Magento 1.9 Admin Grid – Not Displaying and Collection Returning False Value

I am creating a small admin module. When i did var_dump($collection) in my Grid.php file i get false value. Also i am not able to see the grid too.

Moreover, i am able to see my header text and button ie: Add Banner.

My module files are as below.

config.xml

<?xml version="1.0"?>
<config>
    <modules>
        <Greeting_Greetingslider>
            <version>0.1.0</version>
        </Greeting_Greetingslider>
    </modules>
    <frontend>
        <routers>
            <greetingslider>
                <use>standard</use>
                <args>
                    <module>Greeting_Greetingslider</module>
                    <frontName>greetingslider</frontName>
                </args>
            </greetingslider>
        </routers>
    </frontend>
    <admin>
        <routers>
            <greetingslider>
                <use>admin</use>
                <args>
                    <module>Greeting_Greetingslider</module>
                    <frontName>greetingslider</frontName>
                </args>
            </greetingslider>
        </routers>
    </admin>
    <global>
        <helpers>
            <greetingslider>
                <class>Greeting_Greetingslider_Helper</class>
            </greetingslider>
        </helpers>
        <blocks>
            <greetingslider>
                <class>Greeting_Greetingslider_Block</class>
            </greetingslider>
        </blocks>
        <models>
            <greetingslider>
                <class>Greeting_Greetingslider_Model</class>
                <resourceModel>slider_mysql4</resourceModel>
            </greetingslider>
            <slider_mysql4>
                <class>Greeting_Greetingslider_Model_Mysql4</class>
                <entities>
                    <greetingslider>
                        <table>greetingslider</table>
                    </greetingslider>
                </entities>
            </slider_mysql4>
        </models>
        <resources>
            <greetingslider_setup>
                <setup>
                    <module>Greeting_Greetingslider</module>
                </setup>
                <connection>
                    <use>core_setup</use>
                </connection>
            </greetingslider_setup>
            <greetingslider_write>
                <connection>
                    <use>core_write</use>
                </connection>
            </greetingslider_write>
            <greetingslider_read>
                <connection>
                    <use>core_read</use>
                </connection>
            </greetingslider_read>
        </resources>
    </global>
    <adminhtml>
        <menu>
            <greetingslider module="greetingslider">
                <title>Greeting Slider</title>
                <sort_order>100</sort_order>
                <children>
                    <items module="greetingslider">
                        <title>Manage Banners</title>
                        <action>greetingslider/adminhtml_greetingslider</action>
                    </items>
                </children>
            </greetingslider>
        </menu>
        <acl>
            <resources>
                <all>
                    <title>Allow Everything</title>
                </all>
                <admin>
                    <children>
                        <greeting_greetingslider>
                            <title>Greeting Slider</title>
                            <sort_order>10</sort_order>
                        </greeting_greetingslider>
                    </children>
                </admin>
            </resources>
        </acl>
        <layout>
            <updates>
                <greetingslider>
                    <file>greetingslider.xml</file>
                </greetingslider>
            </updates>
        </layout>
    </adminhtml>
</config>

app/code/local/Greeting/Greetingslider/Model/Greetingslider.php

<?php
class Greeting_Greetingslider_Model_Greetingslider extends Mage_Core_Model_Abstract{
    public function _construct(){
        parent::_construct();
        $this->_init('greetingslider/greetingslider');
    }
}

app/code/local/Greeting/Greetingslider/Model/Mysql4/Greetingslider.php

<?php class Greeting_Greetingslider_Model_Mysql4_Greetingslider extends Mage_Core_Model_Mysql4_Abstract{
    public function _construct(){
        $this->_init('greetingslider/greetingslider','slide_id');
    } }

app/code/local/Greeting/Greetingslider/Model/Mysql4/Greetingslider/Collection.php

<?php
class Greeting_Greetingslider_Model_Mysql4_Greetingslider_Collection extends Mage_Core_Model_Resource_Db_Collection_Abstract{
    public function _construct(){
        $this->_init('greetingslider/greetingslider');
    }
}

app/code/local/Greeting/Greetingslider/Block/Adminhtml/Greetingslider.php

<?php
class Greeting_Greetingslider_Block_Adminhtml_Greetingslider extends Mage_Adminhtml_Block_Widget_Grid_Container{
    public function __construct(){
        $this->_controller = 'adminhtml_greetingslider';
        $this->_blockGroup = 'greetingslider';
        $this->_headerText = Mage::helper('greetingslider')->__('Banner Manager');
        $this->_addButtonLabel = Mage::helper('greetingslider')->__('Add Banner');
        parent::__construct(); 
    }
}

app/code/local/Greeting/Greetingslider/Block/Adminhtml/Greetingslider/Grid.php

<?php
class Greeting_Greetingslider_Block_Adminhtml_Greetingslider_Grid extends Mage_Adminhtml_Block_Widget_Grid{
    public function __construct(){
        parent::__construct();
        $this->setId('greetingslider_grid');
        $this->setDefaultSort('slide_id');
        $this->setDefaultDir('ASC');
        $this->setSaveParametersInSession(true);
    }
    protected function _prepareCollection(){
        $collection = Mage::getModel('greetingslider/greetingslider')->getCollection();
        var_dump($collection);
        $this->setCollection($collection);
        return parent::_prepareCollection();
    } 
    protected function _prepareColumns(){
         $this->addColumn('slide_id', array(
            'header' => Mage::helper('greetingslider')->__('ID'),
            'align' => 'right',
            'width' => '10px',
            'index' => 'slide_id',
        ));
        return parent::_prepareColumns();
    }
    public function getRowUrl($row) {
        return $this->getUrl('*/*/edit', array('id' => $row->getId()));
    } 
}

app/code/local/Greeting/Greetingslider/controllers/Adminhtml/GreetinsliderController.php

<?php 
class Greeting_Greetingslider_Adminhtml_GreetingsliderController extends Mage_Adminhtml_Controller_action {
    protected function _initAction(){
        $this->loadLayout()->_setActiveMenu('greetingslider/greetingslider')->_addBreadcrumb(
            Mage::helper('adminhtml')->__('Banner Slider'),
            Mage::helper('adminhtml')->__('Slide Manager')
        );
        return $this;
    }
    public function indexAction(){
        $this->_initAction()->renderLayout();
    }
}

I am not able to figure out where is the mistake. Also i have a table in database named greetingslider