feat(BE-229,234,235,230,231,232,233): purchase request and purchase order and fix master data dto

internal/database/migrations/20251104084555_purchases.up.sql

@@ -1,17 +1,19 @@
 CREATE TABLE IF NOT EXISTS purchases (
     id BIGSERIAL PRIMARY KEY,
     pr_number VARCHAR NOT NULL,
-    po_number VARCHAR,
-    po_date TIMESTAMPTZ,
+    po_number VARCHAR NULL,
+    po_date TIMESTAMPTZ NULL,
     supplier_id BIGINT NOT NULL,
-    credit_term INT,
+    credit_term INT NOT NULL,
     due_date TIMESTAMPTZ,
-    grand_total NUMERIC(15, 3) DEFAULT 0,
+    grand_total NUMERIC(15, 3) NOT NULL,
     notes TEXT,
-    created_at TIMESTAMPTZ DEFAULT NOW(),
-    updated_at TIMESTAMPTZ DEFAULT NOW(),
+    created_at TIMESTAMPTZ NOT NULL,
+    updated_at TIMESTAMPTZ NOT NULL,
     deleted_at TIMESTAMPTZ,
-    created_by BIGINT NOT NULL
+    created_by BIGINT NOT NULL,
+    CONSTRAINT uq_purchases_pr_number UNIQUE (pr_number),
+    CONSTRAINT uq_purchases_po_number UNIQUE (po_number)
 );
 
 DO $$
@@ -50,14 +52,6 @@ BEGIN
     END IF;
 END $$;
 
-CREATE UNIQUE INDEX IF NOT EXISTS idx_purchases_pr_number_unique
-    ON purchases (pr_number)
-    WHERE deleted_at IS NULL;
-
-CREATE UNIQUE INDEX IF NOT EXISTS idx_purchases_po_number_unique
-    ON purchases (po_number)
-    WHERE deleted_at IS NULL AND po_number IS NOT NULL;
-
 CREATE INDEX IF NOT EXISTS idx_purchases_supplier_id ON purchases (supplier_id);
 CREATE INDEX IF NOT EXISTS idx_purchases_created_by ON purchases (created_by);
 CREATE INDEX IF NOT EXISTS idx_purchases_po_date ON purchases (po_date);