adding counting methods

src/DSOFactoryInterface.php

@@ -17,4 +17,5 @@ interface DSOFactoryInterface
 
     public function search() : Search;
     public function executeSearch(Search $search, array $params = array(), $deleted = false) : array;
+    public function executeCount(Search $search, array $params = array(), $deleted = false) : ?int;
 }

src/Drivers/AbstractDriver.php

@@ -85,6 +85,18 @@ abstract class AbstractDriver implements DSODriverInterface
         ]);
     }
 
+    public function count(string $table, Search $search, array $params)
+    {
+        $s = $this->getStatement(
+            'count',
+            ['table'=>$table,'search'=>$search]
+        );
+        if (!$s->execute($params)) {
+            return null;
+        }
+        return intval($s->fetchAll(\PDO::FETCH_COLUMN)[0]);
+    }
+
     public function select(string $table, Search $search, array $params)
     {
         $s = $this->getStatement(

src/Drivers/MySQLDriver.php

@@ -45,6 +45,20 @@ class MySQLDriver extends AbstractDriver
         return implode(PHP_EOL, $out).';';
     }
 
+    protected function sql_count($args)
+    {
+        //extract query parts from Search and expand paths
+        $where = $this->expandPaths($args['search']->where());
+        //select from
+        $out = ["SELECT count(dso_id) FROM `{$args['table']}`"];
+        //where statement
+        if ($where !== null) {
+            $out[] = "WHERE ".$where;
+        }
+        //return
+        return implode(PHP_EOL, $out).';';
+    }
+
     protected function sql_ddl($args=array())
     {
         $out = [];

src/Factory.php

@@ -181,6 +181,18 @@ class Factory implements DSOFactoryInterface
         return $arr;
     }
 
+    public function executeCount(Search $search, array $params = array(), $deleted = false) : ?int
+    {
+        //add deletion clause and expand column names
+        $search = $this->preprocessSearch($search, $deleted);
+        //run select
+        return $this->driver->count(
+            $this->table,
+            $search,
+            $params
+        );
+    }
+
     public function executeSearch(Search $search, array $params = array(), $deleted = false) : array
     {
         //add deletion clause and expand column names

src/LegacyDrivers/AbstractLegacyDriver.php

@@ -34,6 +34,20 @@ class AbstractLegacyDriver extends AbstractDriver
         return $results;
     }
 
+    protected function sql_count($args)
+    {
+        //extract query parts from Search and expand paths
+        $where = $this->expandPaths($args['search']->where());
+        //select from
+        $out = ["SELECT count(dso_id) FROM `{$args['table']}`"];
+        //where statement
+        if ($where !== null) {
+            $out[] = "WHERE ".$where;
+        }
+        //return
+        return implode(PHP_EOL, $out).';';
+    }
+
     protected function sql_select($args)
     {
         //extract query parts from Search and expand paths

src/Search.php

@@ -18,6 +18,11 @@ class Search implements \Serializable
         $this->factory = $factory;
     }
 
+    public function count(array $params = array(), $deleted = false)
+    {
+        return $this->factory->executeCount($this, $params, $deleted);
+    }
+
     public function execute(array $params = array(), $deleted = false)
     {
         return $this->factory->executeSearch($this, $params, $deleted);