You can add comments to SQL commands in order to clarify their intent.
The contents are text that does not formally belong to the SQL statements themselves.
You can add such comments in two ways: between /* and */ or after two consecutive minus signs.
Comments after two minus signs are implicitly ended by a newline character.
Comments between /* and */ can span multiple lines.
/* this text will be considered a comment,
this is the second line ... */
-- and this text too, until the end of this line.
You can add comments to database objects with the COMMENT command.