1These functions build the foundation for accessing Berkeley DB style 2databases. 3 4This is a general abstraction layer for several file-based databases. As 5such, functionality is limited to a common subset of features supported 6by modern databases such as Sleepycat Software's DB2. (This is not to be 7confused with IBM's DB2 software, which is supported through the ODBC 8functions.) 9 10This extensions allows to work with the following databases: 11dbm DBM is the oldest (original) type of Berkeley DB style databases. 12 You should avoid it, if possible. We do not support the 13 compatibility functions built into DB2 and gdbm, because they are 14 only compatible on the source code level, but cannot handle the 15 original dbm format. 16ndbm NDBM is a newer type and more flexible than dbm. It still has 17 most of the arbitrary limits of dbm (therefore it is deprecated). 18gdbm GDBM is the GNU database manager. 19db2 DB2 is Sleepycat Software's DB2. It's described as "a programmatic 20 toolkit that provides high-performance built-in database support 21 for both standalone and client/server applications. 22db3 DB3 is Sleepycat Software's DB3. 23db4 DB4 is Sleepycat Software's DB4. This is available since PHP 5.0. 24cdb CDB is "a fast, reliable, lightweight package for creating and 25 reading constant databases." It is from the author of qmail and 26 can be found at http://cr.yp.to/cdb.html. Since it is constant, 27 we support only reading operations. And since PHP 4.3.0 we support 28 writing (not updating) through the internal cdb library. 29cdb_make Since PHP 4.3.0 we support creation (not updating) of cdb files 30 when the bundled cdb library is used. 31flatfile This is available since PHP 4.3.0 for compatibility with the 32 deprecated dbm extension only and should be avoided. However you 33 may use this where files were created in this format. That happens 34 when configure could not find any external library. 35inifile This is available since PHP 4.3.3 to be able to modify php.ini 36 files from within PHP scripts. When working with ini files you 37 can pass arrays of the form array(0=>group,1=>value_name) or 38 strings of the form "[group]value_name" where group is optional. 39 As the functions dba_firstkey() and dba_nextkey() return string 40 representations of the key there is a new function dba_key_split() 41 available since PHP 5 which allows to convert the string keys into 42 array keys without losing FALSE. 43qdbm This is available since PHP 5.0.0. The qdbm library can be loaded 44 from http://qdbm.sourceforge.net. 45 46 47After configuring and compiling PHP you must execute the following test 48from commandline: 49 php run-tests.php ext/dba. 50This shows whether your combination of handlers works. Most problematic 51are dbm and ndbm which conflict with many installations. The reason for 52this is that on several systems these libraries are part of more than one 53other library. The configuration test only prevents you from configuring 54malfaunctioning single handlers but not combinations. 55
