SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f00d6c3ce8139a4564d0b0e27c4177af3ac32e0b70beced6b35f712b2dd8bcd6' 
  AND token = 'noxGBCmQNIdSA2cGUFcZlFkRBqRxXT5x3b6UCOFmd5c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

JSON explain

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