This document introduces a dbm-style abstraction layer for storing data in PHP. It allows caching objects, strings, integers or arrays by key-value in databases like Berkeley DB, Quick Database Manager or GNU Database Manager. The layer wraps the dba_* functions and can be used to store, retrieve, delete and get metadata for cached items. It also provides options for cleaning cached data by removing all entries, expired entries or flushing the entire storage file.

1. Store data into dbm-style abstraction layer

2. Introduction
 uses the database (dbm-style)
abstraction layer
 store/ cache your objects, strings,
integers or arrays
 even instances of SimpleXMLElement
 it depends on the free space of your disk
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3. Repository
 GitHub gjerokrsteski/php-dba-cache
 ZF-11073 Zend_Cache_Backend_Dba
 ZF2-139 ZendCacheStorageAdapterDba
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4. How it works
 dbm-style abstraction layer
 wraps dba_* functions
 Installation
 ./configure
--enable-dba=shared
--with-[handler]
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5. DBA handlers
 cdb Tiny Constant Database = r
 cdb_make Tiny Constant Database = w
 db4 Oracle Berkeley DB 4 = rw
 qdbm Quick Database Manager = rw
 gdbm GNU Database Manager = rw
 inifile Ini File = rw
 flatfile default = rw
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6. Cache options
 open database
 insert, replace, get, delete record by key
 return metadata = expire + mtime
 get all keys
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7. Sweep options
 is optional
 clean all entries
 clean expired entries
 flush the cache/storage file
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8. DB 4 with persistent connection
$cache = new Cache(
'/your/path/to/cache-file.db4', 'db4'
);
$yorObject = new YourObjectYouWantToPutInCache();
$yourObjectIdentifier = 'key:you:want';
// Check if your object is in the cache.
// You also can ignore it, and let the CacheDba do it for you.
if (false == $cache->has($yourObjectIdentifier)) {
$cache->delete($yourObjectIdentifier);
}
$cache->put($yourObjectIdentifier, $yorObject);
// Than somewhere at your project.
$cache->get($yourObjectIdentifier);
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9. Sweep in action
// For the garbage collection you can
// create for example an cron-job starting once a day
// or please use the DBA-Cache-Monitor GUI.
$sweep = new Sweep($cache);
// clean all entries
$sweep->all();
// or clean old entries – from now
$sweep->old();
// or flush the whole storage!
$sweep->flush();
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10. Cache Monitor
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11. Have fun with it…
Gjero Krsteski
Programmer, Consultant, Trainer
Homepage: krsteski.de
E-Mail: gjero@krsteski.de
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