SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e1c0d114c7c69733e33bdf53ca198e08b8a56225ca8bdf624030f3adb03525a0' 
  AND token = 'u2ZxL0FJpVhBpwCG968UIs74gn948X1iY3ORoKxt4mU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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