Обсуждение: Documenting NULLVALUE() and NONNULLVALUE()
Perl and PHP programmers (such as myself) are accustomed to using defined()/isset() and so when wanting to test null value they might look to the Functions chapter (9) instead of the SQL Syntax chapter (4). It took me some time before I found out about ISNULL, IS NULL, NOTNULL, IS NOT NULL. In MySQL I am accustomed to using ISNULL() function. Perhaps we can change section 9.1 from "Logical Operators" to "Logical Functions and Operators"? NULLVALUE() and NONNULLVALUE() can be documented there, along with IS, IS NULL, and IS NOT NULL (which also don't seem to have been covered yet in Chapter 9). Should I submit a patch? -- dave
David Garamond <lists@zara.6.isreserved.com> writes: > Perhaps we can change section 9.1 from "Logical Operators" to "Logical > Functions and Operators"? NULLVALUE() and NONNULLVALUE() can be > documented there, along with IS, IS NULL, and IS NOT NULL (which also > don't seem to have been covered yet in Chapter 9). I don't think we should document nullvalue() and nonnullvalue(), because they are not standard. As for "not covered", IS NULL is documented in 9.2 Comparison Operators. regards, tom lane
Tom Lane wrote: >>Perhaps we can change section 9.1 from "Logical Operators" to "Logical >>Functions and Operators"? NULLVALUE() and NONNULLVALUE() can be >>documented there, along with IS, IS NULL, and IS NOT NULL (which also >>don't seem to have been covered yet in Chapter 9). > > I don't think we should document nullvalue() and nonnullvalue(), because > they are not standard. > > As for "not covered", IS NULL is documented in 9.2 Comparison Operators. Ah, it's not immediately visible so I missed that. Thanks. -- dave