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For each attribute of a relation, there is a set of

Question: For Each Attribute Of A Relation, There Is A Set Of Permitted Values, Called The _____ Of That Attribute. A) Domain B) Relation C) Set D) Schema. This problem has been solved! See the answer. For each attribute of a relation, there is a set of permitted values, called the _____ of that attribute. a) Domai Q For each attribute of a relation, there is a set of permitted values, called the _____ of that attribute. A. Domain B. Relation C. Set D. Schema View Answer. Answer: A The values of the attribute should be present in the domain.A domain is a set of values permitted

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1. Question is ⇒ For each attribute of a relation, there is a set of permitted values, called the _____ of that attribute., Options are ⇒ (A) Relation, (B) Schema, (C) Set, (D) Domain, (E) , Leave your comments or Download question paper
2. For each attribute of a relation, there is a set of permitted values, called the ________ of that attribute. A Domain B Relation C Set D Schem
3. For each attribute of a relation, there is a set of permitted values, called the _____ of that attribute. A. Domain: B. Relation: C. Set: D. Schema: Q. Relational Algebra is a _____ query language that takes two relation as input and produces another relation as output of the query. A. Relational
4. For each attribute of a relation, there is a set of permitted values, called the. of that attribute For each attribute of a relation, there is a set of permitted values, called the _____ of that attribute. a) Domain b) Relation c) Set d) Schema. a. 6. Database _____ which is the logical design of the database, and the database _____ which is a snapshot of the data in the database at a given instant in time For each attribute of a relation, there is a set of permitted values, called the _____ of that attribute. A). Domain B). Set C). Relation D). Schema View Answer. Correct: A. 26. A domain is atomic if elements of the domain are considered to be _____ units. A). Different B). Constant C). Indivisbile D). Divisibl A primary key is an attribute or a set of attributes that uniquely identifies an instance of an entity. For example, in your entity users, you could select email as a candidate primary key. After all, emails are unique and identify a particular user. There is a problem, however, with that primary key. People can, and often do, change emails

5. For each attribute of a relation, there is a set of permitted values, called the _____ of that attribute. a) Domain b) Relation c) Set d) Schem For each attribute of a relation, there is a set of permitted values, called the _____ of that attribute. Domain Schema Relation Set. Please /register to bookmark chapters. Subjects Aptitude Basic Life Skills High School Elementary School Entrance and Placement Exams Jobs and Occupation Records are each row in the relation. Keys are the constraints in a relation. Therefore Table is the answer. Q4.For each attribute of a relation, there is a set of permitted values, called the _____ of that attribute. A. Domain; B. Relation; C. Set; D. Schema; Answer: Domain, The values of the attribute should be present in the domain ⇒ The set of permitted values for each attribute is called its : Attribute range Attribute set Group Domain ⇒ A report generator is used to : Data Entry Update files Print files on paper None ⇒ The most commonly used operation in relational algebra for projecting a set of tuple from a relation is Select Join Union Projectio

For each attribute of a relation, there is a set of permitted values, called the __ of that attribute? A. Domain B. Relation C. Set D. Schema. February 28, 2021 Mushtaq Ahmad Mohmand Computer, Database Mcqs, The Relational Model. Post navigation For each attribute of a relation, there is a set of permitted values, called the _____ of that attribute. a) Domain b) Relation c) Set d) Schema. Answer:a Explanation:The values of the attribute should be present in the domain.Domain is a set of values permitted . 6. Database _____ , which is the logical design of the database, and the database. Fields are the column of the relation or tables.Records are each row in relation.Keys are the constraints in a relation . Explanation: Column has only one set of values.Keys are constraints and row is one whole set of attributes.Entry is just a piece of data. Workspace For each attribute of a relation, there is a set of permitted values. For each attribute of a relation, there is a set of permitted values, called the _____ of that attribute. a) Domain b) Relation c) Set d) Schema Answer: a Explanation: The values of the attribute should be present in the domain. Domain is a set of values permitted. 35. Database _____ which is the logical design of the database, and the database. 1. . An Entity is a________________. Relationship model. Relational Model. Object having same Value. Object in the real world distinguishable from all other objects. D. Object in the real world distinguishable from all other objects. Explanation : For example each person in an enterprise is an entity, an entity has a set of properties, and. In relational database theory, a relation, as originally defined by E. F. Codd, is a set of tuples (d 1, d 2,..., d n), where each element d j is a member of D j, a data domain

