Merge pull request #14654 from opf/restore_project_script_ignore_conf…

…licts

ignore conflicts when restoring a deleted project

docs/installation-and-operations/operation/restoring/restoring-a-deleted-project/README.md

@@ -11,6 +11,20 @@ The following files will be used in the examples.
 
 There is also a script ([restore.sh](./restore.sh)) that shows how to use everything together.
 
+## 0. Prerequisites
+
+* you have a Backup of your OpenProject installation with the missing data still present
+* you have restored the database dump of this backup into a new, separate database called `openproject_backup`
+  * Created, for instance, via
+    * `psql -c 'create database openproject_backup'`
+    * `pg_restore -d openproject_backup openproject.pgdump`
+* your present OpenProject database is called `openproject`
+
+It does not matter where the actual Postgres server is running.
+In all the following examples we simply use `psql -d openproject_backup` and `psql -d openproject` respectively. Where `openproject_backup` and `openproject` are the names of the databases within Postgres.
+
+In your case you may have to provide more options (e.g. the user or host) to connect to the respective database.
+
 ## 1. Dump project data from backup
 
 First we copy the data from the backup, that was deleted later.

docs/installation-and-operations/operation/restoring/restoring-a-deleted-project/dump.sql

@@ -59,9 +59,6 @@ FOR source_table, source_column IN (
   from information_schema.columns
   where table_schema = 'public' and column_name = 'project_id'
     and table_name not like '%_journals'
-    and table_name != 'grids'
-    -- apparently grids do not get deleted when a project is which is why we skip them here
-    -- otherwise there will be an 'already exists' error during restoration later
 )
 LOOP
   EXECUTE 'CREATE TABLE missing_' || source_table || ' AS (' ||

docs/installation-and-operations/operation/restoring/restoring-a-deleted-project/restore.sql

@@ -5,6 +5,8 @@ BEGIN;
 DO
 $$
 DECLARE table_to_copy TEXT;
+DECLARE primary_keys TEXT;
+DECLARE insert_sql TEXT;
 BEGIN
 FOR table_to_copy IN (
   select table_name
@@ -16,8 +18,25 @@ FOR table_to_copy IN (
 LOOP
   raise notice 'Restoring % to %', table_to_copy, REPLACE(table_to_copy, 'missing_', '');
 
-  EXECUTE 'INSERT INTO ' || REPLACE(table_to_copy, 'missing_', '') ||
-    ' (SELECT * FROM ' || table_to_copy || ');';
+  -- get primary keys for table
+  SELECT STRING_AGG(a.attname, ',') AS TEXT INTO primary_keys
+  FROM   pg_index i
+  JOIN   pg_attribute a 
+  ON a.attrelid = i.indrelid AND a.attnum = ANY(i.indkey)
+  WHERE  i.indrelid = REPLACE(table_to_copy, 'missing_', '')::regclass
+  AND    i.indisprimary;
+
+
+  insert_sql := 'INSERT INTO ' || REPLACE(table_to_copy, 'missing_', '') ||
+    ' (SELECT * FROM ' || table_to_copy || ')';
+
+  -- do nothing on conflict if a primary key exists
+  IF primary_keys IS NOT NULL
+  THEN
+   insert_sql := (insert_sql || ' ON CONFLICT ('|| primary_keys ||') DO NOTHING');
+  END IF;
+
+  EXECUTE (insert_sql || ';');
 END LOOP;
 END;
 $$;