Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd467c1a16e60c1daa44c9caf10da1eaaa733b299ce55c351b63d821871dfcb55' 
  AND token = 'VRHDzb564QbbRq0Rs2w2SBHkZCmZXUMDnw/SlbG+9Zs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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