扩展MySQL的声明

Question

是CI中或PHP能够扩展MySQL的声明。例如。如果我有$query1。我可以在另一个$this->db->query()实例添加到$query1：

$query1 = this->db->query("SELECT * FROM users WHERE a = b"); 

$query1(or 2) = $this->db->query("AND b = c"); 

Answer 1

把你的陈述在var和扩展字符串，如果需要：

$strStatement = "SELECT * FROM users WHERE a = b"; 

if (/* whatever */) 
{ 
    $strStatement .= " AND b = c"; 
} 

$objResult = $this->db->query($strStatement); 

Answer 2

check out the documentation。这是可以实现（作为一个例子）与：

$this->db->where('a', 'b'); 
if($condition) 
{ 
    $this->db->where('b', 'c'); 
} 
$this->db->get('users'); //implicitly runs a "SELECT *"