convert BLOB to text in sql

问题

I have a field in my database table with data type as BLOB.How can I view the content as text/string using a SELECT query in SQL. the content's MIMETYPE is 'text/xml charset=UTF8'

I tried with this, I'm not sure if im right with the syntax

SELECT 
CAST((SELECT column FROM myTable WHERE ID='56')AS CHAR(10000) CHARACTER SET utf8)

and also

SELECT 
CONVERT(VARCHAR(max), CAST((SELECT column FROM myTable WHERE ID='56') 
as binary)) from BIZDOCCONTENT

many Thanks

回答1:

Try:

SELECT CONVERT(object USING utf8)
FROM tablename

回答2:

Try this query -

SELECT CONVERT(column USING utf8) FROM myTable WHERE ID=56

回答3:

I had the same problem - I just changed the field type in phpmyadmin! And what i see :

ALTER TABLE pages CHANGE content content TEXT NULL DEFAULT NULL
('content' - my field which was in BLOB-type)

回答4:

CREATE OR REPLACE FUNCTION HASTANE.getXXXXX(p_rowid in rowid) RETURN VARCHAR2
AS
    l_data long;
BEGIN
    SELECT XXXXXX INTO l_data FROM XXXXX WHERE rowid = p_rowid;
    RETURN substr(l_data, 1, 4000);
END getXXXXXX;

回答5:

Set your content type in php:

header("Content-type: image/jpg"); //Send the content Type here.
print $data['blob_data'];

来源：https://stackoverflow.com/questions/14869572/convert-blob-to-text-in-sql