%SELECTALL

If you ever need to create a view that selects all fields from a particular record, then you should be using the %SelectAll meta-sql construct.

Why? Because %SelectAll uses the underlying record definition to select the fields - so it will always return all fields from the underlying record, even if that record definition changes.

The basic syntax is:

  • %SelectAll(RECORD_NAME ALIAS)

There is all a %SelectDistinct construct which adds a distinct to the select clause and uses the same syntax.

%SelectAll returns all the fields for the record specified and includes a from clause.

For example, say I want the latest effective dated, active fields from PSXLATITEM. My SQL might start something like this:

select FIELDNAME, FIELDVALUE, EFFDT, EFF_STATUS, XLATLONGNAME, XLATSHORTNAME, LASTUPDDTTM, LASTUPDOPRID, SYNCID from PSXLATITEM A where EFFDT = ( select max(EFFDT) from PSXLATITEM where FIELDNAME = A.FIELDNAME and FIELDVALUE = A.FIELDVALUE and A.EFFDT <= sysdate ) and A.EFF_STATUS = 'A';

Instead of typing out all those fields, lets use %SelectAll - that's what I did to generate this example btw ;)

So our meta-sql would look like this - (I've also replaced sysdate with %CurrentDateIn)

%SelectAll(PSXLATITEM A)where EFFDT = ( select max(EFFDT) from PSXLATITEM where FIELDNAME = A.FIELDNAME and FIELDVALUE = A.FIELDVALUE and A.EFFDT <= %CurrentDateIn ) and A.EFF_STATUS = 'A'

Note that %SelectAll wraps date, time and date/time fields with %DateOut%TimeOut%DateTimeOut as well. This resolves into the following meta-sql:

SELECT A.FIELDNAME , A.FIELDVALUE , TO_CHAR(A.EFFDT ,'YYYY-MM-DD') , A.EFF_STATUS , A.XLATLONGNAME , A.XLATSHORTNAME , TO_CHAR(A.LASTUPDDTTM ,'YYYY-MM-DD-HH24.MI.SS."000000"') , A.LASTUPDOPRID , A.SYNCID FROM PSXLATITEM A WHERE EFFDT = ( SELECT MAX(EFFDT) FROM PSXLATITEM WHERE FIELDNAME = A.FIELDNAME AND FIELDVALUE =A.FIELDVALUE AND A.EFFDT <= TO_DATE(TO_CHAR(SYSDATE,'YYYY-MM-DD'),'YYYY-MM-DD') ) AND A.EFF_STATUS = 'A'

Note that the example includes an alias of A in the parameters to %SelectAll. If you are using %SelectAll you might have to play with your SQL a bit to get it work, especially if you are using joins to other tables. It may not work in all cases, but if nothing else, its a time saver!

posted @ 2013-10-24 13:55  Bryan chen  阅读(314)  评论(0编辑  收藏  举报