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
893 views
in Technique[技术] by (71.8m points)

database - Predict next auto-inserted row id (SQLite)

I'm trying to find if there is a reliable way (using SQLite) to find the ID of the next row to be inserted, before it gets inserted. I need to use the id for another insert statement, but don't have the option of instantly inserting and getting the next row.

Is predicting the next id as simple as getting the last id and adding one? Is that a guarantee?

Edit: A little more reasoning... I can't insert immediately because the insert may end up being canceled by the user. User will make some changes, SQL statements will be stored, and from there the user can either save (inserting all the rows at once), or cancel (not changing anything). In the case of a program crash, the desired functionality is that nothing gets changed.

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)

Try SELECT * FROM SQLITE_SEQUENCE WHERE name='TABLE';. This will contain a field called seq which is the largest number for the selected table. Add 1 to this value to get the next ID.

Also see the SQLite Autoincrement article, which is where the above info came from.

Cheers!


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

...