Relation Instance C. Relation Schema Explanation : Relation schema defines the design and structure of the relation like it consists of the relation name, set of attributes. every attribute would have an associated domain The domain of the attribute is the set of permitted values (e.g. the telephone number must be seven positive integers). Formally, an attribute is a function which maps an entity set into a domain. Every entity is described by a set of (attribute, data value) pairs. There is one pair for each attribute of the entity set The attributes show a linear relationship Show Answer. c. increases with the size of the maximum frequent set d. decreases with increase in size of the maximum frequent set Show Answer. If there is a rule for each combination of attribute values, what do you called that rule set R Select one: a. Exhaustiv Mapping relationship sets (no key constraints) Students mn name email Courses code name year Takes mark Algorithm Create a table for the relationship set. Add all primary keys of the participating entity sets as elds of the table. Add a eld for each attribute of the relationship. Declare a primary key using all key elds from the entity sets attributes or participate in relationships that do not apply to the higher-level entity set. Depicted by a triangle component labeled ISA (E.g. customer is a person). Attribute inheritance - a lower-level entity set inherits all the attributes and relationship participation of the higher-level entity set to which it is linked

A primary key is an attribute or a set of attributes that uniquely identify each tuple in a relation. There is one primary key for each relation within a database. Keep in mind that the primary key should never contain NULL values. In case, one column contains Null values then it cannot be defined as the primary key But, in this case we may avoid it by associating the Start_Date attribute to either Employee or Department entity. 2. One to many relationship: In an organisation many employees can work for a department but each employee can work for only a single department. So, there is a one to many relationship between the entitie Each attribute can take only a set of permitted values. This is called the domain of that attribute. For example, we define the roll_no of the 'Student' by a numeric value. So, the permitted values are only integers and hence, 'integer' is the domain of attribute 'roll_no' For each attribute of a relation, there is a set of permitted values, called the _____ of that attribute. Domain Relation Set Schema. DBMS Objective type Questions and Answers. A directory of Objective Type Questions covering all the Computer Science subjects We say that there is a functional dependency from X to Y, The set of attributes X is called the left-hand side of the FD, and Y is called the right-hand side. X functionally determines Y in a relation schema R if, and only if, whenever two tuples of r(R) agree on their X-value each relation, and that each relation has a designated primar

Question is ⇒ For each attribute of a relation, there is a

1. - There are at least 3 attributes A, B, C in a relation and - For each value of A there is a well defined set of values for B, and a well defined set of values for C, - But the set of values for B is independent on the set of values for C • 4NF = 3NF with no multi-valued dependenc
2. Relationship Set The current value of an entity set is the set of entities that belong to it. Example: the set of all bars in our database. The value of a relationship is a relationship set, a set of tuples with one component for each related entity set
3. In the relational model, a relation scheme is defined as a set of attributes, together with an assignment rule that associates each attribute with a set of legal values that may be assigned to it. These values are called the domain of the attribute
4. Answer: (d). Both A many-to-many relationship set and A multivalued attribute of an entity set. 93. Which of the following has each related entity set has its own schema and there is an additional schema for the relationship set? a. A many-to-many relationship set. b. A multivalued attribute of an entity set. c

