-- ===================================================================================================================
-- SQLI-ANOM-001: Usædvanlig belastning i forhold til det normale
-- ===================================================================================================================
-- Regel-id:    SQLI-ANOM-001
-- Titel:       Usædvanlig belastning i forhold til det normale
-- Alvor:       CPU: Medium. Batch requests: Low ved stigning, Medium ved fald. Page life expectancy: Medium.
-- Versioner:   SQL Server 2005 og nyere (CPU); tællerne fra 2000.
--
-- Hvad tjekkes, og hvorfor:
--   Om belastningen er usædvanlig i forhold til, hvad der er normalt for netop denne time på ugen.
--
-- Vurdering (sker i C# ud fra de indsamlede data, ikke i SQL'en, medmindre andet er nævnt):
--   Baseline beregnes af agenten i C# fra dens EGET repository (timegennemsnit de seneste 28 dage for samme time på
--   ugen +/- 1 time, mindst 6 målepunkter) - ikke fra den overvågede server. CPU: gns. af de seneste 15 minutters
--   ProcessUtilization >= 50 % og >= middel + max(3 x std.afv., 20). Batch requests/s (forskel mellem to
--   tællermålinger): >= 100 og >= middel + max(3 x std.afv., middel) giver stigning; middel >= 50 og nu <= 30 % af
--   middel giver fald. Page life expectancy: middel >= 300 s og nu <= 30 % af middel.
--
-- Grænseværdier (konfigurationsnøgle i agentens appsettings.json og standardværdi):
--   Fast i koden (AnomalyRule og BaselineCalculator.MinSamples = 6).
--
-- Rettigheder til agentens login (se db/permissions/grant-least-privilege.sql; [agent] = agentens login):
--   GRANT VIEW SERVER STATE TO [agent];                -- SQL Server 2005-2019
--   GRANT VIEW SERVER PERFORMANCE STATE TO [agent];    -- SQL Server 2022+ (erstatter VIEW SERVER STATE)
--   GRANT VIEW SERVER SECURITY STATE TO [agent];       -- SQL Server 2022+
--   SQL Server 2000 har ikke VIEW SERVER STATE; se docs/legacy-versions.md (fx kræver DBCC SQLPERF(WAITSTATS) forhøjede rettigheder).
--
-- Data kommer fra (collector, fil : medlemmer, interval):
--   CpuCollector
--     Fil: src/SQLInsight.Collectors/Performance/CpuCollector.cs
--     Medlemmer: CpuCollector.Sql, CpuCollector.HostPlatformSql
--     Interval: 5 min som standard (SQLInsight:CollectorIntervals:cpu)
--     Delt script: SQL Scripts/_collectors/CpuCollector.sql
--   PerformanceCounterCollector
--     Fil: src/SQLInsight.Collectors/Performance/PerformanceCounterCollector.cs
--     Medlemmer: Db.StartTimeSql(version), PerformanceCounterCollector.BuildSql(dmv: true),
--     PerformanceCounterCollector.BuildSql(dmv: false)
--     Interval: 5 min som standard (SQLInsight:CollectorIntervals:performance-counters)
--     Delt script: SQL Scripts/_collectors/PerformanceCounterCollector.sql
-- Regelkode:   src/SQLInsight.Rules/Performance/AnomalyRule.cs : AnomalyRule.Evaluate
--
-- Read-only:   Ja: kun SELECT samt lokale variabler, SET-sessionsindstillinger. Intet ændrer data, indstillinger
--              eller objekter.
-- Kørsel:      Kør i SSMS som agentens login (eller et login med samme rettigheder). Hver variant er sin egen batch
--              (GO); en variant for en anden SQL Server-version end din kan fejle - det er forventet.
--              Per-database-forespørgsler er vist for databasen msdb, som findes overalt: ret navnet til den
--              database, du vil se.
-- ===================================================================================================================

-- -------------------------------------------------------------------------------------------------------------------
-- Forbindelsen: Sessionsindstillinger, agenten sætter på hver forbindelse
-- -------------------------------------------------------------------------------------------------------------------

-- Variant: Alle versioner: sættes på hver forbindelse, agenten åbner
-- Kilde: SqlConnectionFactory.SessionSettings
-- Kode:  src/SQLInsight.Connectivity/SqlConnectionFactory.cs : SqlConnectionFactory.SessionSettings
SET LOCK_TIMEOUT 5000; SET DEADLOCK_PRIORITY LOW; SET TRANSACTION ISOLATION LEVEL READ UNCOMMITTED;
GO

-- -------------------------------------------------------------------------------------------------------------------
-- CpuCollector: SQL Servers og systemets CPU-forbrug pr. minut (scheduler monitor ring buffer, op til 60 minutter).
-- -------------------------------------------------------------------------------------------------------------------

