Release v1.4.2

src/PlanViewer.App/PlanViewer.App.csproj

@@ -6,7 +6,7 @@
     <ApplicationManifest>app.manifest</ApplicationManifest>
     <ApplicationIcon>EDD.ico</ApplicationIcon>
     <AvaloniaUseCompiledBindingsByDefault>true</AvaloniaUseCompiledBindingsByDefault>
-    <Version>1.4.1</Version>
+    <Version>1.4.2</Version>
     <Authors>Erik Darling</Authors>
     <Company>Darling Data LLC</Company>
     <Product>Performance Studio</Product>

src/PlanViewer.Core/Services/PlanAnalyzer.cs

@@ -133,22 +133,72 @@
         {
             var reason = stmt.NonParallelPlanReason switch
             {
+                // User/config forced serial
                 "MaxDOPSetToOne" => "MAXDOP is set to 1",
+                "QueryHintNoParallelSet" => "OPTION (MAXDOP 1) hint forces serial execution",
+                "ParallelismDisabledByTraceFlag" => "Parallelism disabled by trace flag",
+
+                // Passive — optimizer chose serial, nothing wrong
                 "EstimatedDOPIsOne" => "Estimated DOP is 1 (the plan's estimated cost was below the cost threshold for parallelism)",
+
+                // Edition/environment limitations
                 "NoParallelPlansInDesktopOrExpressEdition" => "Express/Desktop edition does not support parallelism",
+                "NoParallelCreateIndexInNonEnterpriseEdition" => "Parallel index creation requires Enterprise edition",
+                "NoParallelPlansDuringUpgrade" => "Parallel plans disabled during upgrade",
+                "NoParallelForPDWCompilation" => "Parallel plans not supported for PDW compilation",
+                "NoParallelForCloudDBReplication" => "Parallel plans not supported during cloud DB replication",
+
+                // Query constructs that block parallelism (actionable)
                 "CouldNotGenerateValidParallelPlan" => "Optimizer could not generate a valid parallel plan. Common causes: scalar UDFs, inserts into table variables, certain system functions, or OPTION (MAXDOP 1) hints",
-                "QueryHintNoParallelSet" => "OPTION (MAXDOP 1) hint forces serial execution",
+                "TSQLUserDefinedFunctionsNotParallelizable" => "T-SQL scalar UDF prevents parallelism. Rewrite as an inline table-valued function, or on SQL Server 2019+ check if the UDF is eligible for automatic inlining",
+                "CLRUserDefinedFunctionRequiresDataAccess" => "CLR UDF with data access prevents parallelism",
+                "NonParallelizableIntrinsicFunction" => "Non-parallelizable intrinsic function in the query",
+                "TableVariableTransactionsDoNotSupportParallelNestedTransaction" => "Table variable transaction prevents parallelism. Consider using a #temp table instead",
+                "UpdatingWritebackVariable" => "Updating a writeback variable prevents parallelism",
+                "DMLQueryReturnsOutputToClient" => "DML with OUTPUT clause returning results to client prevents parallelism",
+                "MixedSerialAndParallelOnlineIndexBuildNotSupported" => "Mixed serial/parallel online index build not supported",
+                "NoRangesResumableCreate" => "Resumable index create cannot use parallelism for this operation",
+
+                // Cursor limitations
+                "NoParallelCursorFetchByBookmark" => "Cursor fetch by bookmark cannot use parallelism",
+                "NoParallelDynamicCursor" => "Dynamic cursors cannot use parallelism",
+                "NoParallelFastForwardCursor" => "Fast-forward cursors cannot use parallelism",
+
+                // Memory-optimized / natively compiled
+                "NoParallelForMemoryOptimizedTables" => "Memory-optimized tables do not support parallel plans",
+                "NoParallelForDmlOnMemoryOptimizedTable" => "DML on memory-optimized tables cannot use parallelism",
+                "NoParallelForNativelyCompiledModule" => "Natively compiled modules do not support parallelism",
+
+                // Remote queries
+                "NoParallelWithRemoteQuery" => "Remote queries cannot use parallelism",
+                "NoRemoteParallelismForMatrix" => "Remote parallelism not available for this query shape",
+
                 _ => stmt.NonParallelPlanReason
             };
 
