2025

-- Traditional PostgreSQL database administration - rigid procedures with limited MongoDB applicability

-- Database performance monitoring with limited visibility
CREATE TABLE db_performance_metrics (
    metric_id UUID PRIMARY KEY DEFAULT gen_random_uuid(),
    server_name VARCHAR(100) NOT NULL,
    metric_timestamp TIMESTAMP DEFAULT CURRENT_TIMESTAMP,

    -- Connection metrics
    active_connections INTEGER,
    max_connections INTEGER,
    connection_utilization DECIMAL(5,2),
    idle_connections INTEGER,

    -- Query performance metrics
    slow_query_count INTEGER,
    average_query_time DECIMAL(10,4),
    queries_per_second DECIMAL(10,2),
    cache_hit_ratio DECIMAL(5,2),

    -- System resource utilization
    cpu_usage DECIMAL(5,2),
    memory_usage DECIMAL(5,2),
    disk_usage DECIMAL(5,2),
    io_wait DECIMAL(5,2),

    -- Database-specific metrics
    database_size BIGINT,
    index_size BIGINT,
    table_count INTEGER,
    index_count INTEGER,

    -- Lock contention
    lock_waits INTEGER,
    deadlock_count INTEGER,
    blocked_queries INTEGER,

    -- Transaction metrics
    transactions_per_second DECIMAL(10,2),
    transaction_rollback_rate DECIMAL(5,2)
);

-- Complex monitoring infrastructure with limited MongoDB compatibility
CREATE TABLE slow_query_log (
    log_id UUID PRIMARY KEY DEFAULT gen_random_uuid(),
    server_name VARCHAR(100) NOT NULL,
    database_name VARCHAR(100) NOT NULL,
    query_timestamp TIMESTAMP DEFAULT CURRENT_TIMESTAMP,

    -- Query identification
    query_hash VARCHAR(64) NOT NULL,
    query_text TEXT NOT NULL,
    normalized_query TEXT,

    -- Performance metrics
    execution_time DECIMAL(10,4) NOT NULL,
    rows_examined BIGINT,
    rows_returned BIGINT,
    index_usage TEXT,

    -- Resource consumption
    cpu_time DECIMAL(10,4),
    io_reads INTEGER,
    io_writes INTEGER,
    memory_peak BIGINT,

    -- User context
    user_name VARCHAR(100),
    application_name VARCHAR(200),
    connection_id BIGINT,
    session_id VARCHAR(100),

    -- Query categorization
    query_type VARCHAR(20), -- SELECT, INSERT, UPDATE, DELETE
    complexity_score INTEGER,
    optimization_suggestions TEXT
);

-- Maintenance scheduling with manual coordination
CREATE TABLE maintenance_schedules (
    schedule_id UUID PRIMARY KEY DEFAULT gen_random_uuid(),
    server_name VARCHAR(100) NOT NULL,
    maintenance_type VARCHAR(50) NOT NULL,
    scheduled_start TIMESTAMP NOT NULL,
    estimated_duration INTERVAL NOT NULL,

    -- Maintenance details
    maintenance_description TEXT,
    affected_databases TEXT[],
    expected_downtime INTERVAL,
    backup_required BOOLEAN DEFAULT TRUE,

    -- Approval workflow
    requested_by VARCHAR(100) NOT NULL,
    approved_by VARCHAR(100),
    approval_timestamp TIMESTAMP,
    approval_status VARCHAR(20) DEFAULT 'pending',

    -- Execution tracking
    actual_start TIMESTAMP,
    actual_end TIMESTAMP,
    execution_status VARCHAR(20) DEFAULT 'scheduled',
    execution_notes TEXT,

    -- Impact assessment
    business_impact VARCHAR(20), -- low, medium, high, critical
    user_notification_required BOOLEAN DEFAULT TRUE,
    rollback_plan TEXT
);

-- Limited backup and recovery management
CREATE TABLE backup_operations (
    backup_id UUID PRIMARY KEY DEFAULT gen_random_uuid(),
    server_name VARCHAR(100) NOT NULL,
    database_name VARCHAR(100),
    backup_timestamp TIMESTAMP DEFAULT CURRENT_TIMESTAMP,

    -- Backup configuration
    backup_type VARCHAR(20) NOT NULL, -- full, incremental, differential
    backup_method VARCHAR(20) NOT NULL, -- dump, filesystem, streaming
    compression_enabled BOOLEAN DEFAULT TRUE,
    encryption_enabled BOOLEAN DEFAULT FALSE,

