Comments

One of the annoying things about working with multiple languages is they each have their differences – obviously, otherwise there would only be 1 language! Although there is good reason to have these differences they still have elements that are a pain. One of the most annoying things, other then “do you require a semicolon at the end of the statement?” is comments. Comments aren’t executed or complied but they help developers read code. Remember, the code is a interpretive language, its designed to be gateway between the machines and humans, if you write something complex your more then likely need to be include more comments explain what it does or look at refactoring so other developers can continue your work.

The few options are:

Double dash (–)

— Single line quote

Single Hash (#)

# Single line quote

Double forward-slash (//)

// string domain = “matt40k.uk”;

All of these are single line quotes, as in each line needs the require comment and the comment continues till the end of the line \ carriage break.

You also got:

Forward-slash and asterisk (/*)

/* Multi-Line

quote */

Forward-slash and asterisk marks (/) the start of the comment, the comment continues until the asterisk marks and Backward-slash (/). The code must close any open Forward-slash and asterisk marks (/*) comments in order to compile.

With Forward-slash and asterisk, you can comment in-line, for example

Select * from /* Change the code to the right */ sys.tables

This is valid T-SQL that will return the all the columns for meta data about tables on the selected database

You can also use this across multiple lines, for example

select

TableSchema = schema_name(schema_id)

,TableName = name

/*

You could also add

other tables

 

*/

from

sys.tables

Power Query Formula (M) Language

Double dash (–) No

Single hash (#) Yes

Double forward-slash (//) No

Forward-slash and asterisk (/*) Yes

Transact-SQL (TSQL)

Double dash (–) Yes

Single hash (#) No

Double forward-slash (//) No

Forward-slash and asterisk (/*) Yes

C sharp (C#)

Double dash (–) No

Single hash (#) No

Double forward-slash (//) Yes

Forward-slash and asterisk (/*) Yes

Fun fact, my most commonly used comment?

To-Do