SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2ce9bc4a252bf9de6b043f083988793fbecbd1de7076c0ba4bb428584aeabd25' 
  AND token = 'YIIKeyDwCDhwIl6/QKkgqN1juah+TffCG3b75qnXAOI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}