    -- Backup metrics
    backup_size BIGINT,
    compressed_size BIGINT,
    backup_duration INTERVAL,

    -- Storage information
    backup_location VARCHAR(500) NOT NULL,
    storage_type VARCHAR(50), -- local, s3, nfs, tape
    retention_period INTERVAL,
    deletion_scheduled TIMESTAMP,

    -- Validation and integrity
    integrity_check_performed BOOLEAN DEFAULT FALSE,
    integrity_check_passed BOOLEAN,
    checksum VARCHAR(128),

    -- Recovery testing
    recovery_test_performed BOOLEAN DEFAULT FALSE,
    recovery_test_passed BOOLEAN,
    recovery_test_notes TEXT
);

-- Complex user access and security management
CREATE TABLE user_access_audit (
    audit_id UUID PRIMARY KEY DEFAULT gen_random_uuid(),
    server_name VARCHAR(100) NOT NULL,
    audit_timestamp TIMESTAMP DEFAULT CURRENT_TIMESTAMP,

    -- User information
    username VARCHAR(100) NOT NULL,
    user_type VARCHAR(20), -- admin, application, readonly
    authentication_method VARCHAR(50),
    source_ip INET,

    -- Access details
    operation_type VARCHAR(20) NOT NULL, -- login, logout, query, admin
    database_accessed VARCHAR(100),
    table_accessed VARCHAR(100),
    operation_details TEXT,

    -- Security context
    session_id VARCHAR(100),
    connection_duration INTERVAL,
    privilege_level VARCHAR(20),
    elevated_privileges BOOLEAN DEFAULT FALSE,

    -- Result tracking
    operation_success BOOLEAN NOT NULL,
    error_message TEXT,
    security_violation BOOLEAN DEFAULT FALSE,

    -- Risk assessment
    risk_level VARCHAR(20) DEFAULT 'low',
    anomaly_detected BOOLEAN DEFAULT FALSE,
    follow_up_required BOOLEAN DEFAULT FALSE
);

-- Manual index management with limited optimization capabilities
WITH index_analysis AS (
    SELECT 
        schemaname,
        tablename,
        indexname,
        idx_size,
        idx_tup_read,
        idx_tup_fetch,

        -- Index usage calculation
        CASE 
            WHEN idx_tup_read > 0 THEN 
                ROUND((idx_tup_fetch * 100.0 / idx_tup_read), 2)
            ELSE 0 
        END as index_efficiency,

        -- Index maintenance needs
        CASE 
            WHEN idx_tup_read < 1000 AND pg_size_pretty(idx_size::bigint) > '10 MB' THEN 'Consider removal'
            WHEN idx_tup_fetch < idx_tup_read * 0.1 THEN 'Poor selectivity'
            ELSE 'Optimal'
        END as optimization_recommendation

    FROM pg_stat_user_indexes 
    JOIN pg_indexes USING (schemaname, tablename, indexname)
),

maintenance_recommendations AS (
    SELECT 
        ia.schemaname,
        ia.tablename,
        COUNT(*) as total_indexes,
        COUNT(*) FILTER (WHERE ia.optimization_recommendation != 'Optimal') as problematic_indexes,
        array_agg(ia.indexname) FILTER (WHERE ia.optimization_recommendation = 'Consider removal') as removable_indexes,
        SUM(ia.idx_size) as total_index_size,
        AVG(ia.index_efficiency) as avg_efficiency

    FROM index_analysis ia
    GROUP BY ia.schemaname, ia.tablename
)

-- Generate maintenance recommendations
SELECT 
    mr.schemaname,
    mr.tablename,
    mr.total_indexes,
    mr.problematic_indexes,
    mr.removable_indexes,
    pg_size_pretty(mr.total_index_size::bigint) as total_size,
    ROUND(mr.avg_efficiency, 2) as avg_efficiency_percent,

    -- Maintenance priority
    CASE 
        WHEN mr.problematic_indexes > mr.total_indexes * 0.5 THEN 'High Priority'
        WHEN mr.problematic_indexes > 0 THEN 'Medium Priority'
        ELSE 'Low Priority'
    END as maintenance_priority,

    -- Specific recommendations
    CASE 
        WHEN array_length(mr.removable_indexes, 1) > 0 THEN 
            'Remove unused indexes: ' || array_to_string(mr.removable_indexes, ', ')
        WHEN mr.avg_efficiency < 50 THEN
            'Review index selectivity and query patterns'
        ELSE 
            'Continue current index strategy'
    END as detailed_recommendations

