SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ca935643be617300782725f9ea2df58312d8999d84a084e13fc705be8b9277e8' 
  AND token = 'lN4e1r32qctal5UDUsNEClMp6mK+xbtNOvE6LtkIHOQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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