ALTER TABLE "SalesInquiry"
ADD COLUMN IF NOT EXISTS "invoiceId" TEXT;

CREATE INDEX IF NOT EXISTS "SalesInquiry_invoiceId_idx"
ON "SalesInquiry"("invoiceId");

DO $$
BEGIN
  IF NOT EXISTS (
    SELECT 1
    FROM pg_constraint
    WHERE conname = 'SalesInquiry_invoiceId_fkey'
  ) THEN
    ALTER TABLE "SalesInquiry"
    ADD CONSTRAINT "SalesInquiry_invoiceId_fkey"
    FOREIGN KEY ("invoiceId")
    REFERENCES "Invoice"("id")
    ON DELETE SET NULL
    ON UPDATE CASCADE;
  END IF;
END $$;