-- C Nostr Relay Database Schema
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-- SQLite schema for storing Nostr events with JSON tags support
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-- Configuration system using config table
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-- Schema version tracking
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PRAGMA user_version = 7;
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-- Enable foreign key support
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PRAGMA foreign_keys = ON;
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-- Optimize for performance
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PRAGMA journal_mode = WAL;
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PRAGMA synchronous = NORMAL;
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PRAGMA cache_size = 10000;
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-- Core events table with hybrid single-table design
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CREATE TABLE events (
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    id TEXT PRIMARY KEY,                -- Nostr event ID (hex string)
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    pubkey TEXT NOT NULL,               -- Public key of event author (hex string)
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    created_at INTEGER NOT NULL,       -- Event creation timestamp (Unix timestamp)
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    kind INTEGER NOT NULL,              -- Event kind (0-65535)
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    event_type TEXT NOT NULL CHECK (event_type IN ('regular', 'replaceable', 'ephemeral', 'addressable')),
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    content TEXT NOT NULL,              -- Event content (text content only)
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    sig TEXT NOT NULL,                  -- Event signature (hex string)
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    tags JSON NOT NULL DEFAULT '[]',   -- Event tags as JSON array
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    first_seen INTEGER NOT NULL DEFAULT (strftime('%s', 'now'))  -- When relay received event
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);
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-- Core performance indexes
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CREATE INDEX idx_events_pubkey ON events(pubkey);
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CREATE INDEX idx_events_kind ON events(kind);
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CREATE INDEX idx_events_created_at ON events(created_at DESC);
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CREATE INDEX idx_events_event_type ON events(event_type);
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-- Composite indexes for common query patterns
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CREATE INDEX idx_events_kind_created_at ON events(kind, created_at DESC);
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CREATE INDEX idx_events_pubkey_created_at ON events(pubkey, created_at DESC);
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CREATE INDEX idx_events_pubkey_kind ON events(pubkey, kind);
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-- Schema information table
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CREATE TABLE schema_info (
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    key TEXT PRIMARY KEY,
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    value TEXT NOT NULL,
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    updated_at INTEGER NOT NULL DEFAULT (strftime('%s', 'now'))
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);
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-- Insert schema metadata
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INSERT INTO schema_info (key, value) VALUES
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    ('version', '7'),
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    ('description', 'Hybrid Nostr relay schema with event-based and table-based configuration'),
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    ('created_at', strftime('%s', 'now'));
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-- Helper views for common queries
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CREATE VIEW recent_events AS
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SELECT id, pubkey, created_at, kind, event_type, content
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FROM events
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WHERE event_type != 'ephemeral'
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ORDER BY created_at DESC
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LIMIT 1000;
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CREATE VIEW event_stats AS
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SELECT 
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    event_type,
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    COUNT(*) as count,
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    AVG(length(content)) as avg_content_length,
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    MIN(created_at) as earliest,
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    MAX(created_at) as latest
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FROM events
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GROUP BY event_type;
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-- Configuration events view (kind 33334)
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CREATE VIEW configuration_events AS
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SELECT 
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    id,
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    pubkey as admin_pubkey,
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    created_at,
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    content,
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    tags,
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    sig
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FROM events
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WHERE kind = 33334
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ORDER BY created_at DESC;
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-- Optimization: Trigger for automatic cleanup of ephemeral events older than 1 hour
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CREATE TRIGGER cleanup_ephemeral_events
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    AFTER INSERT ON events
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    WHEN NEW.event_type = 'ephemeral'
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BEGIN
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    DELETE FROM events 
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    WHERE event_type = 'ephemeral' 
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    AND first_seen < (strftime('%s', 'now') - 3600);
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END;
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-- Replaceable event handling trigger
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CREATE TRIGGER handle_replaceable_events
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    AFTER INSERT ON events
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    WHEN NEW.event_type = 'replaceable'
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BEGIN
