prestodb/presto · error · IllegalArgumentException

Invalid VARCHAR length {length}

Error message

Invalid VARCHAR length {length}

What it means

AbstractVarcharType's package-private constructor validates that the VARCHAR length is non-negative before creating the type, throwing IllegalArgumentException for negative lengths. VARCHAR types in Presto carry a maximum length; only createVarcharType with length >= 0 (or unbounded VARCHAR) is valid.

Source

Thrown at presto-common/src/main/java/com/facebook/presto/common/type/AbstractVarcharType.java:38

import io.airlift.slice.Slice;
import io.airlift.slice.Slices;

import java.util.Objects;

public class AbstractVarcharType
        extends AbstractVariableWidthType
{
    public static final int UNBOUNDED_LENGTH = Integer.MAX_VALUE;
    public static final int MAX_LENGTH = Integer.MAX_VALUE - 1;

    private final int length;

    AbstractVarcharType(int length, TypeSignature typeSignature)
    {
        super(typeSignature, Slice.class);

        if (length < 0) {
            throw new IllegalArgumentException("Invalid VARCHAR length " + length);
        }
        this.length = length;
    }

    @Deprecated
    public int getLength()
    {
        return length;
    }

    public int getLengthSafe()
    {
        if (isUnbounded()) {
            throw new IllegalStateException("Cannot get size of unbounded VARCHAR.");
        }
        return length;
    }

View on GitHub (pinned to 55bb57d202)

Solutions

1. Pass VARCHAR_LENGTH (unbounded) or a non-negative length to createVarcharType; use createUnboundedVarcharType for unbounded
2. Treat sentinel values like -1 from metadata as unbounded and map them to unbounded VARCHAR before constructing
3. Validate parsed length values (n >= 0) before type construction
4. Clamp/fix length arithmetic that can underflow

Example fix

// before
VarcharType type = VarcharType.createVarcharType(metadataLength); // -1 sentinel
// after
VarcharType type = metadataLength < 0
    ? VarcharType.createUnboundedVarcharType()
    : VarcharType.createVarcharType(metadataLength);

if (length < 0) {
    throw new IllegalArgumentException("VARCHAR length must be >= 0, got " + length);
}
VarcharType t = VarcharType.createVarcharType(length);

boolean isValidVarcharLength(int length) { return length >= 0; }

try { type = VarcharType.createVarcharType(len); } catch (IllegalArgumentException e) { type = VarcharType.createUnboundedVarcharType(); }

When it happens

Trigger: Calling createVarcharType(length) with a negative length, e.g. from unbounded metadata, a length parsed from a bad DDL/type signature, or an int underflow when computing lengths.

Common situations: Connector metadata returning -1 or another sentinel for 'unbounded' length; parsing VARCHAR(n) from config where n is missing/negative; arithmetic on lengths that overflows to negative.

Understand the failure class

Background: "Must be a positive integer", "Invalid value", "Unsupported": the invalid-argument-value error family, when a library rejects the value you pass — this error's family across 35 libraries.

Related errors

• Expected VarcharType but got {type.getClass().getName()}
• Expected exactly one parameter for VARCHAR
• VARCHAR length must be a number
• Invalid day-time interval:
• Invalid year-month interval:

AI-assisted analysis of prestodb/presto@55bb57d202 (2026-09-04). Data as JSON: /api/errors/bb1a3ad6dcaee389. Report an issue: GitHub.