apache/shardingsphere · error · SQLFeatureNotSupportedException

updateNCharacterStream

Error message

updateNCharacterStream

What it means

The federation ResultSet throws SQLFeatureNotSupportedException("updateNCharacterStream") from updateNCharacterStream(int, Reader). This is the JDBC 4.0 national-character-set variant of positioned updates; as with all update methods in AbstractUnsupportedUpdateOperationSQLFederationResultSet, it is a final stub that always throws because SQL federation results are read-only merged snapshots with no write-back to shards.

Source

Thrown at kernel/sql-federation/core/src/main/java/org/apache/shardingsphere/sqlfederation/resultset/AbstractUnsupportedUpdateOperationSQLFederationResultSet.java:284

    
    @Override
    public final void updateCharacterStream(final String columnLabel, final Reader reader, final int length) throws SQLException {
        throw new SQLFeatureNotSupportedException("updateCharacterStream");
    }
    
    @Override
    public final void updateCharacterStream(final int columnIndex, final Reader x, final long length) throws SQLException {
        throw new SQLFeatureNotSupportedException("updateCharacterStream");
    }
    
    @Override
    public final void updateCharacterStream(final String columnLabel, final Reader reader, final long length) throws SQLException {
        throw new SQLFeatureNotSupportedException("updateCharacterStream");
    }
    
    @Override
    public final void updateNCharacterStream(final int columnIndex, final Reader x) throws SQLException {
        throw new SQLFeatureNotSupportedException("updateNCharacterStream");
    }
    
    @Override
    public final void updateNCharacterStream(final String columnLabel, final Reader x) throws SQLException {
        throw new SQLFeatureNotSupportedException("updateNCharacterStream");
    }
    
    @Override
    public final void updateNCharacterStream(final int columnIndex, final Reader x, final long length) throws SQLException {
        throw new SQLFeatureNotSupportedException("updateNCharacterStream");
    }
    
    @Override
    public final void updateNCharacterStream(final String columnLabel, final Reader x, final long length) throws SQLException {
        throw new SQLFeatureNotSupportedException("updateNCharacterStream");
    }
    
    @Override

View on GitHub (pinned to e952770a21)

Solutions

1. Write N-character data with an explicit UPDATE statement and setNCharacterStream.
2. Avoid federation routing for this query by simplifying the SQL or adjusting sharding/federation configuration.
3. Refactor update flows to statement-based writes throughout the persistence layer.

Example fix

// before
rs.updateNCharacterStream(3, nReader); // throws
rs.updateRow();

// after
PreparedStatement ps = conn.prepareStatement("UPDATE t_msg SET content = ? WHERE id = ?");
ps.setNCharacterStream(1, nReader);
ps.setLong(2, id);
ps.executeUpdate();

if (rs.getConcurrency() != ResultSet.CONCUR_UPDATABLE
        || rs instanceof org.apache.shardingsphere.sqlfederation.resultset.SQLFederationResultSet) {
    // use UPDATE + setNCharacterStream instead
}

boolean isFederationResultSet(ResultSet rs) {
    return rs instanceof org.apache.shardingsphere.sqlfederation.resultset.SQLFederationResultSet;
}

try {
    rs.updateNCharacterStream(col, reader);
} catch (SQLFeatureNotSupportedException e) {
    // fall back to PreparedStatement UPDATE with setNCharacterStream
}

When it happens

Trigger: Calling rs.updateNCharacterStream(columnIndex, reader) (no length) on a federation result set — e.g. updating an NCHAR/NVARCHAR/NCLOB-typed column of a federated query row — before rs.updateRow().

Common situations: Applications using updateNCharacterStream for Unicode text columns (common on databases with national character types); ShardingSphere deployments with SQL federation enabled; ORMs or utilities that prefer N* JDBC methods for internationalized text.

Related errors

• updateNull
• updateBoolean
• updateByte
• updateShort
• updateInt

AI-assisted analysis of apache/shardingsphere@e952770a21 (2026-08-14). Data as JSON: /api/errors/ceb13184cd3e91d9. Report an issue: GitHub.