presto-parquet/src/main/java/io/prestosql/parquet/ParquetTypeUtils.java/ParquetTypeUtils/getParquetTypeByName
class ParquetTypeUtils:    public static org.apache.parquet.schema.Type getParquetTypeByName(String columnName, MessageType messageType)
    {
        if (messageType.containsField(columnName)) {
            return messageType.getType(columnName);
        }
        // parquet is case-sensitive, but hive is not. all hive columns get converted to lowercase
        // check for direct match above but if no match found, try case-insensitive match
        for (org.apache.parquet.schema.Type type : messageType.getFields()) {
            if (type.getName().equalsIgnoreCase(columnName)) {
                return type;
            }
        }

        return null;
    }