FROM maintenance_recommendations mr
WHERE mr.problematic_indexes > 0
ORDER BY mr.problematic_indexes DESC, mr.total_index_size DESC;

-- Problems with traditional database administration:
-- 1. Limited visibility into MongoDB-specific operations and performance characteristics
-- 2. Manual monitoring processes that don't scale with distributed MongoDB deployments  
-- 3. Rigid maintenance procedures that don't account for replica sets and sharding
-- 4. Backup strategies that don't leverage MongoDB's native backup capabilities
-- 5. Security management that doesn't integrate with MongoDB's role-based access control
-- 6. Performance tuning approaches that ignore MongoDB's unique optimization patterns
-- 7. Index management that doesn't understand MongoDB's compound index strategies
-- 8. Monitoring tools that lack MongoDB-specific metrics and operational insights
-- 9. Maintenance scheduling that doesn't coordinate across MongoDB cluster topology
-- 10. Recovery procedures that don't leverage MongoDB's built-in replication and failover

// MongoDB Advanced Database Administration - Enterprise monitoring and operations management
const { MongoClient, ObjectId, GridFSBucket } = require('mongodb');

const client = new MongoClient('mongodb://localhost:27017');
const db = client.db('enterprise_operations');

// Comprehensive MongoDB Database Administration Manager
class MongoDBAdministrationManager {
  constructor(client, config = {}) {
    this.client = client;
    this.db = client.db(config.database || 'enterprise_operations');

    this.collections = {
      performanceMetrics: this.db.collection('performance_metrics'),
      slowOperations: this.db.collection('slow_operations'),
      indexAnalysis: this.db.collection('index_analysis'),
      maintenanceSchedule: this.db.collection('maintenance_schedule'),
      backupOperations: this.db.collection('backup_operations'),
      userActivity: this.db.collection('user_activity'),
      systemAlerts: this.db.collection('system_alerts'),
      capacityPlanning: this.db.collection('capacity_planning')
    };

    // Administration configuration
    this.config = {
      // Monitoring configuration
      metricsCollectionInterval: config.metricsCollectionInterval || 60000, // 1 minute
      slowOperationThreshold: config.slowOperationThreshold || 100, // 100ms
      enableDetailedProfiling: config.enableDetailedProfiling !== false,
      enableRealtimeAlerts: config.enableRealtimeAlerts !== false,

      // Performance thresholds
      cpuThreshold: config.cpuThreshold || 80,
      memoryThreshold: config.memoryThreshold || 85,
      connectionThreshold: config.connectionThreshold || 80,
      diskThreshold: config.diskThreshold || 90,

      // Maintenance configuration
      enableAutomaticMaintenance: config.enableAutomaticMaintenance || false,
      maintenanceWindow: config.maintenanceWindow || { start: '02:00', end: '04:00' },
      enableMaintenanceNotifications: config.enableMaintenanceNotifications !== false,

      // Backup configuration
      enableAutomaticBackups: config.enableAutomaticBackups !== false,
      backupRetentionDays: config.backupRetentionDays || 30,
      backupSchedule: config.backupSchedule || '0 2 * * *', // 2 AM daily

      // Security and compliance
      enableSecurityAuditing: config.enableSecurityAuditing !== false,
      enableComplianceTracking: config.enableComplianceTracking || false,
      enableAccessLogging: config.enableAccessLogging !== false
    };

    // Performance monitoring state
    this.performanceMonitors = new Map();
    this.alertSubscriptions = new Map();
    this.maintenanceQueue = [];

    this.initializeAdministrationSystem();
  }

  async initializeAdministrationSystem() {
    console.log('Initializing MongoDB administration and monitoring system...');

    try {
      // Setup monitoring infrastructure
      await this.setupMonitoringInfrastructure();

      // Initialize performance tracking
      await this.initializePerformanceMonitoring();

      // Setup automated maintenance
      if (this.config.enableAutomaticMaintenance) {
        await this.initializeMaintenanceAutomation();
      }

      // Initialize backup management
      if (this.config.enableAutomaticBackups) {
        await this.initializeBackupManagement();
      }

      // Setup security auditing
      if (this.config.enableSecurityAuditing) {
        await this.initializeSecurityAuditing();
      }

      // Start monitoring processes
      await this.startMonitoringProcesses();

      console.log('MongoDB administration system initialized successfully');

