Re: Synch/Asynch was Re: Expensive op codes

[Mark Lazarus <mlazarus@xxxxxxxx>]

John,

 Great explanation...  See below for questions.

At 08:44 PM 10/19/99 -0400, you wrote:

>Synchronous opcodes;  Chain, Reade, Readpe, Update, Delete 

>The READE has to read the index,  For each key index entry (which itself had
>to be brought into memory from DASD - ie DB page faults),

>So,  No blocking. Single record retreive on DB page fault.

>Record being asked for is loaded 1 at a time from memory to the Program's
>ODP work space.  
>No blocking again.

>-------
>Asynchronous functions   READ, READP opcodes, Straight output type (ie O in
>Fspec)

>The READ(for input only) doesn't concern itself with having to read the
>Index Object for what it wants,   It goes straight to the data space.
>Reading the data space consecutively.    Blocking is used.

 How is an indexed READ not reading the index object?  Why can't READE
behave similar to READ and leave it to the programmer to decide when it's
appropriate?

 -mark 

+---
| This is the RPG/400 Mailing List!
| To submit a new message, send your mail to RPG400-L@midrange.com.
| To subscribe to this list send email to RPG400-L-SUB@midrange.com.
| To unsubscribe from this list send email to RPG400-L-UNSUB@midrange.com.
| Questions should be directed to the list owner/operator: david@midrange.com
+---