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erikdarlingdata merged 1 commit into from
Apr 21, 2026
+13 −4
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Skip live query plans on Azure SQL DB (#857) #871

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4 changes: 3 additions & 1 deletion Lite/Controls/ServerTab.xaml.cs
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Original file line number Diff line number Diff line change
Expand Up @@ -5365,7 +5365,9 @@ private async void LiveSnapshot_Click(object sender, RoutedEventArgs e)
ConnectTimeout = 15
};

var query = RemoteCollectorService.BuildQuerySnapshotsQuery(supportsLiveQueryPlan: true, isAzureSqlDatabase: _isAzureSqlDatabase);
// Live query plans require VIEW SERVER PERFORMANCE STATE on Azure SQL DB,
// which DB-scoped logins don't have — skip them there. See #857.
var query = RemoteCollectorService.BuildQuerySnapshotsQuery(supportsLiveQueryPlan: !_isAzureSqlDatabase, isAzureSqlDatabase: _isAzureSqlDatabase);
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@erikdarlingdata erikdarlingdata Apr 21, 2026

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Gating logic now lives in two places — here and RemoteCollectorService.QuerySnapshots.cs:231. They agree today (!isAzureSqlDatabase), but the collector also factors version/edition (>= 13 || == 0 || == 8) while this caller only checks Azure. If the collector's predicate gets tighter later (e.g. excludes some other engine edition), this site won't follow. Consider exposing a single RemoteCollectorService.SupportsLiveQueryPlan(serverStatus) helper so both sites share the rule.

Generated by Claude Code


await using var connection = new SqlConnection(builder.ConnectionString);
await connection.OpenAsync();
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13 changes: 10 additions & 3 deletions Lite/Services/RemoteCollectorService.QuerySnapshots.cs
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Expand Up @@ -217,11 +217,18 @@ internal static string BuildQuerySnapshotsQuery(bool supportsLiveQueryPlan, bool
/// </summary>
private async Task<int> CollectQuerySnapshotsAsync(ServerConnection server, CancellationToken cancellationToken)
{
// dm_exec_query_statistics_xml requires SQL Server 2016 SP1+ (version 13)
/*
* sys.dm_exec_query_statistics_xml requires SQL Server 2016 SP1+ (version 13)
* on boxed, and VIEW SERVER PERFORMANCE STATE on Azure SQL Database regardless
* of tier. DB-scoped logins (e.g. D365FO) don't have the server-level grant
* and the DMF raises error 300 even when only called for current-DB sessions,
* so we disable live query plans on Azure SQL DB entirely. See #857.
*/
var serverStatus = _serverManager.GetConnectionStatus(server.Id);
var supportsLiveQueryPlan = serverStatus.SqlMajorVersion >= 13 || serverStatus.SqlMajorVersion == 0
|| serverStatus.SqlEngineEdition == 5 || serverStatus.SqlEngineEdition == 8;
var isAzureSqlDatabase = serverStatus.SqlEngineEdition == 5;
var supportsLiveQueryPlan = !isAzureSqlDatabase
&& (serverStatus.SqlMajorVersion >= 13 || serverStatus.SqlMajorVersion == 0
|| serverStatus.SqlEngineEdition == 8);
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@erikdarlingdata erikdarlingdata Apr 21, 2026

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Behaviour change worth calling out: previously SqlEngineEdition == 5 (Azure SQL DB) explicitly enabled live plans (the old expression OR'd EngineEdition == 5). After this change Azure SQL DB is unconditionally excluded — including service-tier/login combos where VIEW SERVER PERFORMANCE STATE is held (some elastic admin / server-admin logins can grant it). That's almost certainly the right tradeoff given #857, but it removes the capability for the small set of Azure SQL DB users who weren't broken before. The PR description's deferred test on D365FO is the right gate.

Generated by Claude Code


var query = BuildQuerySnapshotsQuery(supportsLiveQueryPlan, isAzureSqlDatabase);

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