SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b96b96a5060bfe71757336d59868e34d3fbd1c45ce4b7cf56abe1a883edd68d1' 
  AND token = 'WjKx2yvP3wPKnT7Wl9HLEgibZZYsPrYREhCGHjGedrs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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