diff --git a/doc/src/sgml/ref/notify.sgml b/doc/src/sgml/ref/notify.sgml index 92310c0d8ce82e727639c56f27dfb1ecf74c797b..0404de2c308a74755b52defd0864c9b27dd3ba83 100644 --- a/doc/src/sgml/ref/notify.sgml +++ b/doc/src/sgml/ref/notify.sgml @@ -147,16 +147,16 @@ after the transaction is completed (either committed or aborted). Again, the reasoning is that if a notify were delivered within a transaction that was later aborted, one would want the notification to be undone somehow --- but the backend cannot "take back" a notify once it has sent it to the frontend. -So notify events are delivered only between transactions. The upshot of this +So notify events are only delivered between transactions. The upshot of this is that applications using <command>NOTIFY</command> for real-time signaling should try to keep their transactions short. <para> -<command>NOTIFY</command> behaves rather like Unix signals in one important -respect: if the same notify name is signaled multiple times in quick +<command>NOTIFY</command> behaves like Unix signals in one important +respect: if the same condition name is signaled multiple times in quick succession, recipients may get only one notify event for several executions of <command>NOTIFY</command>. So it is a bad idea to depend on the number -of notifies received; instead use <command>NOTIFY</command> to wake up +of notifies received. Instead, use <command>NOTIFY</command> to wake up applications that need to pay attention to something, and use a database object (such as a sequence) to keep track of what happened or how many times it happened. @@ -201,8 +201,8 @@ table name, even if syntactically valid as a name. That is no longer required. <para> In <productname>Postgres</productname> releases prior to 6.4, the backend -PID delivered in a notify message is always the PID of the frontend's own -backend. So it is not possible to distinguish one's own notifies from other +PID delivered in a notify message was always the PID of the frontend's own +backend. So it was not possible to distinguish one's own notifies from other clients' notifies in those earlier releases. </REFSECT2>