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    DELETE FROM events 
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    WHERE pubkey = NEW.pubkey 
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    AND kind = NEW.kind 
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    AND event_type = 'replaceable'
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    AND id != NEW.id;
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END;
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-- Addressable event handling trigger (for kind 33334 configuration events)
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CREATE TRIGGER handle_addressable_events
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    AFTER INSERT ON events
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    WHEN NEW.event_type = 'addressable'
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BEGIN
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    -- For kind 33334 (configuration), replace previous config from same admin
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    DELETE FROM events 
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    WHERE pubkey = NEW.pubkey 
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    AND kind = NEW.kind 
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    AND event_type = 'addressable'
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    AND id != NEW.id;
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END;
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-- Relay Private Key Secure Storage
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-- Stores the relay's private key separately from public configuration
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CREATE TABLE relay_seckey (
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    private_key_hex TEXT NOT NULL CHECK (length(private_key_hex) = 64),
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    created_at INTEGER NOT NULL DEFAULT (strftime('%s', 'now'))
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);
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-- Authentication Rules Table for NIP-42 and Policy Enforcement
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-- Used by request_validator.c for unified validation
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CREATE TABLE auth_rules (
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    id INTEGER PRIMARY KEY AUTOINCREMENT,
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    rule_type TEXT NOT NULL CHECK (rule_type IN ('whitelist', 'blacklist', 'rate_limit', 'auth_required')),
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    pattern_type TEXT NOT NULL CHECK (pattern_type IN ('pubkey', 'kind', 'ip', 'global')),
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    pattern_value TEXT,
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    action TEXT NOT NULL CHECK (action IN ('allow', 'deny', 'require_auth', 'rate_limit')),
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    parameters TEXT, -- JSON parameters for rate limiting, etc.
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    active INTEGER NOT NULL DEFAULT 1,
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    created_at INTEGER NOT NULL DEFAULT (strftime('%s', 'now')),
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    updated_at INTEGER NOT NULL DEFAULT (strftime('%s', 'now'))
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);
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-- Indexes for auth_rules performance
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CREATE INDEX idx_auth_rules_pattern ON auth_rules(pattern_type, pattern_value);
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CREATE INDEX idx_auth_rules_type ON auth_rules(rule_type);
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CREATE INDEX idx_auth_rules_active ON auth_rules(active);
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-- Configuration Table for Table-Based Config Management
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-- Hybrid system supporting both event-based and table-based configuration
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CREATE TABLE config (
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    key TEXT PRIMARY KEY,
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    value TEXT NOT NULL,
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    data_type TEXT NOT NULL CHECK (data_type IN ('string', 'integer', 'boolean', 'json')),
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    description TEXT,
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    category TEXT DEFAULT 'general',
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    requires_restart INTEGER DEFAULT 0,
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    created_at INTEGER NOT NULL DEFAULT (strftime('%s', 'now')),
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    updated_at INTEGER NOT NULL DEFAULT (strftime('%s', 'now'))
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);
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-- Indexes for config table performance
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CREATE INDEX idx_config_category ON config(category);
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CREATE INDEX idx_config_restart ON config(requires_restart);
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CREATE INDEX idx_config_updated ON config(updated_at DESC);
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-- Trigger to update config timestamp on changes
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CREATE TRIGGER update_config_timestamp
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    AFTER UPDATE ON config
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    FOR EACH ROW
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BEGIN
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    UPDATE config SET updated_at = strftime('%s', 'now') WHERE key = NEW.key;
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END;
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-- Insert default configuration values
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INSERT INTO config (key, value, data_type, description, category, requires_restart) VALUES
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    ('relay_description', 'A C Nostr Relay', 'string', 'Relay description', 'general', 0),
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    ('relay_contact', '', 'string', 'Relay contact information', 'general', 0),
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    ('relay_software', 'https://github.com/laanwj/c-relay', 'string', 'Relay software URL', 'general', 0),
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    ('relay_version', '1.0.0', 'string', 'Relay version', 'general', 0),
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    ('relay_port', '8888', 'integer', 'Relay port number', 'network', 1),
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    ('max_connections', '1000', 'integer', 'Maximum concurrent connections', 'network', 1),
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    ('auth_enabled', 'false', 'boolean', 'Enable NIP-42 authentication', 'auth', 0),
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    ('nip42_auth_required_events', 'false', 'boolean', 'Require auth for event publishing', 'auth', 0),
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    ('nip42_auth_required_subscriptions', 'false', 'boolean', 'Require auth for subscriptions', 'auth', 0),
