Ruby通过OCI8操作Oracle存储BLOB

摘要: 本文是一个Ruby读写Oracle的BLOB的例子，通过OCI8操作Oracle的存储过程

Oracle中BLOB是用来存储图片、文件等大数据对象的。
本文是一个Ruby读写Oracle的BLOB的例子，通过OCI8操作Oracle的存储过程

1、建表

CREATE TABLE "T_IMAGE" (
"ID" NUMBER(11) GENERATED BY DEFAULT AS IDENTITY NOT NULL ,
"IMG" BLOB NULL
)

2、写blob的存储过程

create or replace PROCEDURE P_WRITE_IMAGE
(
I_PID IN NUMBER ,
B_IMG IN BLOB
)
AS
blob_temp BLOB;
copy_amount integer;
BEGIN
insert into T_IMAGE values(I_PID,empty_blob());
commit;
select IMG into blob_temp FROM T_IMAGE where id = I_PID FOR UPDATE;
copy_amount := dbms_lob.getlength(B_IMG);
dbms_lob.copy(blob_temp, B_IMG, copy_amount);
commit;
END P_WRITE_IMAGE;

3、读blob的存储过程

CREATE OR REPLACE PROCEDURE "P_READ_IMAGE"
(
V_IMG_ID IN NUMBER,
CUR_RESULT OUT SYS_REFCURSOR
)
AS
BEGIN
OPEN CUR_RESULT FOR
SELECT ID,IMG
FROM T_IMAGE
WHERE ID=V_IMG_ID ;
END;

4、ruby写图片操作

require 'oci8'
h_conn = OCI8.new(DB_USER, DB_PASSWORD, DB_SERVER)
s_photo_full_path = "~/111.jpg"
begin
cursor = h_conn.parse('begin P_WRITE_IMAGE (
:photo_id,
:photo
); end;')
lob_photo = OCI8::BLOB.new(h_conn, File.read(s_photo_full_path, :mode => 'rb'))
cursor.bind_param(':photo_id', nil, Fixnum)
cursor.bind_param(':photo', lob_photo )
cursor.exec()
rescue OCIError
puts '-'*80
puts "Code: " + $!.code.to_s
puts "Desc: " + $!.message
puts '-'*80
end

5、ruby读图片操作

require 'oci8'
h_conn = OCI8.new(DB_USER, DB_PASSWORD, DB_SERVER)
s_photo_target_path = "~/222.jpg"
photo_id = 1
begin
cursor = h_conn.parse('begin P_READ_IMAGE(
:img_id,
:list
); end;')
cursor.bind_param(':img_id', photo_id)
cursor.bind_param(':list', nil, OCI8::Cursor)
cursor.exec()
ret_cursor = cursor[':list']
puts ret_cursor.getColNames.join(",")
while row = ret_cursor.fetch()
puts row[0]
File.open(s_photo_target_path, 'wb') do |f|
f.write(row[1].read)
end
break;
end
rescue OCIError
puts '-'*80
puts "Code: " + $!.code.to_s
puts "Desc: " + $!.message
puts '-'*80
end

参考教程

http://www.oracle.com/technetwork/cn/tutorials/rubyrails-095981-zhs.html
http://ruby-oci8.rubyforge.org/en/FAQ.html