hibernate/hibernate-orm · error · FunctionArgumentException

Unsupported type '%s' for function '%s()'. Only integral, de

Error message

Unsupported type '%s' for function '%s()'. Only integral, decimal and timestamp types are supported.

What it means

The final branch of GenerateSeriesArgumentValidator: only integral, decimal, and temporal JDBC types are accepted as the series bounds. A start argument of any other type — String, Boolean, UUID, enum, byte[] — throws this FunctionArgumentException stating the unsupported type and function name.

Source

Thrown at hibernate-core/src/main/java/org/hibernate/dialect/function/GenerateSeriesArgumentValidator.java:110

						)
				);
			}
			if ( stepType == null ) {
				throw unknownType( functionName, arguments, 2 );
			}
			final var stepJdbcType = ((JdbcMapping) stepType).getJdbcType();
			if ( !stepJdbcType.isInterval() && !stepJdbcType.isDuration() ) {
				throw new FunctionArgumentException(
						String.format(
								"Step parameter of function '%s()' is of type '%s', but must be of type interval",
								functionName,
								stepType.getTypeName()
						)
				);
			}
		}
		else {
			throw new FunctionArgumentException(
					String.format(
							"Unsupported type '%s' for function '%s()'. Only integral, decimal and timestamp types are supported.",
							startType.getTypeName(),
							functionName
					)
			);
		}
	}

	private FunctionArgumentException unknownType(String functionName, List<? extends SqmTypedNode<?>> arguments, int parameterIndex) {
		return new FunctionArgumentException(
				String.format(
						"Couldn't determine type of parameter %d of function '%s()'. Argument is '%s'",
						parameterIndex,
						functionName,
						arguments.get( parameterIndex )
				)
		);

View on GitHub (pinned to fad1729dce)

Solutions

Generate the character/other series in Java (loop, IntStream/Stream) and pass it as a values list or temp table instead of generate_series
Cast/convert the argument to a numeric or timestamp type before the call if the data is really numeric (cast(e.n as integer))
Bind typed parameters so validation sees numeric/temporal types

Example fix

// before
session.createQuery("select gs from generate_series(:lo, :hi) gs")
        .setParameter("lo", "1").setParameter("hi", "10"); // String bounds

// after
session.createQuery("select gs from generate_series(cast(:lo as integer), cast(:hi as integer)) gs")
        .setParameter("lo", "1").setParameter("hi", "10");

Defensive patterns

Strategy: type-guard

Validate before calling

boolean isSeriesEligible(Object bound) {
    return bound instanceof Number || bound instanceof java.time.temporal.Temporal;
}

Type guard

boolean isSeriesEligible(Object bound) {
    return bound instanceof Number || bound instanceof java.time.temporal.Temporal;
}

Try / catch

catch (FunctionArgumentException e) {
    if (e.getMessage().contains("Unsupported type")) {
        return generateSeriesInJava(lo, hi); // fallback for non-numeric series
    }
    throw e;
}

Prevention

Generate non-numeric series (letters, codes) in application code, not via generate_series
Bind parameters with explicit numeric/temporal type classes
Validate user-supplied series bounds against a whitelist before composing HQL

When it happens

Trigger: generate_series('a','z') (String bounds), generate_series(:ids) with UUID parameters, or passing an enum/bit field; also arises when bind parameters are untyped/null at validation time so their expressible resolves to a non-numeric type.

Common situations: Trying to generate character series like PostgreSQL's generate_series('a','z'); dynamic queries where the first argument is user-controlled and can be non-numeric; criteria code reusing a generic series helper with the wrong parameter type.

Related errors

AI-assisted analysis of hibernate/hibernate-orm@fad1729dce (2026-08-22). Data as JSON: /api/errors/8f343332d99fb10e. Report an issue: GitHub.