---
layout: article
title: MPE_DERIVED
description: The MPE_DERIVED table is used to configure computed columns that appear in the EDIT screen and can be filtered on without being stored in the table.
---

# MPE_DERIVED

!!! warning "Draft - not in a release yet"
    This page describes a feature that is in development. It is published early so
    the wording and the screenshots can be reviewed; the behaviour described here
    ships in the next release.

The MPE_DERIVED table is used to configure derived (computed) variables - columns that are created when a table is loaded into the EDIT screen, so that they can be displayed and filtered on without being stored.  More details are available in the [user guide](/derived-variables/)

The table is itself registered in [MPE_TABLES](/tables/mpe_tables/), so it is maintained through the EDIT screen with the usual review and approve workflow.

## Columns

 - `TX_FROM num`: SCD2 open datetime
 - 🔑 `TX_TO num`: SCD2 close datetime
 - 🔑 `LIBREF char(8)`: The libref of the target table
 - 🔑 `DSN char(32)`: The target table
 - 🔑 `VAR_NM char(32)`: The name of the derived column
 - `VAR_DEPS char(4000)`: Every input the expression uses - physical columns and derived variables, space separated
 - `VAR_TYPE char(1)`: `C` for character, `N` for numeric
 - `VAR_LEN num`: Character length, or numeric length (1-8)
 - `VAR_FMT char(32)`: Optional SAS format, eg `DATE9.`
 - `VAR_LABEL char(256)`: Optional label; defaults to `<VAR_NM>=<expression>`
 - `VAR_LOGIC char(4000)`: The SAS expression that produces the value
 - `ACTIVE num`: Set to 1 to apply the variable