    } catch (error) {
      console.error('Error initializing administration system:', error);
      throw error;
    }
  }

  async setupMonitoringInfrastructure() {
    console.log('Setting up comprehensive monitoring infrastructure...');

    try {
      // Create optimized indexes for monitoring collections
      await this.collections.performanceMetrics.createIndexes([
        { key: { timestamp: -1 }, background: true },
        { key: { serverName: 1, timestamp: -1 }, background: true },
        { key: { 'metrics.alertLevel': 1, timestamp: -1 }, background: true },
        { key: { 'metrics.cpuUsage': 1 }, background: true, sparse: true },
        { key: { 'metrics.memoryUsage': 1 }, background: true, sparse: true }
      ]);

      // Slow operations monitoring indexes
      await this.collections.slowOperations.createIndexes([
        { key: { timestamp: -1 }, background: true },
        { key: { operation: 1, timestamp: -1 }, background: true },
        { key: { duration: -1 }, background: true },
        { key: { 'context.collection': 1, timestamp: -1 }, background: true },
        { key: { 'optimization.needsAttention': 1 }, background: true, sparse: true }
      ]);

      // Index analysis tracking
      await this.collections.indexAnalysis.createIndexes([
        { key: { collection: 1, timestamp: -1 }, background: true },
        { key: { 'analysis.efficiency': 1 }, background: true },
        { key: { 'recommendations.priority': 1, timestamp: -1 }, background: true }
      ]);

      // System alerts indexing
      await this.collections.systemAlerts.createIndexes([
        { key: { timestamp: -1 }, background: true },
        { key: { severity: 1, timestamp: -1 }, background: true },
        { key: { resolved: 1, timestamp: -1 }, background: true },
        { key: { category: 1, timestamp: -1 }, background: true }
      ]);

      console.log('Monitoring infrastructure setup completed');

    } catch (error) {
      console.error('Error setting up monitoring infrastructure:', error);
      throw error;
    }
  }

  async collectComprehensiveMetrics() {
    console.log('Collecting comprehensive performance metrics...');
    const startTime = Date.now();

    try {
      // Get server status information
      const serverStatus = await this.db.admin().serverStatus();
      const dbStats = await this.db.stats();
      const currentOperations = await this.db.admin().currentOp();

      // Collect performance metrics
      const performanceMetrics = {
        _id: new ObjectId(),
        timestamp: new Date(),
        serverName: serverStatus.host,

        // Connection metrics
        connections: {
          current: serverStatus.connections.current,
          available: serverStatus.connections.available,
          totalCreated: serverStatus.connections.totalCreated,
          utilization: Math.round((serverStatus.connections.current / 
                                  (serverStatus.connections.current + serverStatus.connections.available)) * 100)
        },

        // Operation metrics
        operations: {
          insert: serverStatus.opcounters.insert,
          query: serverStatus.opcounters.query,
          update: serverStatus.opcounters.update,
          delete: serverStatus.opcounters.delete,
          getmore: serverStatus.opcounters.getmore,
          command: serverStatus.opcounters.command,

          // Operations per second calculations
          insertRate: this.calculateOperationRate('insert', serverStatus.opcounters.insert),
          queryRate: this.calculateOperationRate('query', serverStatus.opcounters.query),
          updateRate: this.calculateOperationRate('update', serverStatus.opcounters.update),
          deleteRate: this.calculateOperationRate('delete', serverStatus.opcounters.delete)
        },

        // Memory metrics
        memory: {
          resident: serverStatus.mem.resident,
          virtual: serverStatus.mem.virtual,
          mapped: serverStatus.mem.mapped || 0,
          mappedWithJournal: serverStatus.mem.mappedWithJournal || 0,

          // WiredTiger cache metrics (if available)
          cacheSizeGB: serverStatus.wiredTiger?.cache?.['maximum bytes configured'] ? 
                      Math.round(serverStatus.wiredTiger.cache['maximum bytes configured'] / 1024 / 1024 / 1024) : 0,
          cacheUsedGB: serverStatus.wiredTiger?.cache?.['bytes currently in the cache'] ? 
                      Math.round(serverStatus.wiredTiger.cache['bytes currently in the cache'] / 1024 / 1024 / 1024) : 0,
          cacheUtilization: this.calculateCacheUtilization(serverStatus)
        },

        // Database metrics
        database: {
          collections: dbStats.collections,
          objects: dbStats.objects,
          dataSize: dbStats.dataSize,
          storageSize: dbStats.storageSize,
          indexes: dbStats.indexes,
          indexSize: dbStats.indexSize,

