Comparison of Expressive Power of Some Query Languages for Databases
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چکیده
A version of the SQL language and a version of the stratified Datalog are considered, and it is proved that each of these languages can be translated into the other. DOI: 10.1134/S0081543811060174 A decisive role in my scientific career was played by my teacher, the outstanding Russian mathematician Anatolii Ivanovich Mal’tsev. After his decease, I faced great difficulties that I could have hardly overcome without constant support from Sergei Ivanovich Adian. I consider it a great honor to take part in this collection of scientific papers.
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تاریخ انتشار 2011