SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'e1e55a316caa69d20f629a7ccd3807f84902456294e69bfe6c6f38693765fe79' 
  AND token = 'YZrGEwrgkvtgV/Na6Youvvz6bgdINDi6YQURL1vwn6E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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