SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e49e750361c4ef4130663c430cc2ec723d6d73d17dc8474351c10a74fa97935b' 
  AND token = 'oCkTaCegCvB1Kl2aqJ6x7HlikaxqF6cVogkosGZW5dY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00052

JSON explain

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