LP#1569884 Allow deleted monograph parts to be recreated.

Changed the constraint on the biblio.monograph_part table to allow for a
monograph part to be created if a duplicate deleted version is found.

To test:

[1] Add a monograph part to a bib.
[2] Delete that monograph part.
[3] Attempt to add a monograph part to the same bib using
    the same part label. Without the patches installed, this
    will fail; upon applying the database update, this operation
    should succeed.

Signed-off-by: Steven Callender <stevecallender@esilibrary.com>
Signed-off-by: Jason Stephenson <jstephenson@mvlcstaff.org>
Signed-off-by: Galen Charlton <gmc@esilibrary.com>

diff --git a/Open-ILS/src/sql/XXXX.schema.allow_parts_to_be_recreated.sql b/Open-ILS/src/sql/XXXX.schema.allow_parts_to_be_recreated.sql
new file mode 100644 (file)
index 0000000..235a5f0
--- /dev/null
+++ b/Open-ILS/src/sql/XXXX.schema.allow_parts_to_be_recreated.sql
@@ -0,0 +1,8 @@
+BEGIN;
+
+SELECT evergreen.upgrade_deps_block_check('XXXX', :eg_version);
+
+ALTER TABLE biblio.monograph_part DROP CONSTRAINT "record_label_unique";
+CREATE UNIQUE INDEX CONCURRENTLY record_label_unique_idx ON biblio.monograph_part (record, label) WHERE deleted = FALSE;
+
+COMMIT;