课程: Access 2016 Essential Training

今天就学习课程吧！

今天就开通帐号，24,700 门业界名师课程任您挑！

Understanding queries

Understanding queries

课程: Access 2016 Essential Training

开始一个月试用 购买团队方案

Understanding queries

“

- Queries and Access are where a lot of the magic of the database comes to life, and truth be told, they're one of my favorite components of any database, but if you've never worked with them before, then you might be wondering, "Well, what exactly is a query?" Simply put, queries are a very powerful way to ask questions about your data. You'll do this by pulling information out of your existing data tables and combining that data into new configurations on the fly. Queries return answers in the form of a temporary datasheet, but they don't take up any additional storage space in the database because they only store the instruction on how to reassemble your existing data and don't store data of their own. And every time you run a query, it fetches the current state of the data from the source tables, so they're always up-to-date. One of the best features of a query, though, is that they look and function just like regular tables, so you can connect them to forms and reports in exactly…

内容