What are the three ways to write mysql notes
What are the three ways to write mysql notes? This problem may be often seen in our daily study or work. I hope you can gain a lot from this question. The following is the reference content that the editor brings to you, let's take a look at it!
There are three kinds of comments in mysql, which are: 1, single-line comments using "# comment content"; 2, single-line comments using "--comment content" with a space between "-" and comment content; 3, multi-line comments using "/ * comment content * /".
Generally speaking, there are three annotation styles in MySQL, which are:
1. Single-line comments can be made with "#"
Select 1 as cname; # this is a comment +-+ | cname | +-+ | 1 | +-+-(comments are directly followed by #)
2. The second way to write a single-line comment is to use "-"
Note that in this style, there is a space between "- -" and the comment.
Select 123;-- this is a comment +-+ | 123 | +-+ | 123 | +-- pay attention-- there should be a space after it.
3. Multi-line comments can be made with / * /
Mysql > select 123; / * this is a comment * / +-+ | 123 | +-+ | 123 | +-+ 1 row in set (0.00 sec) mysql > select 1 + / * this is a comment * / 1 sec + | 1 + 1 | +-+ | 2 | +-+ 1 row in set (0.00 sec) Thank you for reading! After reading the above, do you have a general understanding of the three ways of writing mysql notes? I hope the content of the article will be helpful to all of you. If you want to know more about the relevant articles, you are welcome to follow the industry information channel.