From 0854490c171a546c7dfd2c60618d8c3e1f58d6b6 Mon Sep 17 00:00:00 2001 From: "Karl O. Pinc kop@karlpinc.com" Date: Sat, 22 Feb 2025 23:04:46 +0000 Subject: [PATCH] Macros and replacement text for automatically generated column content --- db/include/macros.m4 | 22 ++++++++++++++++++++++ doc/src/epilog.inc.m4 | 6 ++++++ 2 files changed, 28 insertions(+) diff --git a/db/include/macros.m4 b/db/include/macros.m4 index 52cebed..5ae41ee 100644 --- a/db/include/macros.m4 +++ b/db/include/macros.m4 @@ -96,6 +96,28 @@ define({cannot_change}, {dnl END IF; }) changequote(`,') +dnl Plpgsql fragment for preventing values from being inserted into +dnl columns which have automatically generated values. +dnl This gets the user an error message instead of silently ignoring +dnl the inserted value. +dnl +dnl Syntax: inserted_null(table, column) +dnl Variables required: +dnl Restrictions: Must be used in a FOR EACH ROW insert trigger function. +changequote({,}) +define({inserted_null}, {dnl + IF NEW.$2 IS NOT NULL THEN + RAISE EXCEPTION data_exception USING + MESSAGE = 'Error updating $1' + , DETAIL = '($2) = (' + || NEW.$2 + || '): $1.$2 must be NULL upon INSERT' + , HINT = 'This column contains automatically generated content;' + ' insert NULL values or omit the column from the' + ' INSERT statement'; + END IF; +}) +changequote(`,') dnl Strings used in error messages dnl diff --git a/doc/src/epilog.inc.m4 b/doc/src/epilog.inc.m4 index a1975f8..ce0419a 100644 --- a/doc/src/epilog.inc.m4 +++ b/doc/src/epilog.inc.m4 @@ -313,6 +313,12 @@ sdb_generated_rst()dnl .. |cannot_change| replace:: The value of this column cannot be changed. +.. |system_maintained| replace:: + The value of this column is automatically maintained by the system. + Values inserted into this column must be |null| (or the column may + be omitted from the INSERT statement). + |cannot_change| + The value of this column is never |null|. .. |uppercase| replace:: This column may not contain lower case letters. -- 2.34.1