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

mysql update increment int field that is null

I have a very large table with two INT columns that are null on Default. This is a problem because since they are INT fields, it would help in many cases if they were originally set to 0.

So my questions are, is there a way I can UPDATE and INCREMENT(+1) these fields while they are like this (null on Default)? BTW.. I didn't have luck so far, it seems increment only works when the default=0

..or is my only option to Change the Default to none from null

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)
UPDATE TableName SET column = IFNULL(column, 0) + 1 WHERE ...

More info on IFNULL. It returns the first argument if it is not NULL, the second otherwise.


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

...