SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '762186a0dd4a55b5fb9c065f8ea985acba677d3a2067dc50f3ca976970636011' 
  AND token = 'JaRHpEtTO5pWnkxuYDlSYkFpAf9YM7H2TRBG2lrUcyE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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