Why type data "long blob" in mysql read as "int8" in data explorer MATLAB?

I am trying to select data in MySQL JDBC in MATLAB. One of the columns (file_data) in the table has the type "longblob". The content of the file_data is data:

The two first line are header, and the remain rows are data.

But why when I try to preview the database in database explorer in MATLAB, it should be blob, but it showed "int8".

1. Can anyone help me to solve this? so that I can get the data type longblob in MATLAB using the data in MySQL? 2. if the column "file_data" already successful change to longblob, how to read it as a table, so make me possible to process the data?