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{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"diagnostics_channel: invalid sqlite.db.query subscription activates native tracing","articleBody":"### Version\n\nmain\n\n### Platform\n\n```text\nN/A\n```\n\n### Subsystem\n\ndiagnostics_channel\n\n### What steps will reproduce the bug?\n\n```js\nimport { channel, subscribe } from 'node:diagnostics_channel';\nimport { DatabaseSync } from 'node:sqlite';\n\nconst ch = channel('sqlite.db.query');\nconst db = new DatabaseSync(':memory:');\n\nconsole.log('before:', ch.hasSubscribers);\n\ntry {\n  subscribe('sqlite.db.query', null);\n} catch (error) {\n  console.log('caught:', error.code);\n}\n\nconsole.log('after:', ch.hasSubscribers);\n\n// This query enters the unnecessarily installed native trace callback.\ndb.exec('SELECT 1');\ndb.close();\n```\n\n### How often does it reproduce? Is there a required condition?\n\nAlways\n\n### What is the expected behavior? Why is that the expected behavior?\n\nThe invalid callback should be rejected before the channel becomes active or native modules are notified, and `hasSubscribers` should remain `false`.\n\n### What do you see instead?\n\n```console\nbefore: false\ncaught: ERR_INVALID_ARG_TYPE\nafter: true\n```\n\nA rejected subscription changes `hasSubscribers` from `false` to `true` even though no callback was installed.\n\n### Additional information\n\n_No response_","author":{"url":"https://github.com/trivikr","@type":"Person","name":"trivikr"},"datePublished":"2026-08-15T21:12:49Z","url":"https://github.com/nodejs/node/issues/65312"}