2

我正在condeigniter（新手）的一个项目上工作。我的项目包括使用不同过滤器（如类别、子类别、关键字、最低-最高价格等）的产品列表。我已经在自定义 php 中完成了数百次，在这里我为子句$where中的所有条件设置了变量。where例如

$where = '';
if($category != '')
{
  $where .= " category = '$category'";
}

现在在 codeigniter 中我有多个参数，我可以在我的controllerthroughuri segment和 callmodel函数中获取它们，并在那里传递所有参数run mysql query。问题是我正在检查每个参数是否为空或已设置并相应地运行多个查询。例如。

if($category != '' && $subCategory != '')
{
  //whole query here
}
else  if($category == '' && $subCategory != '')
{
  //whole query here
}

//and so on

我需要的是任何优化方式，因为我有连接（多个参数）。

我的示例条件和查询

if($subCat == '' && $vendor == '')
    {
        $cat = str_replace("-"," ",str_replace("-and-"," & ",$cat));
        $this->db->select('listings.* ');
        $this->db->from('listings');
        $this->db->join('categories','categories.id = listings.category');
        $this->db->where('categories.name',$cat);
        $this->db->limit($perpage,$page);
        $query = $this->db->get();
        return $query->result();
    }
    else if($subCat == '' && $vendor != '')
    {
        $cat = str_replace("-"," ",str_replace("-and-"," & ",$cat));
        $this->db->select('listings.* ');
        $this->db->from('listings');
        $this->db->join('categories','categories.id = listings.category');
        $this->db->join('vendors','vendors.id = listings.programme');
        $this->db->where('categories.name',$cat);
        $this->db->where('vendors.name',$vendor);
        $this->db->limit($perpage,$page);
        $query = $this->db->get();
        return $query->result();
    }
    else if($subCat != '' && $vendor == '')
    {
        $cat = str_replace("-"," ",str_replace("-and-"," & ",$cat));
        $this->db->select('listings.* ');
        $this->db->from('listings');
        $this->db->join('categories','categories.id = listings.category');
        $this->db->join('subcategories','subcategories.id = listings.subcategory');
        $this->db->where('categories.name',$cat);
        $this->db->where('subcategories.name',$subCat);
        $this->db->limit($perpage,$page);
        $query = $this->db->get();
        return $query->result();
    }
    else
    {
        $cat = str_replace("-"," ",str_replace("-and-"," & ",$cat));
        $subCat = str_replace("-"," ",str_replace("-and-"," & ",$subCat));
        $vendor = str_replace("-"," ",str_replace("-and-"," & ",$vendor));

        $this->db->select('listings.* ');
        $this->db->from('listings');
        $this->db->join('categories','categories.id = listings.category');
        $this->db->join('subcategories','subcategories.id = listings.subcategory');
        $this->db->join('vendors','vendors.id = listings.programme');
        $this->db->where('categories.name',$cat);
        $this->db->where('subcategories.name',$subCat);
        $this->db->where('vendors.name',$vendor);
        $this->db->limit($perpage,$page);
        $query = $this->db->get();  
        return $query->result();
    }
4

2 回答 2

2

您只需要编写一次查询，而不是每次都需要编写查询。例如，您可能有多种情况，如您所描述的。例如，这是我所做的事情：

$this->db->select('resource.id,city.name as city_name,city.provinceID,resource.Rate, skills.name')->from('resource')
->join('city','resource.cityID = city.id')
->join('resourceToSkillsMap','resource.id = resourceToSkillsMap.resourceID')
->join('skills','skills.id =  resourceToSkillsMap.skillsID');

if($category != '' && $subCategory != '') #condition
{
    $this->db->where('condition');
}
else  if($category == '' && $subCategory != '') #condition
{
    $this->db->where('condition');
}

$rs = $this->db->group_by('resource.id')
->limit($limit,$offset)
->get();

查看查询是如何编写only once的，但where condition在if else. 所以你的查询将以这种方式建立。执行查询后只是echo $this->db->last_query();为了回显查询并根据需要进行调整。

于 2013-09-17T07:10:18.393 回答
1

在您的助手中，您可以$where array()像这样构建

$where = array();
if($category != '')
{
   $where['category'] = $category;
} else {
   $where['someotherkey'] = 'someothervalue';
}

在您的控制器中，您只需在调用模型时传递$where数组。

$this->foo_model->foo_method($where);

在模型中你可以做这样的事情

$this->db->where($where);

编辑

if($category != '')
{
   //Along with your $this->db->where()
   $this->db->join('table1','condition1');
} else {
   //Along with your $this->db->where()
   $this->db->join('table2','condition2');
}

收拾东西

$cat = str_replace("-"," ",str_replace("-and-"," & ",$cat));
$this->db->select('listings.* ');
$this->db->from('listings');
$this->db->join('categories','categories.id = listings.category');  
$this->db->where('categories.name',$cat);

if($vendor != '')      {
  $this->db->join('vendors','vendors.id = listings.programme');
  $this->db->where('vendors.name',$vendor);
}
if($subCat != ''){
  $subCat = str_replace("-"," ",str_replace("-and-"," & ",$subCat));
  $this->db->join('subcategories','subcategories.id = listings.subcategory');
  $this->db->where('subcategories.name',$subCat);
}    

$this->db->limit($perpage,$page);
$query = $this->db->get();
return $query->result();
于 2013-09-17T07:05:10.610 回答