SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '212076ec7686aa6bb96ccfb08959bb56d1f1914b1bb9baca94d136b081ba6ef3' 
  AND token = 'evTAJ4msHkSFXXBwndd19tXh99QpjwAsdS8IA4Lbxcs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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