-- Variant: SQL Server 2005 og nyere
-- Kilde: CpuCollector.Sql
-- Kode:  src/SQLInsight.Collectors/Performance/CpuCollector.cs : CpuCollector.Sql
DECLARE @now_ticks bigint;
SELECT @now_ticks = ms_ticks FROM sys.dm_os_sys_info;
SELECT TOP (60)
    DATEADD(second, CAST((rb.[timestamp] - @now_ticks) / 1000 AS int), GETUTCDATE()),
    rb.record.value('(./Record/SchedulerMonitorEvent/SystemHealth/ProcessUtilization)[1]', 'int'),
    rb.record.value('(./Record/SchedulerMonitorEvent/SystemHealth/SystemIdle)[1]', 'int')
FROM (
    SELECT [timestamp], CONVERT(xml, record) AS record
    FROM sys.dm_os_ring_buffers
    WHERE ring_buffer_type = N'RING_BUFFER_SCHEDULER_MONITOR' AND record LIKE N'%<SystemHealth>%'
) rb
ORDER BY rb.[timestamp] DESC
GO

-- Variant: SQL Server 2017 og nyere (Windows eller Linux)
-- Kilde: CpuCollector.HostPlatformSql
-- Kode:  src/SQLInsight.Collectors/Performance/CpuCollector.cs : CpuCollector.HostPlatformSql
SELECT host_platform FROM sys.dm_os_host_info
GO

-- -------------------------------------------------------------------------------------------------------------------
-- PerformanceCounterCollector: Udvalgte performance counters: memory grants, page life expectancy, forbindelser,
-- blokerede processer, batch requests og kompileringer.
-- -------------------------------------------------------------------------------------------------------------------

-- Variant: SQL Server 2008 og nyere: starttidspunkt
-- Kilde: PerformanceCounterCollector.StartTimeSql(2008+)
-- Kode:  src/SQLInsight.Collectors/Db.cs : Db.StartTimeSql(version)
SELECT (SELECT sqlserver_start_time FROM sys.dm_os_sys_info)
GO

-- Variant: SQL Server 2005: starttidspunkt
-- Kilde: PerformanceCounterCollector.StartTimeSql(2005)
-- Kode:  src/SQLInsight.Collectors/Db.cs : Db.StartTimeSql(version)
SELECT (SELECT create_date FROM sys.databases WHERE database_id = 2)
GO

-- Variant: SQL Server 2000 (legacy ODBC-sti): starttidspunkt
-- Kilde: PerformanceCounterCollector.StartTimeSql(2000)
-- Kode:  src/SQLInsight.Collectors/Db.cs : Db.StartTimeSql(version)
SELECT (SELECT login_time FROM master.dbo.sysprocesses WHERE spid = 1)
GO

-- Variant: SQL Server 2005 og nyere
-- Kilde: PerformanceCounterCollector.BuildSql(dmv)
-- Kode:  src/SQLInsight.Collectors/Performance/PerformanceCounterCollector.cs : PerformanceCounterCollector.BuildSql(dmv: true)
SELECT RTRIM(object_name), RTRIM(counter_name), CAST(cntr_value AS bigint)
FROM sys.dm_os_performance_counters
WHERE (object_name LIKE N'%Memory Manager%' AND counter_name IN (N'Memory Grants Pending', N'Memory Grants Outstanding'))
   OR (object_name LIKE N'%Buffer Manager%' AND counter_name = N'Page life expectancy')
   OR (object_name LIKE N'%General Statistics%' AND counter_name IN (N'User Connections', N'Processes blocked'))
   OR (object_name LIKE N'%SQL Statistics%' AND counter_name IN (N'Batch Requests/sec', N'SQL Compilations/sec', N'SQL Re-Compilations/sec'))
GO

-- Variant: SQL Server 2000 (legacy ODBC-sti)
-- Kilde: PerformanceCounterCollector.BuildSql(sysperfinfo)
-- Kode:  src/SQLInsight.Collectors/Performance/PerformanceCounterCollector.cs : PerformanceCounterCollector.BuildSql(dmv: false)
SELECT RTRIM(object_name), RTRIM(counter_name), CAST(cntr_value AS bigint)
FROM master.dbo.sysperfinfo
WHERE (object_name LIKE N'%Memory Manager%' AND counter_name IN (N'Memory Grants Pending', N'Memory Grants Outstanding'))
   OR (object_name LIKE N'%Buffer Manager%' AND counter_name = N'Page life expectancy')
   OR (object_name LIKE N'%General Statistics%' AND counter_name IN (N'User Connections', N'Processes blocked'))
   OR (object_name LIKE N'%SQL Statistics%' AND counter_name IN (N'Batch Requests/sec', N'SQL Compilations/sec', N'SQL Re-Compilations/sec'))
GO