• Each team has many players, and each player belongs to one team. Each player has a number (unique identifier), name, DoB, start year, and shirt number that he uses. • Teams play matches, in each match there is a host team and a guest team. The match takes place in the stadium of the host team The set of permitted values for each attribute is called its : A Attribute set. B Attribute range. C Domain. International Relationship Current Affairs. NITI Aayog Current Affairs. Science & Technology Current Affairs. Sports Current Affairs. Union Budget 2021 Current Affairs. Jobs by Qualification that the given relation instance satisfies. C → B A → B AC → B b) Assume that the value of attribute C of the last record in the relation is changed from C3 to C2. Now list all the functional dependencies that this relation instance satisfies. Same as part (a). Functional dependency set is unchanged. Ques 3 A set of attributes is a key for a relation if: 1.no two distinct tuples have the same values for all key attributes, and 2.this is not true for any subset of that key. If there is more than one key for a relation (i.e., we have a set of candidate keys), one is chosen (by the designer or DBA) to be the primary key Create a relation with the following set of attributes: N (degree of relationship) Uprimary_key(E i) U {a 1a M} i=1 primary keys of each entity type participating in the relationship attributes of the relationship type (if any) exammark labmark ENROLLED name given family STUDENT studno no. of students equip subject courseno COURS

Relation. A relation, also known as a table or file , is a subset of the Cartesian product of a list of domains characterized by a name. And within a table, each row represents a group of related data values. A row, or record, is also known as a tuple. The columns in a table is a field and is also referred to as an attribute Create a relation for each entity set. It can use the same name and same set of attributes as the entity set. The key of the entity set is used as the primary key of the relation. For example, Student(ssn, last, first, streetaddress, city, state, country, zip) Course(dept, number, title, description, credits) Section(crn, days, time, room

• Entity set vs. attributes • Has more data à entity set • Is the data à attribute • Entity set vs. relationship set • Entity set à nouns (students, faculty, loads, ) • Relationship à possession verbs (teaches, advises, owns, works for, ) • Binary vs. n-ary relationship sets • Specialization / generalizatio Explain why each of these properties may indicate a bad relational-database design. Answer: Repetition of information is a condition in a relational database where the values of one attribute are determined by the values of another attribute in the same relation, and both values are repeated throughout the relation

DBMS MCQs Test 10 DBMS Online Tests - Studytonigh

• on. The attribute values that describe each entity become a major part of the data stored in the database. For each attribute there is a set of permitted values called the ' domain ' or ' value set' of that attribute. The domain of attribute student name might be the set of all text strings of a certain length. There are 3 main attribute types as discussed below: Simple and composite.
• ant is an attribute or combination of attributes that uniquely identifies a row in a relation. False _____ entities are entities that cannot exist except with an identifying relationship with a regular entity type
• relation, attributes of the relation must include: - Keys for each participating entity set (as foreign keys). - This set of attributes forms a superkeyfor the relation. - All descriptive attributes. CREATE TABLE Works_In(ssn CHAR(1), did INTEGER, since DATE, PRIMARY KEY (ssn, did), FOREIGN KEY (ssn) REFERENCES Employees, FOREIGN KEY (did

DBI202_sanfoundry Flashcards Quizle

1. imal attribute (s) that can identify each tuple uniquely in the given relation is called as a candidate key. A
2. 3. A set of v alues of one t yp e: either atomic or a \struct t yp e. F or example, the t yp e of an attribute in suc h a mo del could b e a set of pairs, eac h pair consisting of an in teger and a string. kind of en tit y, and the set of studios is a third en y set that will app ear in our examples. 2 2.1.2 A ttributes En tit y sets ha v e.
3. An additional constraint is needed to ensure that each nickname refers to at most one flag. A simple attribute uniqueness constraint (e.g., {U1}) is not enough, since the nicknames attribute is set valued. Not only must each nicknames set be unique for each flag, but each element in each set must be unique (the second condition implies the former)
4. The 'Current relation' box above 'Attribute' box displays the base relation (table) name and the current working relation (which are initially the same) - weather, the number of instances - 14 and the number of attributes - 5. During the scan of the data, WEKA computes some basic statistics on each attribute. Th
5. The member of a weak entity set called as a subordinate entity set. Primary Key is one of its attributes which helps to identify its member. In a weak entity set, it is a combination of primary key and partial key of the strong entity set. In the ER diagram the relationship between two strong entity set shown by using a diamond symbol
6. Identifier of relationship type • Let K be a set of identifiers of some entity types participating in a relationship type R. K is called a . key . of the relationship type R if there is an 1:1mapping from R into the Cartesian Product of the associated value sets of K and no proper subset of K has such property

