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ext/spl/README

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+<pre>
+This is an extension that aims to implement some efficient data access 
+interfaces and classes.
+
+SPL allows to hook into foreach. Doing so you can do something like
+this:
+
+	$obj = new whatever();
+	foreach($obj as $key => $value) { ... }
+
+This is meant to be used for database access. For example you could
+grab my patch to sqlite (<a href="http://marcus-boerger.de/php/ext/sqlite/">http://marcus-boerger.de/php/ext/sqlite/</a>) and
+look at the oo tests:
+
+	$db = new sqlite($filename);
+	foreach($db->query("SELECT....") as $row) { ... }
+
+SQLite offers four access strategies:
+1) sqlite_query + sqlite_fetch_array
+2) sqlite_unbuffered_query + sqlite_fetch_array
+3) sqlite_query + iterators (sqlite_current)
+4) sqlite_unbuffered_query + iterators (sqlite_current)
+
+1) and 3) do "over eager evaluating" since they fetch all rows directly.
+
+2) does "eager evaluating". It always fetches the next row but doesn't 
+keep the current row, so that it must be stored elsewhere if it must be 
+accessed more then once. For instance this happens when you need to access 
+columns separately.
+
+4) does "eager evaluating". But in contrast to 2) it keeps the current row
+hence its name.
+
+There is no efficient way for "lazy or just in time evaluating" so 4) should 
+be the best case. And 4) also enables the foreach trick.
+
+To implement 3) and 4) with other db extensions ask me and wait for LT to pass.
+
+</pre>