SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '097eb2ca8630c37f63ba791fea9bf7f2f3555184a7536d55a47b7fe77cff241b' 
  AND token = 'HeDmzziGgd3IEzcmYtvYfaiYo4uMxsNmkSW8oZ0LUOo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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