SELECT 
  1 
FROM 
  vi_lock_keys 
WHERE 
  key_id = '9491cef70ae3dc80a7823bd8e4b9f759fec13b173a2f6c7c99b84d3ad0cd2a46' 
  AND token = '2nPVVITiXKMki8JRz2ZUnzmFOL/IiNK0RG+w0uPHDOM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00008

JSON explain

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