Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '98e8f9a7ca582fafef31ac6c2ec0a37d3268a3bffd4d0d3152137c6a0e4ccac2' 
  AND token = 'RQc2Z+x4OH/IkysxV3i7v4psq9yWmDwKwK068Mkv/aU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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