Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '98687e3251b24dd02fe0da733dd473ebec87f42721bb318caad3cadeb8b514f1' 
  AND token = '51YMbIpzfEABEb+dEdiRLPe2ek4nVL+mpCB/Ph2SbCE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}