Baze Podataka Drugi Kolokvijum

The correct answer is DISTINCT. When using the SELECT query, the DISTINCT keyword is used to eliminate duplicate records from the result set. It ensures that only unique values are returned in the table. This means that if there are multiple rows with the same values, only one of them will be included in the result set.

The answer 1:M means that one worker works in one department, and one department can have multiple workers. This indicates a one-to-many relationship between the workers and the departments. Each worker is assigned to only one department, but a department can have multiple workers.

The given answer states that "RAČUN je čvrst objekat a STAVKA slab" which translates to "RAČUN is a strong object and STAVKA is weak". This means that the object "RAČUN" is considered to have a strong importance or significance, while the object "STAVKA" is considered to have a weaker importance or significance.

The answer (1,1) indicates that the attribute should have a cardinality of one-to-one in order to be a unique attribute of an entity. This means that each entity instance can have only one value for this attribute and each value can be associated with only one entity instance.

The correct answer is "CREATE TABLE ODELJENJE (BROD integer, IMEOD Text(20), MESTO Text(20));". This is the correct SQL code for creating a table named "ODELJENJE" with three columns: "BROD" of type integer, "IMEOD" of type Text with a maximum length of 20 characters, and "MESTO" of type Text with a maximum length of 20 characters. The other options provided are not valid SQL syntax for creating a table.

The correct answer is "skup dozvoljenih vrednosti koje neki atribut može da uzeti" which translates to "a set of allowed values that an attribute can take." This explanation aligns with the concept of a domain of an attribute, which refers to the range of valid values that can be assigned to that attribute.

A digital image of a real-world object that is relevant to an information system is referred to as a model-object. This term suggests that the image represents a specific object or entity in the real world and is used as a model or representation within the information system. This could be a visual representation of a physical object or a digital representation of a concept or idea. The term "model-object" implies that the image is more than just a data point or attribute, but rather a comprehensive representation of something meaningful within the information system.

The correct answer is the first option: SELECT ime FROM tab1 WHERE ime LIKE "%a%b%" OR ime LIKE "%b%a%". This query uses the LIKE operator with wildcard characters (%) to search for names that contain both "a" and "b" in any order. The OR operator allows for either "a" followed by "b" or "b" followed by "a".

The correct answer is "Veze tipa M:N" because the network model allows for many-to-many relationships between entities. In the network model, entities are connected through sets of relationships, and each entity can be connected to multiple entities through multiple relationships. This allows for more flexibility in representing complex data relationships compared to the hierarchical model, which only allows for one-to-many relationships.

The correct answer is "broj n-torki jedne tabele koji su u relaciji sa jednom n-torkom druge tabele" because cardinality refers to the number of tuples in one table that are related to one tuple in another table. It represents the relationship between tables in a relational database. The other options are not related to the concept of cardinality.

The given correct answer is "normalizacija." Normalizacija is a process of decomposing a table in a relational database to eliminate redundancy and achieve a well-structured relational model. It involves breaking down a table into smaller tables and establishing relationships between them. This helps in improving data integrity, reducing data duplication, and enhancing overall database performance.

The correct answer is "virtuelna tabela sa imenom." This means that the "Pogled" (view) is a virtual table with a name.

When translating an E-R model, binary relationships of type 1:1 and 1:N are expressed using foreign keys, while relationships of type M:N are expressed using a junction table. This means that for 1:1 and 1:N relationships, the primary key of one entity is used as a foreign key in the other entity, establishing the relationship between them. On the other hand, for M:N relationships, a separate table is created to represent the relationship, with foreign keys referencing the primary keys of the two entities involved.

The given SQL query is selecting the columns "ime" and "imeod" from the tables "radnik" and "odeljenje" respectively. It is using a join condition where the "brod" column of the "radnik" table is equal to the "brod" column of the "odeljenje" table, and the "ime" column of the "radnik" table starts with the letter "A". The query is performing a selection operation on the entire dataset, which contains 100,000 records. Therefore, the answer is "100000 zapisa".

