Welcome to OGeek Q&A Community for programmer and developer-Open, Learning and Share
Welcome To Ask or Share your Answers For Others

Categories

0 votes
362 views
in Technique[技术] by (71.8m points)

sql server - Should there be a Transaction for Read Queries?

I've been reading that some devs/dbas recommend using transactions in all database calls, even read-only calls. While I understand inserting/updating within a transaction what is the benefit of reading within a transaction?

See Question&Answers more detail:os

与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
Welcome To Ask or Share your Answers For Others

1 Reply

0 votes
by (71.8m points)

So you get a consistent view of the database. Imagine you have two tables that link to each other, but for some reason you do 2 selects... in pseuodocode:

myRows = query(SELECT * FROM A)
moreRows = query(SELECT * FROM B WHERE a_id IN myRows[id])

If between the two queries, someone changes B to delete some rows, you're going to have a problem.


与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
OGeek|极客中国-欢迎来到极客的世界,一个免费开放的程序员编程交流平台!开放,进步,分享!让技术改变生活,让极客改变未来! Welcome to OGeek Q&A Community for programmer and developer-Open, Learning and Share
Click Here to Ask a Question

...