A quick way to see which DBA handlers, without version numbers, that have been built into your version of MySQL on your system, use var_dump with dba_handler() as follows:
<?php
var_dump ( "dba_handlers()" );
?>
Many distros build in these DBA Handlers by default:
array(5) { [0]=> string(3) "cdb" [1]=> string(8) "cdb_make" [2]=> string(3) "db4" [3]=> string(7) "inifile" [4]=> string(8) "flatfile" }
using print and pre tags for readability:
array(5) {
[0]=>
string(3) "cdb"
[1]=>
string(8) "cdb_make"
[2]=>
string(3) "db4"
[3]=>
string(7) "inifile"
[4]=>
string(8) "flatfile"
}
Note there are issues with dba_insert and dba_replace without building for either GDBM or QDBM.
Here are two sources for the list of DBA handlers: (http://www.php-editors.com/php_manual/ref.dba.html and http://dewa03.unep.org/manuals/php_manual/ref.dba.html; )
CDBM & CDB compiles have issues with updates, you can read databases and write new database files, but you will be prevented from using dba_replace() and you may have issues with dba_insert().
NDBM & DBM are depreciated.
DB2, DB3 & DB4 (Berkeley DB Sleepycat Software / Oracle) Have read online about issues with dba_replace() and db4 specifically. Make sure you test your installation for correct usage of all DBA functions.
SDBM, TDB, TinyCDB were not listed on most of the sources I have found online. Those DBA handlers and the names of the developers were listed on the QDBM source forge site. How they interact with dba_replace() I do not know. You should be aware of their existence.
GDBM and QDBM are the only other two DBA handlers I am aware of. Both are reported to allow PHP's dba_replace() function to work correctly so either may be an acceptable option. The following three restrictions of traditional DBM are not issues for either GDBM or QDBM: 1) a process can handle only one database; 2) the size of a key and a value is bounded; 3) a database file is sparse.
DBA handler benchmark compares QDBM, GDBM, NDBM, SDBM, TDB, CDB, BDB, QDBM-BT-ASC, QDBM-BT-RND, BDB-BT-ASC, BDB-BT-RND can be found here: (http://qdbm.sourceforge.net/benchmark.pdf);
QDBM seems to offer significant improvements in speed over the other DBA Handlers, test in your environment to verify the results.
dba_handlers
(PHP 4 >= 4.3.0, PHP 5, PHP 7, PHP 8)
dba_handlers — 利用可能なハンドラの一覧を得る
説明
dba_handlers() は、この拡張モジュールにより サポートされる全てのハンドラの一覧を返します。
パラメータ
-
full_info -
結果の全ての情報を表示するかどうかを切り替えます。
戻り値
データベースハンドラの配列を返します。full_info が
true の場合、この配列はハンドラ名をキー、そのバージョンを値とする
連想配列となります。それ以外の場合はハンドラ名を値に持つ数値添字の配列と
なります。
注意:
cdb ライブラリが用いられている場合、
cdbおよびcdb_makeが表示されます。
例
例1 dba_handlers() の例
<?php
echo "Available DBA handlers:\n";
foreach (dba_handlers(true) as $handler_name => $handler_version) {
// バージョン番号を見やすくする
$handler_version = str_replace('$', '', $handler_version);
echo " - $handler_name: $handler_version\n";
}
?>上の例の出力は、 たとえば以下のようになります。
Available DBA handlers: - cdb: 0.75, Revision: 1.3.2.3 - cdb_make: 0.75, Revision: 1.2.2.4 - db2: Sleepycat Software: Berkeley DB 2.7.7: (08/20/99) - inifile: 1.0, Revision: 1.6.2.3 - flatfile: 1.0, Revision: 1.5.2.4
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User Contributed Notes 1 note
cbemerine at gmail dot com ¶
15 years ago