The correct answer is EXISTS. This is because the EXISTS clause is used to check for the existence of at least one tuple in the result of a query. It is commonly used in conjunction with a subquery to determine if a certain condition is met. If the subquery returns any rows, the EXISTS clause evaluates to true, otherwise it evaluates to false.

Anomalije pri upisu, brisanju i izmeni podataka javljaju se kao posledica nekontrolisane redundanse. This means that the anomalies in data entry, deletion, and modification occur due to uncontrolled redundancies. Redundancy refers to the unnecessary repetition of data in a database, which can lead to inconsistencies and anomalies. If the data is not properly controlled and managed, these redundancies can cause issues in data operations.

A čvrst objekat is an entity that can be fully defined by a primary key and a set of attributes. This means that the primary key uniquely identifies the entity, and the attributes provide additional information about the entity. In contrast, a vezni objekat is an object that has all the properties of an object but is not fully defined by a primary key and attributes. A slab objekat can either be identifikaciono zavistan (identification-dependent) or egzistencijalno zavistan (existentially-dependent) on a čvrst objekat, meaning its existence or identity is dependent on the čvrst objekat.

The correct answer is insert, select, delete, update. These are the basic data manipulation statements in SQL. "Insert" is used to add new records to a table, "select" is used to retrieve data from a table, "delete" is used to remove records from a table, and "update" is used to modify existing records in a table. The other options either include additional statements that are not part of data manipulation (such as "grant" and "revoke") or are incorrect combinations of statements.

Indexes allow for direct access to data in a table through attributes that are indexed. This means that instead of having to search through the entire table sequentially, the index allows for quick and efficient retrieval of specific data based on the indexed attribute. This is different from accessing data solely through the primary key or using sequential access.

The primary key is a unique identifier for each record in a database table. It ensures that each record has a unique value and cannot be duplicated. The primary key is also immutable, meaning it cannot be changed once it is assigned to a record. Lastly, the primary key must be available for retrieval and reference in order to uniquely identify each record. Therefore, the correct answer is "jedinstvenost, nepromenljivost i raspoloživost" which translates to "uniqueness, immutability, and availability" in English.

The given answer suggests that if every non-key attribute in a relation is functionally dependent on the primary key, then the relation is in the second normal form. The second normal form (2NF) requires that the relation is in 1NF and there should be no partial dependencies, meaning that every non-key attribute should depend on the entire primary key. Therefore, the given answer is correct in stating that the relation is in the second normal form.

The given correct answer is "binarne veze tipa 1:N" because it states that there is a one-to-many relationship between the tables NASTAVNIK and PREDMET, indicating that one teacher can teach multiple subjects. This means that each record in the NASTAVNIK table can be associated with multiple records in the PREDMET table, but each record in the PREDMET table can only be associated with one record in the NASTAVNIK table.

The correct answer is "doment." In the context of the given question, "doment" refers to the set of possible values that a specific attribute can have in a particular case. It is a term commonly used in the field of data modeling and database design to describe the range of values that an attribute can take on. "Atribut" refers to an attribute, "relacija" refers to a relation, and "entitet" refers to an entity, which are not directly related to the concept of a set of possible values.

The Model-View-Controller (MVC) design pattern is commonly used in software development, particularly in the design of databases. The Model objekti-veze (MOV) is specifically used in the design of databases. It helps in organizing the data and defining the relationships between different entities in the database. By using the MOV model, developers can create a clear and structured database design that can efficiently store and retrieve data. Therefore, the correct answer is "projektovanja baza podataka" (designing databases).

The correct answer is "create view, create index, create table". These are all examples of data definition statements in SQL. "Create view" is used to create a virtual table based on the result of a query, "create index" is used to create an index on a table to improve query performance, and "create table" is used to create a new table in a database.