-            // Only warn (not info) when the user explicitly forced serial execution
-            var isExplicit = stmt.NonParallelPlanReason is "MaxDOPSetToOne" or "QueryHintNoParallelSet";
+            // Actionable: user forced serial, or something in the query blocks parallelism
+            // that could potentially be rewritten. Info: passive (cost too low) or
+            // environmental (edition, upgrade, cursor type, memory-optimized).
+            var isActionable = stmt.NonParallelPlanReason is
+                "MaxDOPSetToOne" or "QueryHintNoParallelSet" or "ParallelismDisabledByTraceFlag"
+                or "CouldNotGenerateValidParallelPlan"
+                or "TSQLUserDefinedFunctionsNotParallelizable"
+                or "CLRUserDefinedFunctionRequiresDataAccess"
+                or "NonParallelizableIntrinsicFunction"
+                or "TableVariableTransactionsDoNotSupportParallelNestedTransaction"
+                or "UpdatingWritebackVariable"
+                or "DMLQueryReturnsOutputToClient"
+                or "NoParallelCursorFetchByBookmark"
+                or "NoParallelDynamicCursor"
+                or "NoParallelFastForwardCursor"
+                or "NoParallelWithRemoteQuery"
+                or "NoRemoteParallelismForMatrix";
 
             stmt.PlanWarnings.Add(new PlanWarning
             {
                 WarningType = "Serial Plan",
                 Message = $"Query running serially: {reason}.",
-                Severity = isExplicit ? PlanWarningSeverity.Warning : PlanWarningSeverity.Info
+                Severity = isActionable ? PlanWarningSeverity.Warning : PlanWarningSeverity.Info
             });
         }
 
@@ -984,7 +1034,7 @@
         // Rule 28: Row Count Spool — NOT IN with nullable column
         // Pattern: Row Count Spool with high rewinds, child scan has IS NULL predicate,
         // and statement text contains NOT IN
         if (!cfg.IsRuleDisabled(28) && node.PhysicalOp.Contains("Row Count Spool"))
         {
             var rewinds = node.HasActualStats ? (double)node.ActualRewinds : node.EstimateRewinds;
             if (rewinds > 10000 && HasNotInPattern(node, stmt))

src/PlanViewer.Web/Pages/Index.razor

@@ -7,6 +7,7 @@
         <div class="landing-content">
             <h2>Free SQL Server Query Plan Analysis</h2>
             <p class="privacy">Paste or upload a .sqlplan file. Your plan XML never leaves your browser.</p>
+            <p class="powered-by">Powered by the same analysis engine in the <a href="https://github.com/erikdarlingdata/PerformanceStudio" target="_blank" rel="noopener">Performance Studio</a> app.</p>
 
             @if (errorMessage != null)
             {

src/PlanViewer.Web/wwwroot/css/app.css

@@ -168,9 +168,25 @@ main {
     font-family: 'Montserrat', sans-serif;
     font-size: 1.05rem;
     font-weight: 600;
+    margin-bottom: 0.4rem;
+}
+
+.powered-by {
+    color: var(--text-secondary);
+    font-size: 0.9rem;
     margin-bottom: 1.5rem;
 }
 
+.powered-by a {
+    color: var(--accent);
+    text-decoration: none;
+    font-weight: 600;
+}
+
+.powered-by a:hover {
+    text-decoration: underline;
+}
+
 /* === Input Area === */
 .input-area {
     text-align: left;

src/PlanViewer.Web/wwwroot/index.html

@@ -4,6 +4,17 @@
     <meta charset="utf-8" />
     <meta name="viewport" content="width=device-width, initial-scale=1.0" />
     <title>Free SQL Server Query Plan Analysis — Darling Data</title>
+    <meta name="description" content="Free browser-based SQL Server execution plan analysis. Paste or upload a .sqlplan file — your plan XML never leaves your browser." />
+    <meta property="og:title" content="Free SQL Server Query Plan Analysis" />
+    <meta property="og:description" content="Analyze SQL Server execution plans instantly in your browser. Paste or upload a .sqlplan file — nothing to install, no data sent to a server." />
+    <meta property="og:image" content="https://plans.erikdarling.com/darling-data-logo.jpg" />
+    <meta property="og:url" content="https://plans.erikdarling.com" />
+    <meta property="og:type" content="website" />
+    <meta name="twitter:card" content="summary_large_image" />
+    <meta name="twitter:title" content="Free SQL Server Query Plan Analysis" />
+    <meta name="twitter:description" content="Analyze SQL Server execution plans instantly in your browser. Paste or upload a .sqlplan file — nothing to install, no data sent to a server." />
+    <meta name="twitter:image" content="https://plans.erikdarling.com/darling-data-logo.jpg" />
+    <link rel="icon" type="image/png" href="favicon.png" />
     <base href="/" />
     <link rel="preconnect" href="https://fonts.googleapis.com" />
     <link rel="preconnect" href="https://fonts.gstatic.com" crossorigin />