DBMS MCQ Questions With Answers Set

To normalize into 2NF, we remove the attributes that are functionally dependent on part of the key (A or B) from R and place them in separate relations R1 and R2, along with the part of the key they depend on (A or B), which are copied into each of these relations but also remains in the original relation, which we call R3 below Identify and define the primary key attributes for each entity; Validate primary keys and relationships; Migrate the primary keys to establish foreign keys; Define Primary Key Attributes: Attributes are data items that describe an entity. An attribute instance is a single value of an attribute for an instance of an entity. For example, Name and. Clicking through each attribute in the list of Attributes and reviewing the plots, we can see that there is no such easy separation of the classes. We can quickly get an overview of the distribution of all attributes in the dataset and the breakdown of distributions by class by clicking the Visualize All button above the univariate plot A relation is in third normal form, if there is . no transitive dependency for non-prime attributes as well as it is in second normal form. A relation is in 3NF if at least one of the following condition holds in every non-trivial function dependency X -> Y: X is a super key. Y is a prime attribute (each element of Y is part of some candidate. If any attribute's or set of attributes' closure gives all the attributes of the relation, then we would say that attribute/set of attributes as the key for that relation. To simplify this task or to avoid wasting time on finding closure of all attributes, let us do find the closure for left hand side (LHS) attributes of the given.

The projection eliminates all attributes of the input relation but those mentioned in the projection list. The projection method defines a relation that contains a vertical subset of Relation. This helps to extract the values of specified attributes to eliminates duplicate values. (pi) symbol is used to choose attributes from a relation The attribute evaluator is the technique by which each attribute in your dataset (also called a column or feature) is evaluated in the context of the output variable (e.g. the class). The search method is the technique by which to try or navigate different combinations of attributes in the dataset in order to arrive on a short list of chosen. It is an attribute or set of attributes that must have values from Primary Key of the strong Entity on which a weak Entity depends on. It is represented by underlining the attribute name with a dotted line. Whenever there is some relationship between two entities there must be some common attributes between them Chapter 11 Functional Dependencies Adrienne Watt. A functional dependency (FD) is a relationship between two attributes, typically between the PK and other non-key attributes within a table.For any relation R, attribute Y is functionally dependent on attribute X (usually the PK), if for every valid instance of X, that value of X uniquely determines the value of Y

Database Design: Entities, Attributes, and Relationships

1. Non-key attribute.An attribute A in relation R is said to be a non-key attribute if it is not a subkey,i.e., A is not a component of anycandidate key K ofR. Second normal form.Arelation R is said to be in second normal formif R is in 1NF and every non-key attribute isfullydependent on each candidate key K ofR.I
2. There is one data line for each relation in the graph. Each data line is described by its origin and destination, and value. Here. since there are two relations, KNOKI and KNOKM there are two values -- each of which happens, in our example, to be binary (but they could be valued)
3. imal cover for a set of FDs F Step 1: Let G be the set of FDs obtained from F by decomposing the right hand sides of each FD to a single attribute. Step 2: Remove all redundant attributes from the left hand sides of.
4. 8.1.9 The attributes of relationship teaches in teacher teaches course should be. members of an entity set or a relationship set 8.2.9 Rows of a relation are called (a) tuples (b) a relation row there are no composite attributes in the relation (c) there are only a few composite attributes (d) all attributes are of uniform type.

