On Sun, Jan 12, 2014 at 07:00:09AM +0100, Pavel Stehule wrote: > Comment updated. Patch attached. > > > > Still I am missing message about preferred syntax (or we should to enhance GET > DIAGNOSTICS doc about proprietary syntax). > > PL/pgSQL, PL/SQL is mix of two languages: ADA and SQL - and their designers > decided so embedded SQL statements will be placed in native SQL syntax (and ADA > in simplified ADA syntax) > > We have to find a agreement what we will prefer for PL/pgSQL: > > The assign statement is "ADA" statement - ":=" is preferred > > The GET DIAGNOSTICS is "SQL" statement - "=" is preferred > > A newer SQL/PSM was designed differently - without this dichotomy - A > assignment is emphased by syntax SET varname = value > > A proper syntax is good information what is coming from - and It is good mental > helper to understand a philosophy of stored procedures (that shares concepts > with PL/SQL). Next argument is similarity with PL/SQL and SQL PL. This > statement (GET DIAGNOSTICS) is supported on both environments and only "=" is > allowed there.
I find the rules above so complex that I don't see how we can recommend a best syntax. What I did in the patch I just posted was to put the preferred operator first, but I don't see why we want to get into these details in the docs.
just a note about preferred variant should be ok. Using ':=' in GET DIAGNOSTICS statement is just bad idea.
