Error
Error Code:
22038
PostgreSQL Error 22038: Singleton JSON Item Required
Description
This error indicates that a SQL/JSON function or operator expected a single JSON item (a scalar value, object, or array) but received multiple items, an empty set, or an invalid structure in a context requiring a singleton. It typically occurs when processing JSON data where a specific part of the query expects to extract or operate on a single, unambiguous JSON element.
Error Message
singleton sql json item required
Known Causes
3 known causesJSON Path Returns Multiple Values
A SQL/JSON path expression evaluated to multiple items when the context (e.g., `json_value` with `RETURNING SCALAR`) expected only a single scalar result.
Incorrect Scalar Extraction
Attempting to extract a scalar value using a function or operator from a JSON array or object that does not directly contain a single scalar item in the expected location.
Ambiguous JSON Input
Providing JSON data to a function that expects a single, unambiguous JSON item (e.g., a single object or value), but the input contains multiple top-level items or an unexpected structure.
Solutions
Coming SoonDetailed step-by-step solutions for this error are being prepared. In the meantime, try these general troubleshooting tips:
General Troubleshooting Tips
- Check the error message carefully for specific details
- Review recent changes that might have caused the error
- Search for the exact error code in the official documentation
- Check log files for additional context
- Try restarting the application or service