Dear All,
i am using apex 5.1 on oracle 12c with windows environment on mozila firefox.
my question is of a beginner, but i am stuck.
i want to upload and download files in apex 5.1.
after searching the google, i thought to open a thread.
i have created on form and it give an error.

look at me blob column settings

table structure is below
CREATE TABLE "TASK_TRACKER"."EIU_FILES"
( "FILE_ID" NUMBER GENERATED BY DEFAULT ON NULL AS IDENTITY MINVALUE 1 MAXVALUE 9999999999999999999999999999 INCREMENT BY 1 START WITH 1 CACHE 20 NOORDER NOCYCLE NOT NULL ENABLE,
"FILENAME" VARCHAR2(4000 BYTE),
"FILE\_MIMETYPE" VARCHAR2(512 BYTE),
"FILE\_CHARSET" VARCHAR2(512 BYTE),
"FILE\_BLOB" BLOB,
"CREATED" TIMESTAMP (6) WITH LOCAL TIME ZONE,
"EE\_SEC\_PROGREES\_ID" NUMBER);
am i missing any setting or any code?
thank you.