sqlite_udf_decode_binary Decode binary data passed as parameters to an UDF stringsqlite_udf_decode_binary stringdata sqlite_udf_decode_binary decodes the binary encoding that was applied to the parameter by either sqlite_udf_encode_binary or sqlite_escape_string. You must call this function on parameters passed to your UDF if you need them to handle binary data, as the binary encoding employed by PHP will obscure the content and of the parameter in its natural, non-coded form. PHP does not perform this encode/decode operation automatically as it would severely impact performance if it did. $context) { $context = strlen($string); } } function max_len_finalize(&$context) { return $context; } sqlite_create_aggregate($db, 'max_len', 'max_len_step', 'max_len_finalize'); var_dump(sqlite_array_query($db, 'SELECT max_len(a) from strings')); ?> ]]> See also sqlite_udf_encode_binary, sqlite_create_function and sqlite_create_aggregate.