          // Growth metrics
          avgObjSize: dbStats.avgObjSize,
          scaleFactor: dbStats.scaleFactor || 1
        },

        // Network metrics
        network: {
          bytesIn: serverStatus.network.bytesIn,
          bytesOut: serverStatus.network.bytesOut,
          numRequests: serverStatus.network.numRequests,

          // Network rates
          bytesInRate: this.calculateNetworkRate('bytesIn', serverStatus.network.bytesIn),
          bytesOutRate: this.calculateNetworkRate('bytesOut', serverStatus.network.bytesOut),
          requestRate: this.calculateNetworkRate('numRequests', serverStatus.network.numRequests)
        },

        // Current operations analysis
        activeOperations: {
          total: currentOperations.inprog.length,
          reads: currentOperations.inprog.filter(op => op.op === 'query' || op.op === 'getmore').length,
          writes: currentOperations.inprog.filter(op => op.op === 'insert' || op.op === 'update' || op.op === 'remove').length,
          commands: currentOperations.inprog.filter(op => op.op === 'command').length,

          // Long running operations
          longRunning: currentOperations.inprog.filter(op => op.microsecs_running > 1000000).length, // > 1 second
          blocked: currentOperations.inprog.filter(op => op.waitingForLock).length
        },

        // Lock metrics
        locks: this.analyzeLockMetrics(serverStatus),

        // Replication metrics (if applicable)
        replication: await this.collectReplicationMetrics(),

        // Sharding metrics (if applicable)
        sharding: await this.collectShardingMetrics(),

        // Alert evaluation
        alerts: await this.evaluatePerformanceAlerts(serverStatus, dbStats),

        // Collection metadata
        collectionTime: Date.now() - startTime,
        metricsVersion: '2.0'
      };

      // Store metrics
      await this.collections.performanceMetrics.insertOne(performanceMetrics);

      // Process alerts if any
      if (performanceMetrics.alerts.length > 0) {
        await this.processPerformanceAlerts(performanceMetrics.alerts, performanceMetrics);
      }

      console.log(`Performance metrics collected successfully: ${performanceMetrics.alerts.length} alerts generated`);

      return performanceMetrics;

    } catch (error) {
      console.error('Error collecting performance metrics:', error);
      throw error;
    }
  }

  async analyzeSlowOperations() {
    console.log('Analyzing slow operations and query performance...');

    try {
      // Get current profiling level
      const profilingLevel = await this.db.runCommand({ profile: -1 });

      // Enable profiling if not already enabled
      if (profilingLevel.was < 1) {
        await this.db.runCommand({ 
          profile: 2, // Profile all operations
          slowms: this.config.slowOperationThreshold 
        });
      }

      // Retrieve slow operations from profiler collection
      const profileData = await this.db.collection('system.profile')
        .find({
          ts: { $gte: new Date(Date.now() - 300000) }, // Last 5 minutes
          millis: { $gte: this.config.slowOperationThreshold }
        })
        .sort({ ts: -1 })
        .limit(1000)
        .toArray();

      // Analyze operations
      for (const operation of profileData) {
        const analysis = await this.analyzeOperation(operation);

        const slowOpDocument = {
          _id: new ObjectId(),
          timestamp: operation.ts,
          operation: operation.op,
          namespace: operation.ns,
          duration: operation.millis,

          // Command details
          command: operation.command,
          planSummary: operation.planSummary,
          executionStats: operation.execStats,

          // Performance analysis
          analysis: analysis,

          // Optimization recommendations
          recommendations: await this.generateOptimizationRecommendations(operation, analysis),

          // Context information
          context: {
            client: operation.client,
            user: operation.user,
            collection: this.extractCollectionName(operation.ns),
            database: this.extractDatabaseName(operation.ns)
          },

          // Impact assessment
          impact: this.assessOperationImpact(operation, analysis),

          // Tracking metadata
          analyzed: true,
          reviewRequired: analysis.complexity === 'high' || operation.millis > 5000,
          processed: new Date()
        };

        await this.collections.slowOperations.insertOne(slowOpDocument);
      }

      console.log(`Analyzed ${profileData.length} slow operations`);

      return profileData.length;

    } catch (error) {
      console.error('Error analyzing slow operations:', error);
      throw error;
    }
  }

  async performIndexAnalysis() {
    console.log('Performing comprehensive index analysis...');

    try {
      const databases = await this.client.db().admin().listDatabases();

      for (const dbInfo of databases.databases) {
        if (['admin', 'local', 'config'].includes(dbInfo.name)) continue;

        const database = this.client.db(dbInfo.name);
        const collections = await database.listCollections().toArray();

        for (const collInfo of collections) {
          const collection = database.collection(collInfo.name);

