Comments in UltraLite

Comments are used to attach explanatory text to SQL statements or statement blocks. The UltraLite runtime does not execute comments.

The following comment indicators are available in UltraLite:

  • -- (Double hyphen)   The database server ignores any remaining characters on the line. This indicator is the SQL/2003 comment indicator.

  • // (Double slash)   The double slash has the same meaning as the double hyphen.

  • /* ... */ (Slash-asterisk)   Any characters between the two comment markers are ignored. The two comment markers may be on the same or different lines. Comments indicated in this style can be nested. This style of commenting is also called C-style comments.

    Note

    The percent sign (%) is not supported in UltraLite.

Examples
  • The following example illustrates the use of double-hyphen comments:
    CREATE TABLE borrowed_book (
       loaner_name CHAR(100)      PRIMARY KEY,
       date_borrowed DATE NOT NULL DEFAULT CURRENT DATE,
       date_returned       DATE,
       book                CHAR(20)
       FOREIGN KEY book REFERENCES library_books (isbn),
    );
    --This statement creates a table for a library database to hold information on borrowed books. 
    --The default value for date_borrowed indicates that the book is borrowed on the day the entry is made. 
    --The date_returned column is NULL until the book is returned.
  • The following example illustrates the use of C-style comments:
    CREATE TABLE borrowed_book (
       loaner_name CHAR(100)      PRIMARY KEY,
       date_borrowed DATE NOT NULL DEFAULT CURRENT DATE,
       date_returned       DATE,
       book                CHAR(20)
       FOREIGN KEY book REFERENCES library_books (isbn),
    );
    /* This statement creates a table for a library database to hold information on borrowed books. 
    The default value for date_borrowed indicates that the book is borrowed on the day the entry is made. 
    The date_returned column is NULL until the book is returned. */