/**
* MySQL Resource - sys Schema
*/
import type { MySQLAdapter } from '../MySQLAdapter.js';
import type { ResourceDefinition, RequestContext } from '../../../types/index.js';
export function createSysSchemaResource(adapter: MySQLAdapter): ResourceDefinition {
return {
uri: 'mysql://sysschema',
name: 'sys Schema Diagnostics',
title: 'MySQL sys Schema Summary',
description: 'Key diagnostic information from MySQL sys schema views',
mimeType: 'application/json',
annotations: {
audience: ['user', 'assistant'],
priority: 0.7
},
handler: async (_uri: string, _context: RequestContext) => {
try {
// Top resource consumers
const usersResult = await adapter.executeQuery(`
SELECT user, total_connections, current_connections,
total_memory_allocated as memory_bytes
FROM sys.user_summary
ORDER BY total_memory_allocated DESC
LIMIT 5
`);
// Slow statements
const statementsResult = await adapter.executeQuery(`
SELECT SUBSTRING(query, 1, 100) as query_preview,
exec_count, total_latency, avg_latency
FROM sys.statements_with_runtimes_in_95th_percentile
LIMIT 5
`);
// Current lock waits
const locksResult = await adapter.executeQuery(`
SELECT COUNT(*) as lock_wait_count FROM sys.innodb_lock_waits
`);
const lockRow = locksResult.rows?.[0];
return {
available: true,
topUsers: usersResult.rows ?? [],
slowStatements: statementsResult.rows ?? [],
currentLockWaits: Number(lockRow?.['lock_wait_count'] ?? 0)
};
} catch {
return {
available: false,
message: 'sys schema not available or insufficient privileges'
};
}
}
};
}
