
In various writings over the past 20 years, such as [3], Date has pointed out that SQL produces incorrect answers to some queries where a null value is included in a table. In a recent article in the ACM SIGMOD Record, [8], Rubinson states that "Date misinterprets the meaning of his example query" and "SQL returns the correct answer to the query posed". The purpose of this article is to show that, contrary to Rubinson's claim, Date's critique of query evaluation in the presence of null values in SQL is completely justified.
| selected citations These citations are derived from selected sources. This is an alternative to the "Influence" indicator, which also reflects the overall/total impact of an article in the research community at large, based on the underlying citation network (diachronically). | 8 | |
| popularity This indicator reflects the "current" impact/attention (the "hype") of an article in the research community at large, based on the underlying citation network. | Average | |
| influence This indicator reflects the overall/total impact of an article in the research community at large, based on the underlying citation network (diachronically). | Top 10% | |
| impulse This indicator reflects the initial momentum of an article directly after its publication, based on the underlying citation network. | Average |
