SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7806576154f9481b165eea6ba403cc99e9669c577c19788c22cde91b0fdb8202' 
  AND token = 'pWNtdOWT7v3sxGpDkNRLNfdbyiOuK3RYc8ylsJoKNfE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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