SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7af988feb4911b9a6183af5e46f6e10a75f5ee0c4f386c956aee24d9fe92d969' 
  AND token = 'D3xxnsT/nnCk2j3E/dFE1Yysgebi4x2ZP5IKKzEWDHw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}