A) Since the there is a relationship means our model is not good B) Since the there is a relationship means our model is good C) Can't say D) None of these Ans Solution: (A) There should not be any relationship between predicted values and residuals Each attribute has a name, and is associated with an entity and a domain of legal values. However, the information about attribute domain is not presented on the ERD. In the entity relationship diagram, shown in Figure 8.2, each attribute is represented by an oval with a name inside - A relation may be thought of as a set of rows. - Each row represents a fact that corresponds to a real-world entity or relationship. - Each row has a value of an item or set of items that uniquely identifies that row in the table. - Each column typically is called by its column name or column header or attribute name The music database stores details of a personal music library, and could be used to manage your MP3, CD, or vinyl collection. Because this database is for a personal collection, it's relatively simple and stores only the relationships between artists, albums, and tracks. It ignores the requirements of many music genres, making it most useful for storing popular music and less useful for. The relation scheme of such junction tables are also part of the database scheme diagram. The scheme of a junction table (sometimes also called a join table or linking table) will contain two sets of FK attributes, one for each side of the association. If there is no association class, then the scheme only contains these two FKs

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One way is to find F+ (the closure of the set of FDs). But it can be very large. What we can do instead is use the notion of a closure of an attribute set. That is the set of all attributes determined by an attribute set. (From the determined attributes we know all the FDs that hold with that determinant.) There is an algorithm for finding it Now we read about each key. Candidate Key A Candidate key is an attribute or set of attributes that uniquely identifies a record. Among the set of candidate, one candidate key is chosen as Primary Key. So a table can have multiple candidate key but each table can have maximum one primary key. Example: Possible Candidate Keys in Branch_Info table Strictly speaking, a foreign key is a set of attributes, but when that set contains only one attribute, then that attribute itself is often informally called a foreign key. The schema of this question has the following five foreign keys: 1. the attribute Cust# of relation ORDER that references relation CUSTOMER, 2. the attribute Order# of relation

For Each Attribute Of A Relation, There Is A Set Of

- Attributes are single-value: each attribute represents a property of the entity, e.g., for each entity m belonging to an entity set Movies, m can have only one title. - Attributes different than keys can have null value (also called unknown): the length of a movie can be missing - Many-one relationship imposes a single-valu Suppose you are given a relation R with four attributes ABCD.For each of the following sets of FDs, assuming those are the only dependencies that hold for R, do the. Q.31 If the closure of an attribute set is the entire relation then the attribute set is a There are two types of ordered indices : dense and sparse. In dense index, and index record appears only for some of the search-key in the files as shown below. , attribute, role and relationship between the entities,.

Types of DBMS: Videos, Examples and Practice Question

• equivalence relation and the equivalence classes of R are the sets of F. Pf: Since F is a partition, for each x in S there is one (and only one) set of F which contains x. Thus, x R x for each x in S (R is reflexive) If there is a set containing x and y then x R y and y R x both hold. (R is symmetric)
• A functional dependency X → Y in a relation R is a transitive dependency if there is a set of attributes Z that is not a subset of any key of R, and both X → Z and Z → Y hold. In this case we must split this relation into two new relations and a join between both will recover the original relation
• The result will be a relation with the attributes namn There is no common set of courses that should be tested for each person. The formulation in SQL will often be easier than that using division; to express the example query it is enough to create.
• 3 will yield a relation of at most 1000 tuples because E is a key for r 3. Therefore the ﬁnal relation will have at most 1000 tuples. • An efﬁcient strategy for computing this join would be to create an index on attribute C for relationr 2 and on E forr 3. Then for each tuple in r 1, we do the following: a. Use the index for
• The Entity-Relationship Model • Basic Concepts: - Attributes: • For each attribute, there is a set of permitted values, called the domain, or value set, of that attribute. The domain of attribute customer-name might be the set of all text strings of a certain length
• The attribute contact_person_type_id is not a part of the alternate key. If so, we could have multiple relations for the same contact person and the same student (using different types of relationship), and that makes no sense in real life situations. The model presented in this article should be able to cover most common needs
• A function is a relation which describes that there should be only one output for each input (or) we can say that a special kind of relation (a set of ordered pairs), which follows a rule i.e every X-value should be associated with only one y-value is called a function

