Comments may be present in SQL scripts, SQL statements and PSQL modules. A comment can be any text, usually used to document how particular parts of the code work. The parser ignores the text of comments.

Firebird supports two types of comments: block (or bracketed) and in-line (or simple).

Syntax

<comment> ::= <block comment> | <single-line comment>
 
<block comment> ::=
  /* <character>[<character> ...] */
 
<single-line comment> ::=
  -- <character>[<character> ...]<end line>

Block comments start with the /* character pair and end with the */ character pair. Text in block comments may be of any length and can occupy multiple lines.

In-line comments start with a pair of hyphen characters, -- and continue until the first linebreak (end of line).

Example

CREATE PROCEDURE P(APARAM INT)
  RETURNS (B INT)
AS
BEGIN
  /* This text will be ignored during the execution of the statement
     since it is a comment
  */
  B = A + 1; -- In-line comment
  SUSPEND;
END