DB2错误字符串列、主机变量、常量或函数的使用不当

我正在尝试搜索所有表和列中的某个值，并使用php连接到IBMDB2数据库。我想知道这个错误是否是由于多次使用联合引起的。

这是我的错误信息：

Improper use of a string column, host variable, constant, or function "NAMABARANG". SQLSTATE=42907 SQLCODE=-134

这是我的代码：

$keyword=$_GET['keyword'];
$query="SELECT * FROM INVENTORY WHERE NAMABARANG LIKE '%".$keyword."%'".
    " UNION ALL SELECT * FROM INVENTORY WHERE ARRIVALDATE LIKE '%".$keyword."%'".
     " UNION ALL SELECT * FROM INVENTORY WHERE PAPERNUMBER LIKE '%".$keyword."%'".
     " UNION ALL SELECT * FROM INVENTORY WHERE SERIALNUMBER LIKE '%".$keyword."%'".
     " UNION SELECT * FROM INVENTORY WHERE CONDITION LIKE '%".$keyword."%'".
     " UNION ALL SELECT * FROM INVENTORY WHERE LOCATION LIKE '%".$keyword."%'".
     " UNION ALL SELECT * FROM INVENTORY WHERE CONFIRMATIONDATE LIKE '%".$keyword."%'".
     " UNION ALL SELECT * FROM INVENTORY WHERE BARCODE LIKE '%".$keyword."%'".
     " UNION ALL SELECT * FROM USERANDPASSWORD WHERE USERNAME LIKE '%".$keyword."%'";
     " UNION ALL SELECT * FROM USERANDPASSWORD WHERE ACCESS LIKE '%".$keyword."%'";