planner: fix ErrViewInvalid caused by view constant folding

pkg/planner/core/logical_plan_builder.go

@@ -975,11 +975,18 @@ func (b *PlanBuilder) buildSelection(ctx context.Context, p base.LogicalPlan, wh
 	}
 	cnfExpres := make([]expression.Expression, 0)
 	useCache := b.ctx.GetSessionVars().StmtCtx.UseCache()
+	foldEvalCtx := b.ctx.GetExprCtx().GetEvalCtx()
+	if b.ignoreTruncateErrForViewPredicateFolding {
+		// View definitions are built as SELECTs even when they are expanded inside
+		// an outer DML statement, so only that planner-time predicate folding path
+		// should ignore truncate errors like `WHERE ''`.
+		foldEvalCtx = exprctx.CtxWithHandleTruncateErrLevel(b.ctx.GetExprCtx(), errctx.LevelIgnore).GetEvalCtx()
+	}
 	for _, expr := range expressions {
 		cnfItems := expression.SplitCNFItems(expr)
 		for _, item := range cnfItems {
 			if con, ok := item.(*expression.Constant); ok && expression.ConstExprConsiderPlanCache(con, useCache) {
-				ret, _, err := expression.EvalBool(b.ctx.GetExprCtx().GetEvalCtx(), expression.CNFExprs{con}, chunk.Row{})
+				ret, _, err := expression.EvalBool(foldEvalCtx, expression.CNFExprs{con}, chunk.Row{})
 				if err != nil {
 					return nil, errors.Trace(err)
 				}
@@ -5185,6 +5192,13 @@ func (b *PlanBuilder) BuildDataSourceFromView(ctx context.Context, dbName ast.CI
 		b.hintState = originHintState
 		b.ctx.GetSessionVars().PlannerSelectBlockAsName.Store(originPlannerSelectBlockAsName)
 	}()
+	// Only relax truncate handling while folding constant predicates in this
+	// view expansion. Keep the outer statement semantics unchanged.
+	originIgnoreTruncateErrForViewPredicateFolding := b.ignoreTruncateErrForViewPredicateFolding
+	b.ignoreTruncateErrForViewPredicateFolding = true
+	defer func() {
+		b.ignoreTruncateErrForViewPredicateFolding = originIgnoreTruncateErrForViewPredicateFolding
+	}()
 	nodeW := resolve.NewNodeWWithCtx(selectNode, b.resolveCtx)
 	selectLogicalPlan, err := b.Build(ctx, nodeW)
 	if err != nil {

pkg/planner/core/planbuilder.go

@@ -261,6 +261,9 @@ type PlanBuilder struct {
 	partitionedTable []table.PartitionedTable
 	// buildingViewStack is used to check whether there is a recursive view.
 	buildingViewStack set.StringSet
+	// ignoreTruncateErrForViewPredicateFolding narrows truncate relaxation to
+	// constant predicate folding while expanding a view.
+	ignoreTruncateErrForViewPredicateFolding bool
 	// renamingViewName is the name of the view which is being renamed.
 	renamingViewName string
 	// isCreateView indicates whether the query is create view.

tests/integrationtest/r/executor/insert.result

@@ -2443,3 +2443,15 @@ ts
 DROP TABLE t;
 SET @@time_zone = @old_time_zone;
 SET @@sql_mode = @old_sql_mode;
+SET @old_sql_mode_65832 = @@sql_mode;
+SET sql_mode = 'STRICT_TRANS_TABLES';
+CREATE TABLE t_65832_0(c0 BLOB(304));
+CREATE TABLE t_65832_1(c0 CHAR DEFAULT '0');
+CREATE VIEW v_65832(c0) AS SELECT 0.9699394901011086 FROM t_65832_0 INNER JOIN t_65832_0 AS t0_alias ON t_65832_0.c0 WHERE '';
+INSERT INTO t_65832_1 VALUES ('v') ON DUPLICATE KEY UPDATE c0=(SELECT true FROM v_65832 CROSS JOIN t_65832_0 ON (true));
+SELECT * FROM t_65832_1;
+c0
+v
+DROP VIEW v_65832;
+DROP TABLE t_65832_0, t_65832_1;
+SET sql_mode = @old_sql_mode_65832;

tests/integrationtest/t/executor/insert.test

@@ -1783,3 +1783,21 @@ DROP TABLE t;
 SET @@time_zone = @old_time_zone;
 SET @@sql_mode = @old_sql_mode;
 --disable_warnings
+
+# Regression test for issue #65832:
+# INSERT ... ON DUPLICATE KEY UPDATE with a subquery referencing a view whose
+# SELECT definition contains a constant boolean expression (e.g. WHERE '') should
+# not return ErrViewInvalid when the outer statement is an INSERT in strict SQL mode.
+# Root cause: planner-time constant folding inherited the outer INSERT's
+# truncate handling, causing WHERE '' to raise ErrTruncatedWrongVal and then
+# (incorrectly) surface as ErrViewInvalid during view expansion.
+SET @old_sql_mode_65832 = @@sql_mode;
+SET sql_mode = 'STRICT_TRANS_TABLES';
+CREATE TABLE t_65832_0(c0 BLOB(304));
+CREATE TABLE t_65832_1(c0 CHAR DEFAULT '0');
+CREATE VIEW v_65832(c0) AS SELECT 0.9699394901011086 FROM t_65832_0 INNER JOIN t_65832_0 AS t0_alias ON t_65832_0.c0 WHERE '';
+INSERT INTO t_65832_1 VALUES ('v') ON DUPLICATE KEY UPDATE c0=(SELECT true FROM v_65832 CROSS JOIN t_65832_0 ON (true));
+SELECT * FROM t_65832_1;
+DROP VIEW v_65832;
+DROP TABLE t_65832_0, t_65832_1;
+SET sql_mode = @old_sql_mode_65832;