How to load a file into database column?


While some other database systems might have an SQL function for this, with Firebird you need an application. Datatype that holds binary files is called BLOB, and you should use sub_type zero, as sub_type one is for text-only data. Let's create a table to hold the file. We'll have a filename column and a blob column containing the file itself:

CREATE TABLE t1
(
file_name VARCHAR(200),
file_data BLOB SUB_TYPE 0
);

The blobs are loaded via parametrized query:

INSERT INTO t1 (file_name, file_data) VALUES (?, ?);

Now use your favorite programming language to set the parameters. Here's a short C++ example using IBPP library:

// previously setup variables
IBPP::Database db;
IBPP::Transaction tr;
IBPP::Statement st;
std::string file_content; // loaded from file: myfile.pdf

// writing file data to Blob column
st->Prepare("INSERT INTO t1 (file_name, file_data) VALUES (?, ?)");
st->Set(1, "myfile.pdf");
IBPP::Blob b = IBPP::BlobFactory(db, tr);
b->Save(file_content);
st->Set(2, b);
st->Execute();


Here's an example how to update a BLOB field using PHP:

ibase_connect($database, $user, $password) or die(ibase_errmsg());
$fd = fopen('myfile2.pdf', 'r');
$blob = ibase_blob_import($fd);
fclose($fd);
ibase_query("update table1 set blob_field = ?", $blob)
or die(ibase_errmsg());


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