SQLite3::openBlob
(PHP 5 >= 5.3.0, PHP 7, PHP 8)
Opens a stream resource to read a BLOB
Description
Opens a stream resource to read or write a BLOB, which would be selected by:
SELECT column FROM database.table WHERE rowid = rowid
It is not possible to change the size of a BLOB by writing to the stream. Instead, an UPDATE statement has to be executed, possibly using SQLite's zeroblob() function to set the desired BLOB size.
Parameters
tableThe table name.
columnThe column name.
rowidThe row ID.
databaseThe symbolic name of the DB
flagsEither
SQLITE3_OPEN_READONLYorSQLITE3_OPEN_READWRITEto open the stream for reading only, or for reading and writing, respectively.
Return Values
Returns a stream resource, Falseforfailure.
Changelog
| Version | Description |
|---|---|
| 7.2.0 | The flags parameter has been added, allowing to write BLOBs; formerly only reading was supported. |
Examples
SQLite3::openBlob() example
<?php
$conn = new SQLite3(':memory:');
$conn->exec('CREATE TABLE test (text text)');
$conn->exec("INSERT INTO test VALUES ('Lorem ipsum')");
$stream = $conn->openBlob('test', 'text', 1);
echo stream_get_contents($stream);
fclose($stream); // mandatory, otherwise the next line would fail
$conn->close();
?>The above example will output:
Lorem ipsumIncrementally writing a BLOB
<?php
$conn = new SQLite3(':memory:');
$conn->exec('CREATE TABLE test (text text)');
$conn->exec("INSERT INTO test VALUES (zeroblob(36))");
$stream = $conn->openBlob('test', 'text', 1, 'main', SQLITE3_OPEN_READWRITE);
for ($i = 0; $i < 3; $i++) {
fwrite($stream, "Lorem ipsum\n");
}
fclose($stream);
echo $conn->querySingle("SELECT text FROM test");
$conn->close();
?>The above example will output:
Lorem ipsum
Lorem ipsum
Lorem ipsum