Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4801c743a0522403e811efde01ad246f3f542f6bb78d40403e5d7cbe8cb0396b' 
  AND token = '3MmZ20ONKjOhfltNkk/03wTaqkkYWzLV0r+atjELFVc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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