300+ TOP RDBMS Multiple Choice Questions and Answers 202

• 1) Semantics: meaning of the attributes in a tuple - how they relate to each other ex: TOY database - the meaning of each relation schema is pretty straightforward look at the TOY relation: TOY_NUM is a key (primary key) NAME - the name of the toy MAN_ID - a foreign key representing an implicit relationship between the TOY db and the.
• ate the Sell relationship set. 3. The date information can no longer be modeled as an attribute of Prescription. We have to create a new entity set called Prescription date and make Prescription a 4-way relationship set that involves this additional entity set
• THE ENTITY-RELATIONSHIP MODEL Exercise 2.1 Explain the following terms brieﬂy: attribute, domain, entity, relation-ship, entity set, relationship set, one-to-many relationship, many-to-many relationship, participation constraint, overlap constraint, covering constraint, weak entity set, aggre-gation,androle indicator
• imal superkey. 3. Primary Key (PK) - Candidate Key selected to uniquely identify all other attribute values in any given entity
• A relation is an equivalence iff it is reﬂexive, symmetric and transitive. Partial Order Deﬁnition 4.2. A relation, R, on a set, A, is a partial order providing there is a function, g, from A to some collection of sets such that a 1 Ra 2 iff g(a 1) ⊂ g(a 2), (3) for all a 1 = a 2 ∈ A. Theorem

RDBMS Questions and Answers - All India Exam

Each relation has primary keys underlined. select the dept name attribute from the instructor relation, there are several cases In general, a row in a table represents a relationship among a set of values. Since a table is a collection of such relationships, there is a close correspondence. An attribute is a piece of information about the entity. For example, the title, author, and ISBN are all attributes of a book entity. In terms of a research data set, each variable in the data set corresponds to an attribute. The task of designing a database to store the data set comes down to assigning each variable to a particular entity For binary relationship with cardinality ration m : n , separate and individual tables will be drawn for each entity set and relationship. For binary relationship with cardinality ratio either m : 1 or 1 : n , always remember many side will consume the relationship i.e. a combined table will be drawn for many side entity set and. For M:N relationship types some attribute are determined by the combination of the participating entities, not by a single enity. Such attribute must be specified as the relationship attributes Ex: No.of hours an employee works on is department is determent is determined by the EMPLOYEE-PROJECT combination

[MCQs] Database Management Systems - LM

• Attribute values are chosen from a domain of legal values; for example, we could specify that a customer's given names and surname attributes can each be a string of up to 100 characters, while a telephone number can be a string of up to 40 characters. Similarly, a product price could be a positive rational number
• DBMS Chapter 4 ������1. The set of possible values for an attribute is a ____. a. set b. domain c. key d. range b. domain 2. In an ER diagram identifiers are indicated b
• For each . multi-valued attribute A • Create a new relation R that includes an attribute corresponding to A plus the primary key attribute K (as a foreign key in R) of the relation that represents the entity type or relationship type that has A as an attribute. • The primary key of R is the combination of A and K. If a multi-valued attribute is
• ent areas of the era finds its place in the curriculum of many universities or institutes, among which is Savitribai Phule Pune University(SPPU).. Machine Learning subject, having subject no.:- 410250, the first compulsory subject of 8 th semester and has 3 credits in the course, according to the new credit system. . This subject is the first compulsory.

