SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'f02ac87133959f31abcdca64e8f50eb06ed63679b6de33ccd439914390edf596' 
  AND token = 'fdLSIJ4aoJCR5lBRI2sv9z7binYgOvosY3hx/+5lYzQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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