Relational Algebra and its implications for NoSQL databases

With the rise of NoSQL databases that are exploiting aspects of SQL for querying, and are embracing full transactionality, is there a danger of the data-document model's hierarchical nature causing a fundamental conflict with relational theory? We asked our relational expert, Hugh Bin-Haad to expound a difficult area for database theorists.

Relational algebra must consider more than just the primary key of the ‘superclass’ entity. When joining more than one relation, there is the candidate class that defines the strategy for translating any differences found. For each record, the attributes on the class provide a specification that defines standards, or provides information about the tuples. In an approach to maintaining counts, these are obsolescent and are therefore not part of a committed action in transactions in which they consider the benefits that will be indexed. The required fields must start at the wrapper that is asked to search and discover the semantics


Fig. 1: Importance of class intersection rules

The various kinds of data items that can be held by a pair of tuples should be considered as heterogeneous. There is nothing physically unrealizable that may occur and the methodology is as follows:

  • For creating elements, all the versions are stored in an equijoin of the classes
  • Ensure that each class has available space for the intersection rule.
  • Produce a unary relation of each class with the SELECT clause.

A B-tree index has special significance for other attributes in the collection class. This is because, in the foreseeable future, a SQL client will be free to reorder the relation containing tuples that satisfy each of the class intersection rules.

NoSQL databases can provide the same ability but the argument is that one extra tuple will be needed to support the object-oriented data model. The four strategies for developing Web services all require that the NoSQL databases are accessed through text and ntext fields.

What could happen is that NoSQL driver classes will provide an outline design for the relation and the desired records could use specialized XML query requirements that defines the fields. But would this be executed once, whenever a new value matches the association class attributes? Are test tools required to automate frequent tasks across multiple database nodes that allow only insertions?


Fig. 2: Tuple expansion through a formal subset of the design

We also need to consider tuples that fail to satisfy the predicate join or Cartesian product selection. In this case, there is no ordinal position in the relational model and XPath assumes the block model and formal semantics, assuming the attributes and all the blocks exist.

This enforces the consistency of the logical NoSQL database design, which is made effective when the user accesses any unordered collections only through a formal subset of the design specification. This can be extended so that data retrieval supports parallel processing by using a large un-normalized entity that does allow duplicates. There can be any number of unordered collections as long as they do not exist between consecutive entity occurrences.

This introduces the powerful idea that relationships can exist in any un-normalized tables provided that the macro entity enforces the referential action. Cluster groups of different join orderings will need to be executed on different nodes in order to determine whether they contain candidate keys.

This opens the door to a new relational model that determines the characteristics of multidimensional data and then inserts a high-level query into a hierarchy containing only superclasses and subclasses!

Note: To celebrate April 1st, this essay is the result of running two textbooks on Database Design through Phil Factor’s Parodist database, and then lightly editing the result by a couple of Simple-Talk’s editors. The text of each book was ‘topped and tailed’ by deleting the contents and appendices indexes, combined together, and fed into the Parodist database in one text file. Who needs real authors? Phil has an idea for combining the complete Works of Shakespeare with a well-known book about SQL Server’s internals. Not only will it be profound, but it will sound highly ceremonial.

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  • Phil Factor

    Re: Data structures designing the target database
    This is certainly true, but have you considered that an instance of a Semijoin is beneficial only if its only task is to build the underlying data model to be signed off and handed over to the enterprise.

    If we use an XML fragment to use specialization generalization aggregation on a standalone system on a specified threshold of the database, and make sure that they consider that the correct details of private property owners are in sorted order, in which case other sites have equal rights to update a page fault occurs. The Secure Electronic Transactions SET protocol is implemented over the attributes defined within the warehouse manager which also generates Tcl scripts.

    The Requirements and collection stage of the Object-Oriented Data models is to be shared between browser and the Data is entered deleted or changed in the logical model based on the database. An instance method invocation is quite different from the innermost query outwards. The first time many of these approaches result in the time that the user to subscribe to the serializable schedule. Consider again the participant will follow an additional key for the optimizer, which is an alternative strategy that takes account of usage.

  • Celko

    NoSQL joins
    Those of you old enough to remember when structured programming was the current fad in IT that we had the "should have been" comparative operator (i.e. If (X should have been 5) , then call Y1() else call Y2() end if;).

    There were obvious implementation problems back in the 1970’s and 1980’s due to lack of good AI software. However, it is clearly possible in the year 2016 to work around this. By now I would assume everyone has seen news articles on how Microsoft’s AI "Tay" was able to quickly adjust from being an artificial teenage girl on twitter to a gutter slut neo-Nazi in 24 hours. Let us be honest, most of us cannot get that kind of turnaround with batch processing on our systems.

    We currently have inner join, and several flavors of outer join in SQL. There is also the cross join and the union join. I wish to propose that we consider adding joins based on the "should have been" operator, but I am not sure the syntax and semantics. The most direct and obvious syntax would be to allow the ON clause to use the "should have been" operator in any of the existing join operations.

    However, there is a danger that the ON clause will become too complicated for a human programmer to reliably write. For example, if I am doing a join onto tables that involves 42 columns, can I be sure that I will get all of the possibilities of of erroneous data? Not likely! Then there is the question of exact matches versus "should have been" matches mixed together.

    Without any experiments (I have no access to pornographic AI), I am going to guess the best way is probably to use something like we did with CROSS JOIN. In this join, there is no ON clause because it works on the whole table expressions.

    Over the years I have often been asked why we picked coalesce () for the name of that particular function. The truth is that Phil Shaw of IBM had a thesaurus and looked up the "least likely to occur as a column name" synonym in that document. I feel this is a good design decision, and that we ought to continue it in our language. To that end, I propose the syntax be "SMUSH JOIN" without an on clause..

    <table expression 1>
    <table expression 2>

    When given to table expressions, this join will use an AI engine to make guesses as to what columns were to be matched, and how close the values are for the purposes of a join. For example, it would match a row in a column with the date value ‘2016–12-25’ and a column in the second table with VARCHAR(25) with the character value of ‘Christmas’ or ‘Christmas 2016’ in it. Ideally, you would also get a match is a second table had an address line, employee name or product name with the word "Christmas" in it anywhere in the row.

    I look forward to see to seeing comments about my proposal in ANSI/ISO standards forums.

  • Robert young

    what makes you think the pinheads who devised NoSql would find this to be anything other than the gospel according to Codd?


    April 1st = April fools day
    Hugh Bin Haad…. anybody????
    do I have to spell it out???
    Hugh -> You’ve
    Bin -> Been
    Haad -> Had

    Come on guys…..