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    ('nip42_auth_required_kinds', '[]', 'json', 'Event kinds requiring authentication', 'auth', 0),
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    ('nip42_challenge_expiration', '600', 'integer', 'Auth challenge expiration seconds', 'auth', 0),
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    ('pow_min_difficulty', '0', 'integer', 'Minimum proof-of-work difficulty', 'validation', 0),
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    ('pow_mode', 'optional', 'string', 'Proof-of-work mode', 'validation', 0),
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    ('nip40_expiration_enabled', 'true', 'boolean', 'Enable event expiration', 'validation', 0),
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    ('nip40_expiration_strict', 'false', 'boolean', 'Strict expiration mode', 'validation', 0),
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    ('nip40_expiration_filter', 'true', 'boolean', 'Filter expired events in queries', 'validation', 0),
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    ('nip40_expiration_grace_period', '60', 'integer', 'Expiration grace period seconds', 'validation', 0),
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    ('max_subscriptions_per_client', '25', 'integer', 'Maximum subscriptions per client', 'limits', 0),
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    ('max_total_subscriptions', '1000', 'integer', 'Maximum total subscriptions', 'limits', 0),
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    ('max_filters_per_subscription', '10', 'integer', 'Maximum filters per subscription', 'limits', 0),
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    ('max_event_tags', '2000', 'integer', 'Maximum tags per event', 'limits', 0),
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    ('max_content_length', '100000', 'integer', 'Maximum event content length', 'limits', 0),
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    ('max_message_length', '131072', 'integer', 'Maximum WebSocket message length', 'limits', 0),
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    ('default_limit', '100', 'integer', 'Default query limit', 'limits', 0),
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    ('max_limit', '5000', 'integer', 'Maximum query limit', 'limits', 0);
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-- Persistent Subscriptions Logging Tables (Phase 2)
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-- Optional database logging for subscription analytics and debugging
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-- Subscription events log
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CREATE TABLE subscription_events (
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    id INTEGER PRIMARY KEY AUTOINCREMENT,
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    subscription_id TEXT NOT NULL,           -- Subscription ID from client
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    client_ip TEXT NOT NULL,                 -- Client IP address
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    event_type TEXT NOT NULL CHECK (event_type IN ('created', 'closed', 'expired', 'disconnected')),
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    filter_json TEXT,                        -- JSON representation of filters (for created events)
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    events_sent INTEGER DEFAULT 0,           -- Number of events sent to this subscription
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    created_at INTEGER NOT NULL DEFAULT (strftime('%s', 'now')),
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    ended_at INTEGER,                        -- When subscription ended (for closed/expired/disconnected)
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    duration INTEGER                         -- Computed: ended_at - created_at
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);
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-- Subscription metrics summary
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CREATE TABLE subscription_metrics (
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    id INTEGER PRIMARY KEY AUTOINCREMENT,
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    date TEXT NOT NULL,                      -- Date (YYYY-MM-DD)
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    total_created INTEGER DEFAULT 0,         -- Total subscriptions created
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    total_closed INTEGER DEFAULT 0,          -- Total subscriptions closed
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    total_events_broadcast INTEGER DEFAULT 0, -- Total events broadcast
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    avg_duration REAL DEFAULT 0,            -- Average subscription duration
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    peak_concurrent INTEGER DEFAULT 0,       -- Peak concurrent subscriptions
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    updated_at INTEGER NOT NULL DEFAULT (strftime('%s', 'now')),
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    UNIQUE(date)
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);
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-- Event broadcasting log (optional, for detailed analytics)
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CREATE TABLE event_broadcasts (
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    id INTEGER PRIMARY KEY AUTOINCREMENT,
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    event_id TEXT NOT NULL,                  -- Event ID that was broadcast
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    subscription_id TEXT NOT NULL,           -- Subscription that received it
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    client_ip TEXT NOT NULL,                 -- Client IP
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    broadcast_at INTEGER NOT NULL DEFAULT (strftime('%s', 'now')),
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    FOREIGN KEY (event_id) REFERENCES events(id)
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);
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-- Indexes for subscription logging performance
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CREATE INDEX idx_subscription_events_id ON subscription_events(subscription_id);
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CREATE INDEX idx_subscription_events_type ON subscription_events(event_type);
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CREATE INDEX idx_subscription_events_created ON subscription_events(created_at DESC);
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CREATE INDEX idx_subscription_events_client ON subscription_events(client_ip);
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CREATE INDEX idx_subscription_metrics_date ON subscription_metrics(date DESC);
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CREATE INDEX idx_event_broadcasts_event ON event_broadcasts(event_id);
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CREATE INDEX idx_event_broadcasts_sub ON event_broadcasts(subscription_id);
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CREATE INDEX idx_event_broadcasts_time ON event_broadcasts(broadcast_at DESC);
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-- Trigger to update subscription duration when ended
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CREATE TRIGGER update_subscription_duration
