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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dfa878277e8b90d135c0ced03fd8f8a05aaac7256c8c8ce4fd3ae734aeb5649f' 
  AND token = 'al6t6ZrWDEbHqQeQ5iPe83HkN1ZtvfadlgsGsGiZmGM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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