SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bd29d2cc3092302a30719825edfcd9518a809fda5bd9623b1004653c26e58880' 
  AND token = '90WC0ROyt57ixfCmmAERQ18S/OaSYM8Si94zanUoVpQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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