From 64c3fb51aaabbcc03e2a24b23150e5e310a8ba4e Mon Sep 17 00:00:00 2001 From: dc Date: Wed, 21 Oct 2026 22:20:04 +0000 Subject: [PATCH] docs(derived): correct the collision rule TX_FROM, TX_TO and PROCESSED_DTTM are the default names of the metadata columns rather than reserved names - they are physical columns, refused by the collision check whatever MPE_TABLES calls them. The only name refused outright is the delete marker. The code now matches: the hard-coded list is gone. --- docs/derived-variables.md | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/docs/derived-variables.md b/docs/derived-variables.md index f9bbc15..aeb062e 100644 --- a/docs/derived-variables.md +++ b/docs/derived-variables.md @@ -118,7 +118,7 @@ Derived columns themselves are an EDIT screen feature: the VIEW screen and the d - **Expressions only.** `VAR_LOGIC` must be a single SAS expression - no semicolons, macro triggers (`%`, `&`) or comments. Conditional logic is available through functions such as `ifc()`, `choosec()`, `cats()`, `catx()`, `put()`, `input()` and `intnx()`. - **Dependencies declared.** `VAR_DEPS` lists every input the expression uses, physical columns and derived variables alike. Statements are generated in dependency order, so a variable can build on another without a sequence number. The declaration is checked against the expression in both directions: a derived variable that is referenced must be declared, and a declared name that the expression does not reference is an error. A declared name must be a column of the table or a derived variable of the same table, and a cycle is rejected. - - **No collisions.** `VAR_NM` must not match an existing column of the target table, or one of the reserved names (`TX_FROM`, `TX_TO`, `PROCESSED_DTTM`, `VAR_TXFROM`, `VAR_TXTO`, `VAR_PROCESSED`, `_____DELETE__THIS__RECORD_____`). + - **No collisions.** `VAR_NM` must not match an existing column of the target table. That includes the metadata columns Data Controller adds, whatever [MPE_TABLES](/tables/mpe_tables/) names them - `TX_FROM`, `TX_TO` and `PROCESSED_DTTM` by default, `VER_FROM_DTTM` and `VER_TO_DTTM` for a bitemporal table for example. The one name always refused is `_____DELETE__THIS__RECORD_____`, which the EDIT grid uses to mark a row for deletion. - **Read-only.** Derived columns cannot be edited in the grid, and any value submitted for them is discarded before the approval package is created. - **Recomputed on every read.** The value always reflects the current data and the current definition, and there is no history of previous derived values.