php - 如何对我的代码进行一次查询

Question

如何对我的代码进行一次查询

$sql = "SELECT id FROM countries WHERE country_code = LEFT($number,3)"; 
$sql = "SELECT id FROM countries WHERE country_code = LEFT($number,2)"; 
$sql = "SELECT id FROM countries WHERE country_code = LEFT($number,1)"; 
$sql = "SELECT id FROM countries WHERE country_code = 0";

Answer 1

$sql = "SELECT id
FROM countries
WHERE country_code = LEFT($number,3)
  OR country_code = LEFT($number,2)
  OR country_code = LEFT($number,1)
  OR country_code = 0";