2014-09-17 21:36 GMT+02:00 Peter Eisentraut <pete...@gmx.net>: > On 9/17/14 3:04 PM, Pavel Stehule wrote: > > What is difference between content of variable or content of database? > > You can test any prerequisite, but when this prerequisite is not solved, > > than exception is very very hard without possible handling. > > If the assertion tests arbitrary Boolean expressions, then we can't stop > the user from abusing them. > > I am thinking so unhandled signal can be good defence. (and possibility to disable assertions)
We design a database system, so we should to reflect it - plpgsql (or any PL environment) are not classic language. There are lot of database specific constructs. > But it's another thing if we design specific syntax that encourages such > abuse, as proposed earlier. > > Other note - I am thinking so ANSI SQL Assertions and PL assertions are independent features. Although they can have some common goals.