apache/shardingsphere · error · SQLFeatureNotSupportedException

createBlob

Error message

createBlob

What it means

ShardingSphere's JDBC driver does not implement the java.sql.Connection method createBlob (creating an empty java.sql.Blob for writing BLOB data and binding it via setBlob). The abstract base class AbstractUnsupportedOperationConnection, which ShardingSphereConnection extends, overrides it as final and unconditionally throws SQLFeatureNotSupportedException. ShardingSphere does not implement client-side LOB factories, so the method always throws. The exception is thrown the moment the method is invoked on any connection produced by the ShardingSphere Driver.

Source

Thrown at jdbc/src/main/java/org/apache/shardingsphere/driver/jdbc/unsupported/AbstractUnsupportedOperationConnection.java:94

    
    @Override
    public int getNetworkTimeout() throws SQLException {
        throw new SQLFeatureNotSupportedException("getNetworkTimeout");
    }
    
    @Override
    public void setNetworkTimeout(final Executor executor, final int milliseconds) throws SQLException {
        throw new SQLFeatureNotSupportedException("setNetworkTimeout");
    }
    
    @Override
    public Array createArrayOf(final String typeName, final Object[] elements) throws SQLException {
        throw new SQLFeatureNotSupportedException("createArrayOf");
    }
    
    @Override
    public final Blob createBlob() throws SQLException {
        throw new SQLFeatureNotSupportedException("createBlob");
    }
    
    @Override
    public Clob createClob() throws SQLException {
        throw new SQLFeatureNotSupportedException("createClob");
    }
    
    @Override
    public final NClob createNClob() throws SQLException {
        throw new SQLFeatureNotSupportedException("createNClob");
    }
    
    @Override
    public final SQLXML createSQLXML() throws SQLException {
        throw new SQLFeatureNotSupportedException("createSQLXML");
    }
    
    @Override

View on GitHub (pinned to e952770a21)

Solutions

  1. Use PreparedStatement.setBytes(int, byte[]) or setBinaryStream(int, InputStream, long) instead of a Blob object - both are routed as ordinary parameters.
  2. Use setBlob(int, InputStream, long) directly on the PreparedStatement, which avoids needing a created Blob.
  3. Only if byte-for-byte LOB semantics are required, unwrap the backend driver connection and create the Blob on it, verifying with sql-show that the parameter reaches the database intact.
Defensive patterns

Strategy: try-catch

Validate before calling

boolean supportsOp = false;
try {
    connection.getMetaData(); // connection is alive
    // JDBC has no capability flag for individual methods; probe once per JVM:
    supportsOp = probeSupport(connection); // reflective/one-time guarded call
} catch (final SQLException ignored) {
}
// Simpler and recommended: capability-check by driver URL
boolean isShardingSphere = url.startsWith("jdbc:shardingsphere:");
if (isShardingSphere) {
    // skip the unsupported call, use the alternative API path
}

Try / catch

try {
    connection.createBlob(/* args */);
} catch (final SQLFeatureNotSupportedException e) {
    // expected on ShardingSphere connections: fall back to supported API
    log.debug("Driver does not support createBlob, using fallback", e);
}

Prevention

When it happens

Trigger: Calling Connection.createBlob() on a ShardingSphere connection.

Common situations: ORMs or DAO layers that stream binary data via Blob objects (Hibernate @Lob byte[] handling in some dialects, framework LobHandler code); applications ported from drivers where createBlob is available.

Related errors

AI-assisted analysis of apache/shardingsphere@e952770a21 (2026-08-14). Data as JSON: /api/errors/ddb66ea988b549a0. Report an issue: GitHub.