Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '81fcb2a71a4ebb6cbae4268bd6615071cd037d687c7c238ff3eac2c7022a8b08' 
  AND token = 'lGazOPityx4173pHDi9xW541MHrzVDAc78JK3NjRd84=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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