diff --git a/include/db_filter.php b/include/db_filter.php
new file mode 100644
index 0000000..2ae001a
--- /dev/null
+++ b/include/db_filter.php
@@ -0,0 +1,191 @@
+<?php
+
+/**
+ * Classes for managing SQL filters (parts of SQL queries)
+ *
+ * Copyright 2008 BitSplash Software LLC
+ * Copyright 2008 Alexander N. Sørnes <alex@thehandofagony.com>
+ *
+*/
+
+define('FILTER_LIKE', 1);
+define('FILTER_EQUALS', 2);
+define('FILTER_GREATER_THAN', 3);
+define('FILTER_LESS_THAN', 4);
+define('FILTER_NOT_EQUALS', 5);
+define('FILTER_NOT_LIKE', 6);
+
+/* A filter as part of an SQL query, such as something = 'somevalue' */
+class Filter
+{
+    private $sColumn; // The table column the filter is for
+    private $iType; // The type of filter, like EQUALS, LIKE
+    private $sData; // What the column is to be compared to */
+
+    public function Filter($sColumn, $iType, $sData)
+    {
+        $this->sColumn = $sColumn;
+        $this->iType = $iType;
+        $this->sData = $sData;
+    }
+
+    public function getColumn()
+    {
+        return $this->sColumn;
+    }
+
+    public function setData($sData)
+    {
+        $this->sData = $sData;
+    }
+
+    public function getOperatorId()
+    {
+        return $this->iType;
+    }
+
+    public function getData()
+    {
+        return $this->sData;
+    }
+
+    public function getOperator()
+    {
+        switch($this->iType)
+        {
+            case FILTER_LIKE:
+                return 'LIKE';
+            case FILTER_EQUALS:
+                return '=';
+            case FILTER_LESS_THAN:
+                return '<';
+            case FILTER_GREATER_THAN:
+                return '>';
+            case FILTER_NOT_EQUALS:
+                return '!=';
+            case FILTER_NOT_LIKE:
+                return 'NOT LIKE';
+
+            default:
+                return 0; // error
+        }
+    }
+
+    public function getFilter()
+    {
+        $sOp = $this->getOperator();
+
+        return "{$this->sColumn} $sOp '{$this->sData}'";
+    }
+}
+
+/* Class handling tables where the user can filter contents */
+class FilterSet
+{
+    private $aFilters; // Array of filters for this table
+
+    public function FilterSet($sTableName = '')
+    {
+        $this->aFilters = array();
+
+        if($sTableName)
+            $this->loadTable($sTableName);
+    }
+
+    public function loadTable($sTableName)
+    {
+        $sQuery = "SELECT * FROM $sTableName";
+        $hResult = query_appdb($sQuery);
+
+        while($oRow = mysql_fetch_object($hResult))
+        {
+            $this->addFilterObject(new Filter($oRow->sColumn, $oRow->iType, $oRow->sData));
+        }
+    }
+
+    public function saveTable($sTableName)
+    {
+        $hResult = query_appdb("DROP TABLE IF EXISTS $sTableName");
+
+        $hResult = query_appdb("CREATE TABLE $sTableName (
+                                   sColumn VARCHAR(255) NOT NULL,
+                                   iType INT(3) NOT NULL,
+                                   sData VARCHAR(255) NOT NULL DEFAULT ''
+                                   )");
+
+        if(!$hResult)
+            return false;
+
+        $bSuccess = true;
+        foreach($this->aFilters as $oFilter)
+        {
+            $hResult = query_appdb("INSERT INTO $sTableName (sColumn,iType,sData)
+                                    VALUES('{$oFilter->getColumn()}','{$oFilter->getOperatorId()}','{$oFilter->getData()}')");
+            if(!$hResult)
+                $bSuccess = false;
+        }
+        return $bSuccess;
+    }
+
+    public function addFilterObject(Filter $oFilter)
+    {
+        $this->aFilters[] = $oFilter;
+    }
+
+    public function AddFilter($sColumn, $iType, $sData)
+    {
+        $this->aFilters[] = new Filter($sColumn, $iType, $sData);
+    }
+
+    public function getFilterCount()
+    {
+        return sizeof($this->aFilters);
+    }
+
+    public function getFilters()
+    {
+        return $this->aFilters;
+    }
+
