PHP Manual: Basic usage

Basic usage

Example #1 DBA example

<?php

$id = dba_open("/tmp/test.db", "n", "db2");

if (!$id) {
    echo "dba_open failed\n";
    exit;
}

dba_replace("key", "This is an example!", $id);

if (dba_exists("key", $id)) {
    echo dba_fetch("key", $id);
    dba_delete("key", $id);
}

dba_close($id);
?>

DBA is binary safe and does not have any arbitrary limits. However, it inherits all limits set by the underlying database implementation.

All file-based databases must provide a way of setting the file mode of a new created database, if that is possible at all. The file mode is commonly passed as the fourth argument to dba_open() or dba_popen().

You can access all entries of a database in a linear way by using the dba_firstkey() and dba_nextkey() functions. You may not change the database while traversing it.

Example #2 Traversing a database

<?php

// ...open database...

$key = dba_firstkey($id);

while ($key !== false) {
    if (true) {          // remember the key to perform some action later
        $handle_later[] = $key;
    }
    $key = dba_nextkey($id);
}

foreach ($handle_later as $val) {
    dba_delete($val, $id);
}

?>