          // Get index information
          const indexes = await collection.listIndexes().toArray();
          const indexStats = await collection.aggregate([
            { $indexStats: {} }
          ]).toArray();

          // Get collection statistics
          const collStats = await collection.stats();

          // Analyze each index
          for (const index of indexes) {
            const indexStat = indexStats.find(stat => stat.name === index.name);
            const analysis = await this.analyzeIndex(index, indexStat, collStats, collection);

            const indexAnalysisDocument = {
              _id: new ObjectId(),
              timestamp: new Date(),
              database: dbInfo.name,
              collection: collInfo.name,
              indexName: index.name,

              // Index configuration
              indexSpec: index.key,
              indexOptions: {
                unique: index.unique || false,
                sparse: index.sparse || false,
                background: index.background || false,
                partialFilterExpression: index.partialFilterExpression
              },

              // Index statistics
              statistics: {
                accessCount: indexStat?.accesses?.ops || 0,
                lastAccessed: indexStat?.accesses?.since || null,
                indexSize: index.indexSizes ? index.indexSizes[index.name] : 0
              },

              // Analysis results
              analysis: analysis,

              // Performance recommendations
              recommendations: await this.generateIndexRecommendations(analysis, index, collStats),

              // Usage patterns
              usagePatterns: await this.analyzeIndexUsagePatterns(index, collection),

              // Maintenance requirements
              maintenance: {
                needsRebuild: analysis.fragmentation > 30,
                needsOptimization: analysis.efficiency < 70,
                canBeDropped: analysis.usage === 'unused' && !index.unique && index.name !== '_id_',
                priority: this.calculateMaintenancePriority(analysis)
              }
            };

            await this.collections.indexAnalysis.insertOne(indexAnalysisDocument);
          }
        }
      }

      console.log('Index analysis completed successfully');

    } catch (error) {
      console.error('Error performing index analysis:', error);
      throw error;
    }
  }

  async scheduleMaintenanceOperation(maintenanceRequest) {
    console.log('Scheduling maintenance operation...');

    try {
      const maintenanceOperation = {
        _id: new ObjectId(),
        type: maintenanceRequest.type,
        scheduledTime: maintenanceRequest.scheduledTime || new Date(),
        estimatedDuration: maintenanceRequest.estimatedDuration,

        // Operation details
        description: maintenanceRequest.description,
        targetDatabases: maintenanceRequest.databases || [],
        targetCollections: maintenanceRequest.collections || [],

        // Impact assessment
        impactLevel: maintenanceRequest.impactLevel || 'medium',
        downTimeRequired: maintenanceRequest.downTimeRequired || false,
        userNotificationRequired: maintenanceRequest.userNotificationRequired !== false,

        // Approval workflow
        requestedBy: maintenanceRequest.requestedBy,
        approvalRequired: this.determineApprovalRequirement(maintenanceRequest),
        approvalStatus: 'pending',

        // Execution planning
        executionPlan: await this.generateExecutionPlan(maintenanceRequest),
        rollbackPlan: await this.generateRollbackPlan(maintenanceRequest),
        preChecks: await this.generatePreChecks(maintenanceRequest),
        postChecks: await this.generatePostChecks(maintenanceRequest),

        // Status tracking
        status: 'scheduled',
        createdAt: new Date(),
        executedAt: null,
        completedAt: null,

        // Results tracking
        executionResults: null,
        success: null,
        notes: []
      };

      // Validate maintenance window
      const validationResult = await this.validateMaintenanceWindow(maintenanceOperation);
      if (!validationResult.valid) {
        throw new Error(`Maintenance scheduling validation failed: ${validationResult.reason}`);
      }

      // Check for conflicts
      const conflicts = await this.checkMaintenanceConflicts(maintenanceOperation);
      if (conflicts.length > 0) {
        maintenanceOperation.conflicts = conflicts;
        maintenanceOperation.status = 'conflict_detected';
      }

      // Store maintenance operation
      await this.collections.maintenanceSchedule.insertOne(maintenanceOperation);

      // Send notifications if required
      if (maintenanceOperation.userNotificationRequired) {
        await this.sendMaintenanceNotification(maintenanceOperation);
      }

      console.log(`Maintenance operation scheduled: ${maintenanceOperation._id}`, {
        type: maintenanceOperation.type,
        scheduledTime: maintenanceOperation.scheduledTime,
        impactLevel: maintenanceOperation.impactLevel
      });

      return maintenanceOperation;

