SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '5f1c4b42755116f7c23432059b473a985383a2fdbc577f9bc0c5bb17834a9668' 
  AND token = '9b7v18M3dqlgS4FmbhO68S0f7rKX6GPC75pBjMyErzQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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