) {
+                    auto evaluatedExpr = ctx.Builder(constrPtr->Pos())
+                        .Callable("EvaluateExpr")
+                        .Add(0, constrPtr)
+                        .Seal()
+                        .Build();
+
+                    constraint.Ptr()->ChildRef(TCoNameValueTuple::idx_Value) = evaluatedExpr;
+                    needEval = true;
+                    return true;
+                }
             }
 
             if (columnMeta.IsDefaultKindDefined()) {
@@ -863,9 +877,15 @@ virtual TStatus HandleCreateTable(TKiCreateTable create, TExprContext& ctx) over
             if (columnTuple.Size() > 2) {
                 const auto& columnConstraints = columnTuple.Item(2).Cast<TCoNameValueTuple>();
                 for(const auto& constraint: columnConstraints.Value().Cast<TCoNameValueTupleList>()) {
-                    if (!ParseConstraintNode(ctx, columnMeta, columnTuple, constraint, SessionCtx->Config())) {
+                    bool needEval = false;
+                    if (!ParseConstraintNode(ctx, columnMeta, columnTuple, constraint, SessionCtx->Config(), needEval)) {
                         return TStatus::Error;
                     }
+
+                    if (needEval) {
+                        ctx.Step.Repeat(TExprStep::ExprEval);
+                        return TStatus(TStatus::Repeat, true);
+                    }
                 }
             }
 
@@ -1278,7 +1298,8 @@ virtual TStatus HandleCreateTable(TKiCreateTable create, TExprContext& ctx) over
                     if (columnTuple.Size() > 2) {
                         const auto& columnConstraints = columnTuple.Item(2).Cast<TCoNameValueTuple>();
                         for(const auto& constraint: columnConstraints.Value().Cast<TCoNameValueTupleList>()) {
-                            if (!ParseConstraintNode(ctx, columnMeta, columnTuple, constraint, SessionCtx->Config(), true)) {
+                            bool needEval = false;
+                            if (!ParseConstraintNode(ctx, columnMeta, columnTuple, constraint, SessionCtx->Config(), needEval, true)) {
                                 return TStatus::Error;
                             }
                         }
diff --git a/ydb/core/kqp/ut/pg/kqp_pg_ut.cpp b/ydb/core/kqp/ut/pg/kqp_pg_ut.cpp
index f3c2c3678cfb..e935e675cb70 100644
--- a/ydb/core/kqp/ut/pg/kqp_pg_ut.cpp
+++ b/ydb/core/kqp/ut/pg/kqp_pg_ut.cpp
@@ -3743,6 +3743,7 @@ Y_UNIT_TEST_SUITE(KqpPg) {
                     d varchar(20) DEFAULT 'foo'::varchar(2),
                     e int DEFAULT NULL,
                     f bit varying(5) DEFAULT '1001',
+                    g bigint DEFAULT 0 NOT NULL,
                     PRIMARY KEY(a)
                 );
             )", NYdb::NQuery::TTxControl::NoTx(), settings).ExtractValueSync();