Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a312c573410036497f3cfce1b7482a6838b2f5d6b3499c7c6c0c589eab3a6271' 
  AND token = 's3YZ47Gx/rM9Uy9CmKzxyyMk2m/YKlmGK1bTIYTSQfU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00052

JSON explain

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