I am currently working on a homework assignment that requires a selection to occur that pulls out an element containing a specific attribute of maximum value compared to all other records. I\'ve read
There is a DISTINCT operator in SQL. However, I have an assignment in which I need to get some disti开发者_运维知识库nct values from a table, and I can only use relational algebra. Is there a way?Rela
U开发者_StackOverflow社区sing basic operators, derive the additional operator intersection. R ∩ S = ?
I\'m new to relational algebra and finding it difficult. I\'ve answered a few questions; however, they where relatively simple. Could do with help开发者_Go百科 with these though.
First time i encounter a relational algebra for databases question today, and i can\'t seem to find the answer.
I now think about write a parser to parse Logical Expressions Relational Algebra to T-Sql Codes and vice-versa! Whether there is an parser to 开发者_开发问答do this? Otherwise how can i do this? What
According to my professor in Intro. to Database Theory, th开发者_运维问答ere are NO examples in existence to show when this occasion would arise which seems a little bizarre considering its a specific
How do I represent a subquery in relation algebra? Do I 开发者_如何学运维put the new select under the previous select condition?
How do I rep开发者_Go百科resent the SQL \"not exists\" clause in relational algebra?The SQL NOT EXISTS construct can be represented in relational algebra by the antijoin ▹.
I\'m doing开发者_运维问答 my best to bend my brain around arel and the relational algebra behind it, but how to represent a SELECT DISTINCT is consistently eluding my comprehension. Can anyone explain
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