cp sql/ from GNU Taler exchange

include/sql/0002-unique_refresh_blinding_seed.sql

@@ -0,0 +1,72 @@
+--
+-- This file is part of TALER
+-- Copyright (C) 2025 Taler Systems SA
+--
+-- TALER is free software; you can redistribute it and/or modify it under the
+-- terms of the GNU General Public License as published by the Free Software
+-- Foundation; either version 3, or (at your option) any later version.
+--
+-- TALER is distributed in the hope that it will be useful, but WITHOUT ANY
+-- WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
+-- A PARTICULAR PURPOSE.  See the GNU General Public License for more details.
+--
+-- You should have received a copy of the GNU General Public License along with
+-- TALER; see the file COPYING.  If not, see <http://www.gnu.org/licenses/>
+--
+-- @author Özgür Kesim
+
+CREATE FUNCTION create_table_unique_refresh_blinding_seed(
+  IN partition_suffix TEXT DEFAULT NULL
+)
+RETURNS VOID
+LANGUAGE plpgsql
+AS $$
+DECLARE
+  table_name TEXT DEFAULT 'unique_refresh_blinding_seed';
+BEGIN
+  PERFORM create_partitioned_table(
+    'CREATE TABLE %I'
+      '(unique_refresh_blinding_seed_id BIGINT GENERATED BY DEFAULT AS IDENTITY'
+      ',blinding_seed BYTEA PRIMARY KEY'
+    ') %s ;'
+    ,table_name
+    ,'PARTITION BY HASH (blinding_seed)'
+    ,partition_suffix
+  );
+  PERFORM comment_partitioned_table(
+     'Table to ensure uniqueness of the blinding_seed for CS signatures across all refresh operations. '
+    ,table_name
+    ,partition_suffix
+  );
+END
+$$;
+
+
+CREATE FUNCTION constrain_table_unique_refresh_blinding_seed(
+  IN partition_suffix TEXT
+)
+RETURNS void
+LANGUAGE plpgsql
+AS $$
+DECLARE
+  table_name TEXT DEFAULT 'unique_refresh_blinding_seed';
+BEGIN
+  table_name = concat_ws('_', table_name, partition_suffix);
+  EXECUTE FORMAT (
+    'ALTER TABLE ' || table_name ||
+    ' ADD CONSTRAINT ' || table_name || '_refresh_id_key'
+    ' UNIQUE (unique_refresh_blinding_seed_id);'
+  );
+END
+$$;
+
+INSERT INTO exchange_tables
+  (name
+  ,version
+  ,action
+  ,partitioned
+  ,by_range)
+VALUES
+  ('unique_refresh_blinding_seed', 'exchange-0002', 'create',   TRUE ,FALSE),
+  ('unique_refresh_blinding_seed', 'exchange-0002', 'constrain',TRUE ,FALSE);
+