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Accessing this data lets them make the right decisions and work faster. Comments are essential for developers because they have limited time, and commenting allows them to get valuable information at once or note some crucial details in regards to the code. It is mostly ignored by the compiler, but human specialists can read those comments when they view your code. Comments are used to add information to the code. In case the comments get stripped away, and assuming SELECT queries, a slight variation on the above would be to add a calculated column as the first thing. It is possible that mySQL server will remove this comment as part of its query analysis/preparation, but it may just leave it as well, so it shows as such in logs and other monitoring tools.

Comments can be placeholders when coding. But how exactly?In MySQL, the - (double-dash) comment style requires the second dash to be followed by at least one whitespace or control character (such as a space, tab. This post looks into the reasons for using query attributes, how it is done using a comment, and the new component for MySQL 8.0.23 that provides native support for query attributes.Comments are helpful for you personally and for anyone who may need to read or edit this code later.

It does not affect the final output as long as it comes before or after a definite pre-programmed character.To add comments in SQL, you can use the following symbols: /* */ or # or — (double-dash)./* */ will work for any situation where you want to start and end your comment at that point without using anything else (like single quotes).— also applies for one code line at a time. How to Comment in SQL?The comment function will let you write any text to add a comment in SQL. They’re typically just as easy to use anywhere else, too. This helps others understand how and why you did something so they can maintain or modify it as needed.Yes! Comments are most often used in conjunction with languages like SQL and PHP where we can insert them into a text file or script using the comment function * / (e.g., /* This is my comment */). Commenting allows you to make notes about what you’re doing.

You can think about them as somewhat similar to hashes – they reduce the time required to understand the code or identify some parts of it drastically by providing snippets that capture the essence of the text. Instead of the second, the younger version and the versions of the patch are substituted for the last 2.Only MySQL 5.1.10 or later version can run the following comments: CREATE TABLE t1 (Comments make programs easier to read by adding more details. It represents the minimum version of MYSQL that can execute commentaries.Instead of the first hash, substitute the main version of MYSQL. Select * from users /* this will list users */ Executable CommentsAs a rule, comments are ignored by whoever’s on the other end (because they’re for programmers only), but some comment types – executable comments – enable the code running on some systems.In our case, executable comments allow you to use SQL codes that will be executed in MYSQL only, not in other databases.Executable comments should be contained within asterisked slashes, as with the usual code:However, these executable comments require a specific syntax like below:You need the !# part to signal executable comments. Select * from users - this will list users Commenting Using the / * and * / SymbolsThis multiline commenting, unlike the previous two examples, doesn’t have to stop at the end of the line. The standard SQL doesn’t actually require you to use the space there, but MySQL uses it to avoid problems with commands like SELECT 10–1.