Re: . RPG and SQL view/index (Timothy Feldmeier) -- RPG400-L

I don't know what a Logical View is, not a Table View, nor a Table Index - I don't think any of those exist in IBM's terminology - as Charles says, there are the 3 SQL object types and basically 2 DDS types.

SQL tables are implemented as PFs with a special set of attributes - the benefit of our object-based OS.
SQL views and indexes are implemented as LFs with their special set of attributes.

I figured pictures are more informative -

I ran the following SQL DDL statements -

CREATE OR REPLACE VIEW vhamberg.cuscdtnomn AS SELECT * FROM qiws.qcustcdt WHERE STATE <> 'MN';
CREATE INDEX vhamberg.cuscdtbyst on qiws.qcustcdt (state);

These are the resulting objects as seen in PDM -

CUSCDTBYST *FILE LF
CUSCDTNOMN *FILE LF

Here is the file description of the index - note the SQL file type - an LF created with CRTLF does not have that attribute - the access path names the column, STATE -

Data Base File Attributes
Externally described file . . . . . . . . . : Yes
SQL file type . . . . . . . . . . . . . . . : INDEX
File level identifier . . . . . . . . . . . : 1210708194429
Creation date . . . . . . . . . . . . . . . : 07/08/21

Here is the same for the view - again, note the SQL file type - the SELECT statement is in the file description and follows -

Data Base File Attributes
Externally described file . . . . . . . . . : Yes
SQL file type . . . . . . . . . . . . . . . : VIEW
File level identifier . . . . . . . . . . . : 1210708194414
Creation date . . . . . . . . . . . . . . . : 07/08/21

SQL view create statement . . . . . . . . . :
-- category: Data Definition Language (DDL)
-- description: Crea
te or Replace View
CREATE VIEW CUSCDTNOMN AS SELECT * FROM QIWS.QCU
STCDT WHERE STATE <> 'MN'

Nothing of these is a one-time, static thing - every time the object is used, the data at the time is presented.

So even in DDS, what is a one-time build? PFs and LFs are always presented as what their content is at the time of use.

So what am I missing? I just don't know anything that is one-time - help me understand - seriously!

Regards
Vern

On 7/8/2021 4:40 PM, Charles Wilt wrote:

There's no such thing as a "table view"

In SQL DDL, there are TABLES, VIEWS, and INDEXES.
In DDS, there are Physical files and Logicals files (ok and DDM). With
logical files subset into keyed/non-keyed and dynamic/non-dynamic
Select/Omit.

-snip-

Charles

On Thu, Jul 8, 2021 at 11:37 AM Timothy Feldmeier <
Timothy.Feldmeier@xxxxxxxx> wrote:

Vern, you are referring to a Logical View. I am referring to a Table
View. They are a 1 time build. An Table Index would always be up to date.
This is the difference between DDS and DDL. Create View vs Create
Index.

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