SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '22b98a293e93bbd8014c73655bcb279817fa89d9aeb9dcb9f019a3b5d2bd6e78' 
  AND token = '81IRukB83Ccez/VsXFYACj/JxwHyNMhJRFDpKqqUI5E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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