如何使用 Python Flask 将图像文件上传到 oracle 数据库

Question

I am trying to update a row in my oracle database with a image file (into a blob column) and the file name (varchar2 column).

Below is my code, if I put f.filename in the parenthesis of f.read() , then I get error " expecting a integer as parameter " and if I put nothing there then I get " cx_Oracle.DatabaseError: ORA-01036: illegal variable name/number " on cur.execute line.

How do I modify the below code update the row with my image file? Thanks. I am new to python and trying to learn on my own.

    v_sql = "update login_table set image_file= %s and binary_file = %s where email_address= %s"            
    v_binary_file = f.read() 
    v_current_user = 'abcd@abcd.com'
    v_args = (f.filename, v_binary_file, v_current_user)
    cur.execute(v_sql, v_args)
    cur.commit

Answer 1

Oracle's bind variable syntax uses a colon (':') not a percent ('%') prefix for statement placeholders.

The cx_Oracle manual LOB documentation has clear LOB examples:

with open('example.txt', 'r') as f:
    textdata = f.read()

with open('image.png', 'rb') as f:
    imgdata = f.read()

cursor.execute("""
        insert into lob_tbl (id, c, b)
        values (:lobid, :clobdata, :blobdata)""",
        lobid=10, clobdata=textdata, blobdata=imgdata)