SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f4766dd95318a9bea34860c49ef2224cbbdc1099bb0b3879d9675f9781353e47' 
  AND token = 'wJETpHsvlMsMnnpCDqaSr3IVUU4XouB7ohK8by+JoGs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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