Re: SQLCOD with Multiple Sql Statements and Best Practices for working with Logicals

[CRPence <CRPbottle@xxxxxxxxx>]

  Irrespective of the SQL DML statement, a habit that avoids naming a 
DDS keyed logical file anywhere in the statement, is best established. 
A keyed LF is effectively an SQL INDEX, which from a typical SQL 
perspective, would not even be eligible for being named in the DML.  At 
least primary in consideration for doing so, is that the optimization in 
selection & ordering of rows for the DML is redirected to the CQE for 
evaluation; IIRC, for any non-VIEW LF irrespective of keys, and I am 
unclear if\what might change with 6.1 of i.  Since the SQL Query Engine 
is intended to align better with the SQL language [as compared to the 
Classic Query Engine which was aligned also\more with Row Level Access], 
better optimization should be available from the SQE to perform the DML.

Regards, Chuck

Ala, Michael A wrote:
>  
> <<SNIP>>
> Is it okay to delete records from a LF that is just an alternate
> key of the Original Physical file 
> In general I try to perform Updates directly on the Physical file
> and Use LF for Input only
> Not sure why just something that I was told to do many years ago and
> continue to try to do today 
> Is there a real reason or am I just making my life more difficult.