The correct answer is the first option because it follows the correct syntax for a SELECT query. It selects the specified attributes from the specified relations, applies the specified conditions, groups the results by the specified attribute 2, applies additional conditions using the HAVING clause, and finally orders the results by the specified attribute 3.

The correct answer is "jedinstvenost i minimalnost" because for an attribute to be a candidate for a primary key, it must be unique (jedinstvenost) and it should not contain any unnecessary attributes (minimalnost). This means that the attribute should uniquely identify each record in the table and there should not be any redundant information in the primary key.

The correct answer is 4,2,1,3. The question asks for the order in which the models appeared from the first generation to the fourth. The relational model (1) was the first to appear, followed by the hierarchical and network models (2), then the object-oriented model (3), and finally the model based on programming languages (4).

The given answer "atomarni podatak" is correct because in a relation, the value of the primary key and the attribute name uniquely identify an atomic data. An atomic data refers to a single, indivisible value that cannot be further divided. Therefore, the combination of the primary key value and the attribute name in a relation ensures the uniqueness and identification of an atomic data.

The correct answer is "selekcija, projekcija i spajanje". These are the operators suitable for querying in a database. "Selekcija" refers to selecting specific rows from a table based on certain conditions. "Projekcija" refers to selecting specific columns from a table. "Spajanje" refers to combining data from multiple tables based on a common attribute. These operators are fundamental for retrieving specific information from a database.

The correct answer is "i referencijalni integritet i integritet entiteta u bazi podataka" because according to Codd, the rules of database integrity are defined in both the referential integrity and entity integrity in the database. This means that the database must maintain the consistency and accuracy of the data by enforcing rules such as primary key constraints, foreign key constraints, and domain constraints.

The correct answer is "skup svih vrednosti elementarnih obeležja koje se odnose na jedan objekat" because it accurately defines the term "zapis ili logički slog" as a set of all values of elementary characteristics related to an object. This definition implies that a "zapis ili logički slog" represents the data or information associated with an object. The other options, such as "skup zapisa koji odgovaraju jednom prostoru objekta" (set of records corresponding to a space of an object) or "biblioteka datoteka" (file library), do not accurately describe the concept of "zapis ili logički slog."

The correct answer is a list of different types of entities. It includes real objects, abstract concepts, events, and associations. These are all categories or classifications of entities that can exist in various contexts or domains.

The correct answer is "unarne veze 1:1" because the table GRAĐANIN has two attributes, matbr and matbr2, which represent the identification numbers of a person and their spouse respectively. In a 1:1 unary relationship, each record in the table is uniquely linked to another record in the same table. In this case, each person's identification number (matbr) is linked to the identification number (matbr2) of their spouse, creating a one-to-one relationship between the records in the GRAĐANIN table.

The correct answer is GRANT. GRANT is a command in SQL that is used to grant privileges or permissions to a user or a group of users. It allows the user to perform certain actions or access specific data in a database. In contrast, ALTER TABLE is used to modify the structure of a table, and DELETE is used to delete rows from a table. Therefore, GRANT is the only command that belongs to the category of control functions.

The correct answer is ALTER TABLE. This command is used to modify the structure of an existing table in a database, such as adding or deleting columns, modifying data types, or changing constraints. It is a data definition language (DDL) statement that allows users to define and alter the structure of tables to store and manipulate data. DELETE is used to remove rows from a table, while GRANT is used to grant privileges to users in a database.

The correct answer is "ALTER TABLE RADNIK ADD CONSTRIT PK_RADNIK PRIMARY KEY(IDBR)". This query adds a primary key constraint named "PK_RADNIK" to the table "RADNIK" on the column "IDBR". This ensures that the "IDBR" column will have unique values and will be used as the primary key for the table. The other options either do not specify the primary key constraint or have incorrect syntax.