    } catch (error) {
      console.error('Error scheduling maintenance operation:', error);
      throw error;
    }
  }

  async executeBackupOperation(backupConfig) {
    console.log('Executing comprehensive backup operation...');

    try {
      const backupId = new ObjectId();
      const startTime = new Date();

      const backupOperation = {
        _id: backupId,
        type: backupConfig.type || 'full',
        startTime: startTime,

        // Backup configuration
        databases: backupConfig.databases || ['all'],
        compression: backupConfig.compression !== false,
        encryption: backupConfig.encryption || false,

        // Storage configuration
        storageLocation: backupConfig.storageLocation,
        storageType: backupConfig.storageType || 'local',
        retentionDays: backupConfig.retentionDays || this.config.backupRetentionDays,

        // Backup metadata
        triggeredBy: backupConfig.triggeredBy || 'system',
        backupReason: backupConfig.reason || 'scheduled_backup',

        // Status tracking
        status: 'in_progress',
        progress: 0,
        currentDatabase: null,

        // Results placeholder
        endTime: null,
        duration: null,
        backupSize: null,
        compressedSize: null,
        success: null,
        errorMessage: null
      };

      // Store backup operation record
      await this.collections.backupOperations.insertOne(backupOperation);

      // Execute backup based on type
      let backupResults;
      switch (backupConfig.type) {
        case 'full':
          backupResults = await this.performFullBackup(backupId, backupConfig);
          break;
        case 'incremental':
          backupResults = await this.performIncrementalBackup(backupId, backupConfig);
          break;
        case 'differential':
          backupResults = await this.performDifferentialBackup(backupId, backupConfig);
          break;
        default:
          throw new Error(`Unsupported backup type: ${backupConfig.type}`);
      }

      // Update backup operation with results
      const endTime = new Date();
      await this.collections.backupOperations.updateOne(
        { _id: backupId },
        {
          $set: {
            status: backupResults.success ? 'completed' : 'failed',
            endTime: endTime,
            duration: endTime - startTime,
            backupSize: backupResults.backupSize,
            compressedSize: backupResults.compressedSize,
            success: backupResults.success,
            errorMessage: backupResults.errorMessage,
            progress: 100,

            // Backup verification
            verificationResults: backupResults.verification,
            checksumVerified: backupResults.checksumVerified,

            // Storage information
            backupFiles: backupResults.files,
            storageLocation: backupResults.storageLocation
          }
        }
      );

      // Schedule cleanup of old backups
      await this.scheduleBackupCleanup(backupId, backupConfig);

      console.log(`Backup operation completed: ${backupId}`, {
        success: backupResults.success,
        duration: endTime - startTime,
        backupSize: backupResults.backupSize
      });

      return backupResults;

    } catch (error) {
      console.error('Error executing backup operation:', error);
      throw error;
    }
  }

  // Utility methods for MongoDB administration

  calculateOperationRate(operationType, currentValue) {
    const previousMetrics = this.performanceMonitors.get(`${operationType}_previous`);
    const previousTime = this.performanceMonitors.get(`${operationType}_time`);

    if (previousMetrics && previousTime) {
      const timeDiff = (Date.now() - previousTime) / 1000; // seconds
      const valueDiff = currentValue - previousMetrics;
      const rate = Math.round(valueDiff / timeDiff);

      // Update previous values
      this.performanceMonitors.set(`${operationType}_previous`, currentValue);
      this.performanceMonitors.set(`${operationType}_time`, Date.now());

      return rate;
    } else {
      // Initialize tracking
      this.performanceMonitors.set(`${operationType}_previous`, currentValue);
      this.performanceMonitors.set(`${operationType}_time`, Date.now());
      return 0;
    }
  }

  calculateNetworkRate(metric, currentValue) {
    return this.calculateOperationRate(`network_${metric}`, currentValue);
  }

  calculateCacheUtilization(serverStatus) {
    if (serverStatus.wiredTiger?.cache) {
      const maxBytes = serverStatus.wiredTiger.cache['maximum bytes configured'];
      const currentBytes = serverStatus.wiredTiger.cache['bytes currently in the cache'];

      if (maxBytes && currentBytes) {
        return Math.round((currentBytes / maxBytes) * 100);
      }
    }
    return 0;
  }

  analyzeLockMetrics(serverStatus) {
    if (serverStatus.locks) {
      return {
        globalLock: serverStatus.locks.Global || {},
        databaseLock: serverStatus.locks.Database || {},
        collectionLock: serverStatus.locks.Collection || {},

