SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dd007f55390960b135938ede1c240b677a2120b11f2f7dce745a139c215c0a38' 
  AND token = 'h86mV6bezBLIXoWBt4FDraWRTuLAHSOjuAqcl/tAYqc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00064

JSON explain

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