The correct answer states that the set of values of the foreign key of relation R1 must be a subset of the set of values of the primary key of relation R2, without requiring that R1 and R2 be different. This means that every value in the foreign key of R1 must exist in the primary key of R2, but R1 and R2 can refer to the same relation. This ensures referential integrity, as it guarantees that every foreign key value in R1 has a corresponding primary key value in R2.

The correct answer states that the SELECT clause corresponds to the projection operator, the WHERE clause corresponds to the selection operator, and the FROM clause corresponds to the join operator. This means that the SELECT clause is used to specify the columns to be included in the result set, the WHERE clause is used to filter the rows based on certain conditions, and the FROM clause is used to specify the tables to be joined in the query.

Objects that depend on another object for identification have a complex primary key. This means that their primary key is composed of multiple attributes or fields, rather than just a single attribute. This allows for a more precise and unique identification of these objects, as the combination of multiple attributes ensures that no two objects will have the same primary key.

The correct answer is "unija, presek i razlika." This answer is correct because "unija" refers to the union operation in set theory, which combines two sets and returns a new set containing all the elements from both sets without repetition. "Presek" refers to the intersection operation, which returns a new set containing only the elements that are common to both sets. "Razlika" refers to the difference operation, which returns a new set containing only the elements that are in the first set but not in the second set. Therefore, all three operations mentioned in the answer are suitable for updating sets.

The correct answer is that one object can have multiple attributes. This means that an object can possess or be associated with multiple characteristics or properties. It is not necessary for attributes to have names, but they must have values. This statement is true because in object-oriented programming, an object is typically defined by its attributes, which describe the object's state or characteristics. Multiple attributes can be used to fully describe an object and differentiate it from other objects.

When translating an E-R model into a relational form, all objects become relations, and each relationship can, but does not have to, become a relation. This means that all entities in the E-R model will be represented as tables in the relational form, while relationships may or may not be represented as separate tables depending on the situation.

The correct answer is "grant, revoke". Grant and revoke are commands in the Data Control Language (DCL) that are used to manage permissions and privileges in a database. These commands allow users to grant or revoke specific privileges on database objects to other users or roles. They are essential for controlling access and ensuring data security in a database system. The other options mentioned in the question are not part of the DCL, but rather belong to other categories such as Data Definition Language (DDL) or Data Manipulation Language (DML).

The correct answer is DELETE because it is a command used to remove or delete data from a database. It is commonly used to delete specific records or entire tables from a database. The other options, GRANT and ALTER TABLE, are not specifically related to data manipulation but rather involve granting permissions and modifying the structure of database tables respectively.

The given correct answer states that if the set of values of the foreign key in relation R1 is a superset of the set of values of the primary key in relation R2 (where R1 and R2 can be the same relation), the referential integrity rule is violated, but it cannot be determined if the entity integrity rule is violated. In other words, the foreign key constraint is not satisfied, but it is uncertain if the primary key constraint is also violated.

The given correct answer states that a relation is in the third normal form if the non-key attributes in the table are neither functionally nor transitively dependent on the key attributes. This means that the non-key attributes should not be determined by any combination of key attributes or by any other non-key attributes. In other words, the non-key attributes should only depend on the key attributes directly. This condition ensures that there are no redundant dependencies in the table, leading to a more efficient and organized database design.

The correct answer states that for a table to be in a relation, all rows must be unique, all columns must have different names, and the order of columns and rows is not important. Additionally, a primary key must exist, and only one data entry is allowed in each field. This answer covers all the necessary conditions for a table to be in a relation.

The correct answer suggests that the space of the object is a finite set of objects that are relevant to the problem being solved. It implies that the objects being considered are limited and specifically chosen based on their relevance to the problem at hand.

The given answer states that atomic data values are accessible based on the name of the relation, the name of the elementary attribute, and the quantitative value of the record identifier, while logical records are accessible based on the name of the relation and the quantitative value of the record identifier. This implies that atomic data values require additional information (the name of the elementary attribute) compared to logical records, which only require the name of the relation and the quantitative value of the record identifier.