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.

从 haveInDatabase() 入口点开始，在事务中使用 PostgreSQL 时跟踪 lastInsertId() 调用。使用名称不同于 PostgreSQL 生成名称的主键序列复现该情况，然后验证数据库语句是否成功执行而不会静默中止事务，并且后续语句不会失败。

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