SQL/MP Reference Manual

HP NonStop SQL/MP Reference Manual—523352-013
C-48
COMMENT Statement
23) were added in version 2, and the columns CPRULESNAME through
CHARACTERSET (24 through 26) were added in version 300.
The COLUMNS table has a set of column entries for each partition of a partitioned
table.
All CHAR and VARCHAR fields in the COLUMNS table except for HEADING and
HEADINGTEXT use uppercase characters. Guardian names in the table are fully
qualified.
COMMENT Statement
COMMENT is a DDL statement that writes a comment about a collation, column,
constraint, index, table, or view to the catalog. For partitioned objects, COMMENT
adds the comment for each partition. COMMENT can add a new comment or delete,
replace, or add to existing comments.
comment
is the comment, expressed as a string of single-byte or double-byte characters
enclosed in single or double quotation marks. It can be 0 to 132 bytes long.
CLEAR
purges existing comments before adding the new comment.
The other clauses identify the object to which the comment applies.
Considerations—COMMENT

To use COMMENT on a collation, column, table, or view you must be a
generalized owner of the table or view. To use COMMENT on an index, you must
be a generalized owner of the underlying table. COMMENT also requires authority
to write to the affected catalogs.
Only one DDL statement can operate on a given SQL object (or partition of an SQL
object) at a time. An error occurs if you attempt to execute a COMMENT statement
while another process is executing a DDL operation on the same object. The
specific error depends on the DDL operation involved and the phase of the
operation at which the conflict occurs. (For more information, see DDL (Data
Definition Language) Statements on page D-20.)
{ COLLATION collation }
{ COLUMN column ON { table | view } }
COMMENT ON { CONSTRAINT constraint ON table }
{ INDEX index }
{ TABLE table }
{ VIEW view }
IS comment [ CLEAR ]