COMMENT ON

This SQL statement can be executed in the following ways:	Through the CA Datacom Datadictionary Interactive SQL Service Facility (interactive)	In an application program prepared using a CA Datacom/DB SQL Preprocessor (embedded)	By using CA Dataquery (SQL & Batch Modes)
COMMENT ON	YES	YES	YES

Note: YES indicates a valid execution method for this statement. To learn about using SQL keywords in CA Dataquery, see the CA Dataquery User Guide. For information about the access rights required to execute this statement, see the CA Datacom/DB Database and System Administration Guide.

The COMMENT ON statement is a CA Datacom/DB extension. COMMENT ON adds or replaces comments in CA Datacom Datadictionary. The comments apply to tables, views or columns.

If a comment does not exist for the table, view or column, the comment you specify is added to text in CA Datacom Datadictionary. If a comment already exists for the table, view or column, and you specify a new comment, the existing comment is replaced by the new comment.

You cannot retrieve a comment through SQL. You can display the text created by the COMMENT ON statement through the CA Datacom Datadictionary batch and online functions. See the CA Datacom Datadictionary User Guide for information about displaying text.

CA Datacom Datadictionary provides many capabilities not available through SQL. For example, text classifications allow you to store text about your SQL tables, views and columns in addition to that specified in the COMMENT ON statement. See the CA Datacom Datadictionary User Guide for more information about specifying additional text.

Following is the syntax diagram for the COMMENT ON statement:

►►─ COMMENT ON ───────────────────────────────────────────────────────────────►

 ►─┬─ TABLE ─┬─ table-name ─┬IS ─ string-literal ────────────────┬────────────►◄
   │         └─ view-name ──┘                                    │
   ├─ COLUMN ─┬─ table-name.column-name ─┬IS ─ string-literal ───┤
   │          └─ view-name.column-name ──┘                       │
   │                      ┌─ , ────────────────────────────┐     │
   └─┬─ table-name ─┬─ ( ─▼─ column-name ─ string-literal ─┴─ ) ─┘
     └─ view-name ──┘