Here is the answer you want

1。data analyst 和database analyst是一回事嗎？
Data Analyst/Database Analyst/Business Analyst/Reporting Engineer All above can be same in many companies

They all means you know some kind of database, you know how to generate report for the business.

2。比較一下SAP 和data analyst/database analys，那個更容易上手，更容易找工作,前途更穩定呢？

SAP is a Application software, you can only find job in the company where SAP is being use.

Database Analyst can find job in any company where database is being used.
So you know the answer.

3。沒有這些方麵的經驗，找工作容易嗎？(相對的說，in this bad economy, 找啥都不易哈)
-- You can pickup experience quickly in two or three months if you follow the right way. Yes, for sure.
-- Many people did it even they do not have software experience, you should be much better than they do.

Thanks!