+    public function getWhereClause()
+    {
+        $sFilter = '';
+        for($i = 0; $i < sizeof($this->aFilters); $i++)
+        {
+            $oFilter = $this->aFilters[$i];
+
+            $sFilter .= $oFilter->getFilter();
+
+            if($i < sizeof($this->aFilters) - 1)
+                $sFilter .= ' AND ';
+        }
+
+        return $sFilter;
+    }
+
+    function getQuery($sTable, $iLimit = 0)
+    {
+        $sWhere = $this->getFilterCount() ? 'WHERE '.$this->getWhereClause() : '';
+        $sQuery = "SELECT * FROM $sTable $sWhere";
+
+        $iLimit = mysql_real_escape_string($iLimit);
+
+        if($iLimit)
+            $sQuery .= " LIMIT 0,$iLimit";
+
+        return $sQuery;
+    }
+
+    function getMatchedItems($sTable, $iLimit = 0)
+    {
+        return query_appdb($this->getQuery($sTable, $iLimit));
+    }
+
+    function getMatchedItemsCount($sTable)
+    {
+        return mysql_num_rows($this->getMatchedItems($sTable));
+    }
+
+}
+
+?>
diff --git a/include/db_filter_ui.php b/include/db_filter_ui.php
new file mode 100644
index 0000000..71c90c9
--- /dev/null
+++ b/include/db_filter_ui.php
@@ -0,0 +1,251 @@
+<?php
+
+/**
+ * User interface for the SQL filter classes
+ *
+ * Copyright 2008 BitSplash Software LLC
+ * Copyright 2008 Alexander N. Sørnes <alex@thehandofagony.com>
+ *
+*/
+
+require_once('db_filter.php');
+
+/* Info describing an available filter: what column it applies to,
+    and what comparison options are available */
+class FilterInfo
+{
+    private $sColumn;
+    private $sDisplayName;
+    private $aTypes; // Available filters for this column
+
+    public function FilterInfo($sColumn, $sDisplayName, $aTypes)
+    {
+        $this->sColumn = $sColumn;
+        $this->sDisplayName = $sDisplayName;
+        $this->aTypes = $aTypes;
+    }
+
+    public function getColumn()
+    {
+        return $this->sColumn;
+    }
+
+    public function getDisplayName()
+    {
+        return $this->sDisplayName;
+    }
+
+    public function getTypes()
+    {
+        return $this->aTypes;
+    }
+
+    public static function getOpName($iOpId)
+    {
+        switch($iOpId)
+        {
+            case FILTER_EQUALS:
+                return 'equal to';
+            case FILTER_LIKE:
+                return 'like';
+            case FILTER_NOT_LIKE:
+                return 'not like';
+            case FILTER_NOT_EQUALS:
+                return 'not equal to';
+            case FILTER_LESS_THAN:
+                return 'less than';
+            case FILTER_GREATER_THAN:
+                return 'greater than';
+        }
+    }
+}
+
+/* Class handling tables where the user can filter contents */
+class FilterInterface
+{
+    private $aFilterInfo;
+    private $oFilterSet;
+
+    public function FilterInterface($sTableName = '')
+    {
+        $this->aFilterInfo = array();
+        $this->oFilterSet = new FilterSet(mysql_real_escape_string($sTableName));
+    }
+
+    public function AddFilterObject(Filter $oFilter)
+    {
+        $this->oFilterSet->AddFilterObject($oFilter);
+    }
+
+    public function setFilterSet(FilterSet $oSet)
+    {
+        $this->oFilterSet = $oSet;
+    }
+
+    /* Convenience function to add a filter option */
+    public function AddFilterInfo($sColumn, $sDisplayName, $aTypes)
+    {
+        $this->aFilterInfo[$sColumn] = new FilterInfo($sColumn, $sDisplayName, $aTypes);
+    }
+
+    public function getItemEditor($iId, Filter $oFilter)
+    {
+        $sColumn = $oFilter->getColumn();
+        $oColumn = $this->aFilterInfo[$sColumn];
+
+        $sId = ($iId == -1) ? '' : $iId;
+        $shEditor = $oColumn->getDisplayName();
+
+        $shEditor .= " <select name='i{$sColumn}Op$sId'>";
+
+        if($iId == -1)
+        {
+            $sText = 'select';
+            $sSel = " selected='selected'";
+        } else
+        {
+            $sSel = '';
+            $sText = 'remove';
+        }
+
+        $shEditor .= "<option value='0'$sSel>-- $sText --</option>";
+
