mechanism does not support these object types.

<literal>ddl_command_start</> also occurs just before the execution of a

<literal>SELECT INTO</literal> command, since this is equivalent to

<literal>CREATE TABLE AS</literal>.

<literal>CREATE TABLE AS</literal>. The <literal>ddl_command_end</>

event occurs just after the execution of this same set of commands.

</para>

<para>

The <literal>ddl_command_end</> event occurs just before returning

control from the execution of a <literal>CREATE</>, <literal>ALTER</>,

or <literal>DROP</> command. It shares the same exceptions as

the <literal>ddl_command_start</> event.

Event triggers (like other functions) cannot be executed in an aborted

transaction. Thus, if a DDL command fails with an error, any associated

<literal>ddl_command_end</> triggers will not be executed. Conversely,

if a <literal>ddl_command_start</> trigger fails with an error, no

further event triggers will fire, and no attempt will be made to execute

the command itself. Similarly, if a <literal>ddl_command_end</> trigger

fails with an error, the effects of the DDL statement will be rolled

back, just as they would be in any other case where the containing

transaction aborts.

</para>

<para>