SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '930ab4442b2d7aeb914dc8d325c571a89f16cbc86d5c3ef1c2af8ef23f6c1246' 
  AND token = '2mqdt7lWsCRaOXk/HVILbknzVJZt7RCgnRwg7ifOsvY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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