php8.5
Home/ Manual/ reference / dba/ Basic usage

Basic usage

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

Examples

Basic usage

DBA example

php
<?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.

Traversing a database

php
<?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);
}

?>

Source: reference/dba/examples.xml · from the official PHP manual (php/doc-en)