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    AFTER UPDATE OF ended_at ON subscription_events
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    WHEN NEW.ended_at IS NOT NULL AND OLD.ended_at IS NULL
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BEGIN
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    UPDATE subscription_events
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    SET duration = NEW.ended_at - NEW.created_at
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    WHERE id = NEW.id;
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END;
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-- View for subscription analytics
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CREATE VIEW subscription_analytics AS
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SELECT
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    date(created_at, 'unixepoch') as date,
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    COUNT(*) as subscriptions_created,
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    COUNT(CASE WHEN ended_at IS NOT NULL THEN 1 END) as subscriptions_ended,
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    AVG(CASE WHEN duration IS NOT NULL THEN duration END) as avg_duration_seconds,
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    MAX(events_sent) as max_events_sent,
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    AVG(events_sent) as avg_events_sent,
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    COUNT(DISTINCT client_ip) as unique_clients
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FROM subscription_events
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GROUP BY date(created_at, 'unixepoch')
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ORDER BY date DESC;
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-- View for current active subscriptions (from log perspective)
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CREATE VIEW active_subscriptions_log AS
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SELECT
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    subscription_id,
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    client_ip,
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    filter_json,
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    events_sent,
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    created_at,
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    (strftime('%s', 'now') - created_at) as duration_seconds
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FROM subscription_events
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WHERE event_type = 'created'
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AND subscription_id NOT IN (
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    SELECT subscription_id FROM subscription_events
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    WHERE event_type IN ('closed', 'expired', 'disconnected')
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);
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-- Database Statistics Views for Admin API
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-- Event kinds distribution view
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CREATE VIEW event_kinds_view AS
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SELECT
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    kind,
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    COUNT(*) as count,
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    ROUND(COUNT(*) * 100.0 / (SELECT COUNT(*) FROM events), 2) as percentage
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FROM events
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GROUP BY kind
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ORDER BY count DESC;
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-- Top pubkeys by event count view
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CREATE VIEW top_pubkeys_view AS
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SELECT
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    pubkey,
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    COUNT(*) as event_count,
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    ROUND(COUNT(*) * 100.0 / (SELECT COUNT(*) FROM events), 2) as percentage
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FROM events
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GROUP BY pubkey
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ORDER BY event_count DESC
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LIMIT 10;
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-- Time-based statistics view
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CREATE VIEW time_stats_view AS
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SELECT
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    'total' as period,
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    COUNT(*) as total_events,
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    COUNT(DISTINCT pubkey) as unique_pubkeys,
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    MIN(created_at) as oldest_event,
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    MAX(created_at) as newest_event
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FROM events
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UNION ALL
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SELECT
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    '24h' as period,
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    COUNT(*) as total_events,
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    COUNT(DISTINCT pubkey) as unique_pubkeys,
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    MIN(created_at) as oldest_event,
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    MAX(created_at) as newest_event
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FROM events
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WHERE created_at >= (strftime('%s', 'now') - 86400)
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UNION ALL
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SELECT
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    '7d' as period,
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    COUNT(*) as total_events,
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    COUNT(DISTINCT pubkey) as unique_pubkeys,
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    MIN(created_at) as oldest_event,
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    MAX(created_at) as newest_event
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FROM events
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WHERE created_at >= (strftime('%s', 'now') - 604800)
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UNION ALL
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SELECT
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    '30d' as period,
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    COUNT(*) as total_events,
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    COUNT(DISTINCT pubkey) as unique_pubkeys,
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    MIN(created_at) as oldest_event,
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    MAX(created_at) as newest_event
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FROM events
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WHERE created_at >= (strftime('%s', 'now') - 2592000);

#endif /* SQL_SCHEMA_H */