Php/docs/dba.example

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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);}?>