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SQL Comments

CamusDB accepts SQL comments in both common forms:

-- This comment runs to the end of the line.
SELECT id, name
FROM robots;

SELECT id, name
FROM robots /* inline block comment */
WHERE year >= 1980;

/*
  Block comments can span multiple lines.
*/
SELECT COUNT(*) FROM robots;

Comments are ignored by the parser anywhere whitespace would be valid. This means you can place comments before a statement, between clauses, or at the end of a line.

Line Comments​

Line comments start with -- and continue to the end of the line:

SELECT id, name
FROM robots
WHERE year >= 1980; -- only newer robots

A comment-only input is not a valid SQL statement, but it is handled as a normal parse error rather than a lexer failure.

Block Comments​

Block comments start with /* and end with */:

SELECT id, name
FROM robots
/* keep this filter aligned with the dashboard */
WHERE active = true;

Block comments can span multiple lines:

/*
  Report all active robots
  visible to the current query.
*/
SELECT id, name
FROM robots
WHERE active = true;

Block comments are not nested. The first */ closes the comment. An unterminated block comment raises a parse error.

Comments In Strings​

Comment markers inside quoted string literals are treated as string content, not as comments:

SELECT "not -- a comment" AS value;
SELECT "not /* a comment */" AS value;

Operators​

Comment parsing does not change arithmetic operator behavior:

SELECT 10 - -5 FROM numbers;
SELECT a / b FROM metrics;
SELECT a * b FROM metrics;

The sequence -- starts a line comment. For example, SELECT 10 FROM t --5 parses as SELECT 10 FROM t with --5 treated as a comment.