SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1e804ae566d257002328c97aa4919d8bda29234dde986e14278d72ad1b287a23' 
  AND token = 'Uomy/2NtoNrxlhCKubKcHuuZd8gVkoGPA/p23sA4XIM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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