Fixed using TOP 1 within IN clause

Fixes #429
MarkMpn · Feb 8, 2024 · a19da3c · a19da3c
1 parent ff4310c
commit a19da3c
Show file tree

Hide file tree

Showing 2 changed files with 44 additions and 6 deletions.
diff --git a/MarkMpn.Sql4Cds.Engine.Tests/ExecutionPlanTests.cs b/MarkMpn.Sql4Cds.Engine.Tests/ExecutionPlanTests.cs
@@ -6845,5 +6845,43 @@ BEGIN CATCH
                 Assert.AreEqual(1026, ex.Errors.Single().Number);
             }
         }
+
+        [DataTestMethod]
+        [DataRow(1)]
+        [DataRow(2)]
+        [DataRow(3)]
+        public void UpdateTop(int top)
+        {
+            var planBuilder = new ExecutionPlanBuilder(_localDataSource.Values, this);
+
+            var query = $@"
+UPDATE account
+SET    name = 'Test'
+WHERE  accountid IN (SELECT   TOP {top} accountid
+                     FROM     account
+                     WHERE    name = 'Data8'
+                              AND employees > 0
+                     ORDER BY accountid)";
+
+            var plans = planBuilder.Build(query, null, out _);
+
+            Assert.AreEqual(1, plans.Length);
+
+            var update = AssertNode<UpdateNode>(plans[0]);
+            var compute = AssertNode<ComputeScalarNode>(update.Source);
+            Assert.AreEqual("'Test'", compute.Columns["Expr3"].ToSql());
+            var fetch = AssertNode<FetchXmlScan>(compute.Source);
+            AssertFetchXml(fetch, $@"
+                <fetch top='{top}'>
+                  <entity name='account'>
+                    <attribute name='accountid' />
+                    <filter>
+                      <condition attribute='name' operator='eq' value='Data8' />
+                      <condition attribute='employees' operator='gt' value='0' />
+                    </filter>
+                    <order attribute='accountid' />
+                  </entity>
+                </fetch>");
+        }
     }
 }
diff --git a/MarkMpn.Sql4Cds.Engine/ExecutionPlanBuilder.cs b/MarkMpn.Sql4Cds.Engine/ExecutionPlanBuilder.cs
@@ -2628,7 +2628,7 @@ private IDataExecutionPlanNodeInternal ConvertInSubqueries(IDataExecutionPlanNod
 
                 if (references.Count == 0)
                 {
-                    if (UseMergeJoin(source, innerQuery.Source, context, references, testColumn, lhsCol.GetColumnName(), true, out var outputCol, out var merge))
+                    if (UseMergeJoin(source, innerQuery.Source, context, references, testColumn, lhsCol.GetColumnName(), true, true, out var outputCol, out var merge))
                     {
                         testColumn = outputCol;
                         join = merge;
@@ -2790,7 +2790,7 @@ private IDataExecutionPlanNodeInternal ConvertExistsSubqueries(IDataExecutionPla
                         }
                     };
                 }
-                else if (UseMergeJoin(source, innerQuery.Source, context, references, null, null, true, out testColumn, out var merge))
+                else if (UseMergeJoin(source, innerQuery.Source, context, references, null, null, true, false, out testColumn, out var merge))
                 {
                     join = merge;
                 }
@@ -3626,7 +3626,7 @@ private ColumnReferenceExpression ConvertScalarSubqueries(TSqlFragment expressio
                 string outputcol;
                 var subqueryCol = subqueryPlan.ColumnSet[0].SourceColumn;
                 BaseJoinNode join = null;
-                if (UseMergeJoin(node, subqueryPlan.Source, context, outerReferences, subqueryCol, null, false, out outputcol, out var merge))
+                if (UseMergeJoin(node, subqueryPlan.Source, context, outerReferences, subqueryCol, null, false, true, out outputcol, out var merge))
                 {
                     join = merge;
                 }
@@ -3722,7 +3722,7 @@ private ColumnReferenceExpression ConvertScalarSubqueries(TSqlFragment expressio
             return null;
         }
 
-        private bool UseMergeJoin(IDataExecutionPlanNodeInternal node, IDataExecutionPlanNodeInternal subqueryPlan, NodeCompilationContext context, Dictionary<string, string> outerReferences, string subqueryCol, string inPredicateCol, bool semiJoin, out string outputCol, out MergeJoinNode merge)
+        private bool UseMergeJoin(IDataExecutionPlanNodeInternal node, IDataExecutionPlanNodeInternal subqueryPlan, NodeCompilationContext context, Dictionary<string, string> outerReferences, string subqueryCol, string inPredicateCol, bool semiJoin, bool preserveTop, out string outputCol, out MergeJoinNode merge)
         {
             outputCol = null;
             merge = null;
@@ -3735,7 +3735,7 @@ private bool UseMergeJoin(IDataExecutionPlanNodeInternal node, IDataExecutionPla
             if (alias != null)
                 subNode = alias.Source;
 
-            if (subNode is TopNode top && top.Top is IntegerLiteral topLiteral && topLiteral.Value == "1")
+            if (subNode is TopNode top && !preserveTop)
                 subNode = top.Source;
 
             var filter = subNode as FilterNode;
@@ -4352,7 +4352,7 @@ private IDataExecutionPlanNodeInternal ConvertTableReference(TableReference refe
                         var spool = new TableSpoolNode { Source = rhs, SpoolType = SpoolType.Lazy };
                         rhs = spool;
                     }
-                    else if (UseMergeJoin(lhs, subqueryPlan, context, lhsReferences, null, null, false, out _, out var merge))
+                    else if (UseMergeJoin(lhs, subqueryPlan, context, lhsReferences, null, null, false, true, out _, out var merge))
                     {
                         if (unqualifiedJoin.UnqualifiedJoinType == UnqualifiedJoinType.CrossApply)
                             merge.JoinType = QualifiedJoinType.Inner;