+        foreach($oColumn->getTypes() as $iType)
+        {
+            if($oFilter->getOperatorId() == $iType)
+                $sSel = " selected='selected'";
+            else
+                $sSel = '';
+            $shEditor .= "<option value='$iType'$sSel>".$oColumn->getOpName($iType).'</option><br />';
+        }
+
+        $shEditor .= '</select> ';
+
+        $shEditor .= "<input type='text' value=\"{$oFilter->getData()}\" name='s{$sColumn}Data$sId' size='30' />";
+
+        return $shEditor;
+    }
+
+    public function getEditor()
+    {
+        $shEditor = '';
+        $aCounts = array();
+
+        $shEditor .= 'Add new filter<br />';
+        foreach($this->aFilterInfo as $oOption)
+        {
+            $oDummyFilter = new Filter($oOption->getColumn(), 0, '');
+            $shEditor .= $this->getItemEditor(-1, $oDummyFilter);
+            $shEditor .= '<br />';
+        }
+
+        if(sizeof($this->oFilterSet->getFilters()))
+             $shEditor .= '<br />Active filters<br />';
+        foreach($this->oFilterSet->getFilters() as $oFilter)
+        {
+            $sColumn = $oFilter->getColumn();
+
+            if(!array_key_exists($sColumn, $aCounts))
+                $aCounts[$sColumn] = 0;
+
+            $shEditor .= $this->getItemEditor($aCounts[$sColumn], $oFilter);
+            $shEditor .= '<br />';
+
+            $aCounts[$sColumn]++;
+        }
+
+        return $shEditor;
+    }
+
+    public function getFilterInfo()
+    {
+        return $this->aFilterInfo;
+    }
+
+    /* Reads all input related to filters for the given table column */
+    public function readInputForColumn($aClean, FilterInfo $oOption)
+    {
+        $aReturn = array();
+
+        for($i = 0; array_key_exists('i'.$oOption->getColumn()."Op$i", $aClean); $i++)
+        {
+            $sData = mysql_real_escape_string($aClean["s{$oOption->getColumn()}Data$i"]);
+            $iOp = $aClean["i{$oOption->getColumn()}Op$i"];
+
+            if(!$iOp)
+                continue;
+
+            $oFilter = new Filter($oOption->getColumn(), $iOp, $sData);
+            $aReturn[] = $oFilter;
+        }
+
+        if(array_key_exists('i'.$oOption->getColumn()."Op", $aClean))
+        {
+            $i = sizeof($aReturn);
+            $sData = $aClean["s{$oOption->getColumn()}Data"];
+            $iOp = $aClean["i{$oOption->getColumn()}Op"];
+
+            if($iOp)
+            {
+                $oFilter = new Filter($oOption->getColumn(), $iOp, $sData);
+                $aReturn[] = $oFilter;
+            }
+        }
+
+        return $aReturn;
+    }
+
+    /* Reads an input array get enabled filters from form data.
+       The given TableFilterSet defines available options */
+    public function readInput($aClean)
+    {
+        foreach($this->getFilterInfo() as $oOption)
+        {
+            foreach($this->readInputForColumn($aClean, $oOption) as $oNewFilter)
+                $this->AddFilterObject($oNewFilter);
+        }
+    }
+
+    public function loadTable($sTableName)
+    {
+        $this->oFilterSet->loadTable(mysql_real_escape_string($sTableName));
+    }
+
+    public function saveTable($sTableName)
+    {
+        $this->oFilterSet->saveTable(mysql_real_escape_string($sTableName));
+    }
+
+    public function getFilterCount()
+    {
+        return $this->oFilterSet->getFilterCount();
+    }
+
+    public function getTable($sTable, $iLimit = 0)
+    {
+        $hResult = $this->oFilterSet->getMatchedItems($sTable, $iLimit);
+
+        if(!$hResult)
+            return;
+
+        echo 'Selected '.$this->oFilterSet->getMatchedItemsCount($sTable).' rows<br><br>';
+
+        $oTable = new Table();
+
+        while($aRow = mysql_fetch_row($hResult))
+        {
+            $oRow = new TableRow();
+
+            foreach($aRow as $sCell)
+            {
+                $oRow->AddTextCell($sCell);
+            }
+
+            $oTable->AddRow($oRow);
+        }
+
+        return $oTable->getString();
+    }
+}
+
+?>