        // Lock contention analysis
        lockContention: this.calculateLockContention(serverStatus.locks),
        lockEfficiency: this.calculateLockEfficiency(serverStatus.locks)
      };
    }
    return {};
  }

  async collectReplicationMetrics() {
    try {
      const replStatus = await this.db.admin().replSetGetStatus();

      if (replStatus.ok) {
        return {
          setName: replStatus.set,
          members: replStatus.members.length,
          primary: replStatus.members.find(m => m.stateStr === 'PRIMARY'),
          secondaries: replStatus.members.filter(m => m.stateStr === 'SECONDARY'),
          replicationLag: this.calculateReplicationLag(replStatus.members)
        };
      }
    } catch (error) {
      // Not a replica set
      return null;
    }
  }

  async collectShardingMetrics() {
    try {
      const shardingStatus = await this.db.admin().runCommand({ listShards: 1 });

      if (shardingStatus.ok) {
        return {
          shards: shardingStatus.shards.length,
          shardsInfo: shardingStatus.shards,
          balancerActive: await this.checkBalancerStatus()
        };
      }
    } catch (error) {
      // Not a sharded cluster
      return null;
    }
  }

  async evaluatePerformanceAlerts(serverStatus, dbStats) {
    const alerts = [];

    // CPU usage alert
    if (serverStatus.extra_info?.page_faults > 1000) {
      alerts.push({
        type: 'high_page_faults',
        severity: 'warning',
        message: 'High page fault rate detected',
        value: serverStatus.extra_info.page_faults,
        threshold: 1000
      });
    }

    // Connection usage alert
    const connectionUtilization = (serverStatus.connections.current / 
                                 (serverStatus.connections.current + serverStatus.connections.available)) * 100;
    if (connectionUtilization > this.config.connectionThreshold) {
      alerts.push({
        type: 'high_connection_usage',
        severity: connectionUtilization > 95 ? 'critical' : 'warning',
        message: 'High connection utilization',
        value: Math.round(connectionUtilization),
        threshold: this.config.connectionThreshold
      });
    }

    // Memory usage alerts
    if (serverStatus.mem.resident > 8000) { // > 8GB
      alerts.push({
        type: 'high_memory_usage',
        severity: 'warning',
        message: 'High resident memory usage',
        value: serverStatus.mem.resident,
        threshold: 8000
      });
    }

    return alerts;
  }

  async analyzeOperation(operation) {
    return {
      complexity: this.assessQueryComplexity(operation),
      indexUsage: this.analyzeIndexUsage(operation),
      efficiency: this.calculateQueryEfficiency(operation),
      optimization: this.identifyOptimizationOpportunities(operation)
    };
  }

  assessQueryComplexity(operation) {
    let complexity = 'low';

    if (operation.execStats?.totalDocsExamined > 10000) complexity = 'medium';
    if (operation.execStats?.totalDocsExamined > 100000) complexity = 'high';
    if (operation.planSummary?.includes('COLLSCAN')) complexity = 'high';
    if (operation.millis > 5000) complexity = 'high';

    return complexity;
  }

  analyzeIndexUsage(operation) {
    if (operation.planSummary) {
      if (operation.planSummary.includes('IXSCAN')) return 'efficient';
      if (operation.planSummary.includes('COLLSCAN')) return 'full_scan';
    }
    return 'unknown';
  }

  calculateQueryEfficiency(operation) {
    if (operation.execStats?.totalDocsExamined && operation.execStats?.totalDocsReturned) {
      const efficiency = (operation.execStats.totalDocsReturned / operation.execStats.totalDocsExamined) * 100;
      return Math.round(efficiency);
    }
    return 0;
  }
}

// Benefits of MongoDB Advanced Database Administration:
// - Comprehensive performance monitoring with real-time metrics collection and analysis
// - Automated slow operation detection and optimization recommendation generation
// - Intelligent index analysis with usage patterns and maintenance prioritization
// - Automated maintenance scheduling with conflict detection and approval workflows
// - Enterprise backup management with compression, encryption, and retention policies
// - Integrated security auditing and access control monitoring
// - Real-time alerting with configurable thresholds and escalation procedures
// - Capacity planning with growth trend analysis and resource optimization
// - High availability monitoring for replica sets and sharded clusters
// - SQL-compatible administration operations through QueryLeaf integration

module.exports = {
  MongoDBAdministrationManager
};