Entity Relationship Model MCQs - Database Management

Conventions. Manual configuration. Other relationship patterns. Additional resources. A relationship defines how two entities relate to each other. In a relational database, this is represented by a foreign key constraint. Note. Most of the samples in this article use a one-to-many relationship to demonstrate concepts This rule defines that all the attributes in a relation must have atomic domains. The values in an atomic domain are indivisible units. We re-arrange the relation (table) as below, to convert it to First Normal Form. Each attribute must contain only a single value from its pre-defined domain. Second Normal For

Relation (database) - Wikipedi

There's a one-to-one relationship between our two tables because there are no repeating values in the combined table's ProjName column. The ProjName column is unique, because each value occurs only once; therefore, the rows from the two tables can be combined directly without any duplication.. But, let's say you know the data will change the next time you refresh it Relationship Set borrower Database System Concepts 2.8 ©Silberschatz, Korth and Sudarshan Relationship Sets (Cont.)! An attribute can also be property of a relationship set.! For instance, the depositor relationship set between entity sets customer and account may have the attribute access-dat XTREAM COMPUTERS WORLD : MCQ ON Relational Database and

A composite attribute is one that can be subdivided to yield attributes for each of its components. If the E-R diagram contains the attribute names for each of its entities, a composite key is indicated in the E R diagram by the fact that more than one attribute name is underlined to indicate its participation in the primary key qualify the attribute name with the relation name and separate them with a dot(.). This is done by prefixing the relation name to the attribute name. Ambiguity also arises in the case of queries that refer to the same relation twice as in the following QUERY: For each employee, retrieve the employee's first and last name and th Entities are described by a set of properties called attributes. Each entity must have the values for its attributes which is uniquely identifiable from other entities in a particular entity set. Following are the entities and its attributes for the Late Travel (LT). Below are the Entities (customer, employee and booking) and there attributes You can use a relational schema to describe self-referencing relationships.For instance, two employees who are married to one another could feature the Spouse foreign key. For both of these employee's foreign keys, the reference will be to the other employee's Employee ID, which is the primary key of each employee's respective table.. This also works in relationship schema with a 1:N.

Structure of Relational Databases MCQs - Database

Each non-key attribute must be fully functionally dependent on the entire primary key, and not on any other non-key attribute - no transitive dependencies exist among attributes. When your database is in 3NF you can analyze each table independently of all others in the database, and then deduce a normal form for that table In statistics, dependence or association is any statistical relationship, whether causal or not, between two random variables or bivariate data. Correlation is any of a broad class of statistica Entities and Entity Sets - Computing Scienc

1. Each consumer can buy many products, and each product can be bought by many consumers. The detailed Crow's Foot Relationship symbols can be found here. Crow's Foot Relationship Symbols. Many to many relationships are difficult to represent. We need to decompose a many to many (M:M) relationship into two one-to-many (1:M) relationships
2. Attribute-Relation File Format (ARFF) November 1st, 2008 Each attribute in the data set has its own @attribute statement which uniquely defines the name of that attribute and it's data type. The order the attributes are declared indicates the column position in the data section of the file. There is a known problem saving SparseInstance.
3. There can be more than one key, we pick one to be the primary key. Turn each entity set into a relation with the same set of attributes. For each entity set involved in relationship R, we take its key attribute and key attributes of its entities as part of the schema of the relation for R
4. Each book has title, author, publisher, date-of-publication, ISBN number and a set of keywords. Each student has SSN, first name, last name, address, telephone number. A student can borrow a book for up to two weeks, so it is necessary to keep track of the date-of-borrow
5. The schema for each relation. The domain of values associated with each attribute. Integrity constraints (e.g. NOT NULL) Other information such as The set of indices to be maintained for each relations. Security and authorization information for each relation. The physical storage structure of each relation on disk
6. Rule: 2NF: Each non-prime-attributes has to be fully functionally dependent from each candidate key. But: The non-prime-attribute F is not fully functionally dependent from the candidate-key {B, C} because e.g. {B} also identifies the attribute. Thus it is in 1NF. The key here is to divide into primes and non-primes 