SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fd21744a07f13d6c983171f41dd5d0b30fe8e3355847cd50cc221b52c711d246' 
  AND token = 'TieCPy+4e/sjZCgcNxtcpAveLEnCjcZq2cMrZP5frcI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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