Comments - FastExport

Comment Topic

Description

Beginning and Ending Delimiters

A comment begins with a slash asterisk (/*) character sequence and ends with an asterisk slash (*/) sequence. All intervening text is treated as a comment.

Comment Destinations

Comments are always written to the message destination, and they may or may not be sent to Teradata Database.

Comments that are followed by a semicolon character are considered to be stand‑alone comments:

  /*Comment text*/;

  SELECT C1 FROM TABLE1;

In this case, the comment is associated with the SELECT statement and is sent to Teradata Database.

Invalid Within String or Character Literals

Comments cannot occur within string or character literals. A /* within a quoted string is not treated as the beginning of a comment.

Nested Comments

FastExport supports nested comments, but Teradata Database does not.

Always delimit nested comments with a semicolon character.

If a semicolon is used to delimit a nested comment, it is taken as part of the current command or statement. If that happens to be a Teradata SQL statement, it will be sent to Teradata Database, producing a syntax error.

Variable Substitution

Substitution of values for variable names continues within comments. Use two ampersand characters (&&) when the variable name is required.

Using Comments With Teradata SQL Statements

If a comment is used with a Teradata SQL statement, add a semicolon to the end of the comment if the comment should not be sent to Teradata Database.

If a semicolon is not used, FastExport sends the comment to Teradata Database along with the Teradata SQL statement.