PL/SQL supports two comment styles: single-line and multi-line. A double hyphen (
- -) anywhere on a line (except within a character literal) turns the rest of the line into a comment. Multi-line comments begin with a slash-asterisk (
/*) and end with an asterisk-slash (
*/). For more information, see "Comments".
While testing or debugging a program, you might want to disable lines of code. Single-line comments can appear within a statement at the end of a line. You can include single-line comments inside multi-line comments, but you cannot nest multi-line comments.
You cannot use single-line comments in a PL/SQL block that will be processed dynamically by an Oracle Precompiler program. End-of-line characters are ignored, making the single-line comments extend to the end of the block. Instead, use multi-line comments. You can use multi-line comment delimiters to comment-out whole sections of code.
For examples, see the following: