haveInDatabase() is not usable inside a transaction on PostgreSQL

Our tables have PK sequences with different names than the ones postgres generates automatically. Because of that the lastInsertId() call inside haveInDatabase() generates a silent error.
When you use the method in a transaction, you don't see the actual error but the transaction is marked as "aborted" and you get exception and test fail on the next db statement. Without a transaction the test works fine but leaves other residues, which I hoped to clear by rollback. It took some time to debug and find the actual cause.

I did not find any warning about such limitation or previous mentions of it.

As a workaround I used INSERT .. RETURNING.

從 haveInDatabase() 進入點開始，在交易中使用 PostgreSQL 時追蹤 lastInsertId() 呼叫。使用名稱不同於 PostgreSQL 產生名稱的主鍵序列重現此情況，然後確認資料庫陳述式成功執行，且不會在未明確告知的情況下中止交易，後續陳述式也不會失敗。

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