DB2 10.5 for Linux, UNIX, and Windows

SQL comments

Static SQL statements can include host language or SQL comments. Dynamic SQL statements can include SQL comments.

There are two types of SQL comments:

simple comments: Simple comments are introduced by two consecutive hyphens (--) and end with the end of line.
bracketed comments: Bracketed comments are introduced by /* and end with */.

The following rules apply to the use of simple comments:

The two hyphens must be on the same line and must not be separated by a space.
Simple comments can be started wherever a space is valid (except within a delimiter token or between 'EXEC' and 'SQL').
Simple comments cannot be continued to the next line.
In COBOL, the hyphens must be preceded by a space.

The following rules apply to the use of bracketed comments:

The /* must be on the same line and must not be separated by a space.
The */ must be on the same line and must not be separated by a space.
Bracketed comments can be started wherever a space is valid (except within a delimiter token or between 'EXEC' and 'SQL').
Bracketed comments can be continued to subsequent lines.

Examples

Example 1: This example shows how to include simple comments in a statement:

   CREATE VIEW PRJ_MAXPER       -- PROJECTS WITH MOST SUPPORT PERSONNEL
     AS SELECT PROJNO, PROJNAME -- NUMBER AND NAME OF PROJECT
       FROM PROJECT
       WHERE DEPTNO = 'E21'     -- SYSTEMS SUPPORT DEPT CODE
       AND PRSTAFF > 1

Example 2: This example shows how to include bracketed comments in a statement:

   CREATE VIEW PRJ_MAXPER       /* PROJECTS WITH MOST SUPPORT
                                     PERSONNEL                 */
     AS SELECT PROJNO, PROJNAME /* NUMBER AND NAME OF PROJECT  */
       FROM PROJECT
       WHERE DEPTNO = 'E21'     /* SYSTEMS SUPPORT DEPT CODE   */
       AND PRSTAFF > 1