TEST BORRADO, QUIZÁS LE INTERESE:
DAW1 BBDD Unidad5 Unidad6
COMENTARIOS |
ESTADÍSTICAS |
RÉCORDS
|
|---|
REALIZAR TEST
|
Título del Test:
DAW1 BBDD Unidad5 Unidad6 Descripción: Englisht Test Autor:
Fecha de Creación: 08/05/2024 Categoría: Informática Número Preguntas: 55 |
COMPARTE EL TEST
COMENTAR
No hay ningún comentario sobre este test.
Temario:
|
What is the main difference between PL/SQL and stored procedures in MySQL?
Select one: Stored procedures in MySQL allow the use of multiple programming languages, while PL/SQL is limited to a single language. PL/SQL is exclusive to Oracle Database, while MySQL stored procedures are supported by several database management systems. There is no difference, both terms refer to the same concept in different database management systems. PL/SQL is a procedural programming language developed by Oracle, while stored procedures in MySQL use a language similar to standard SQL. The command to view the definition of a stored procedure is: Select one: SHOW PROCEDURE <procedure_name> SHOW CREATE PROCEDURE <procedure_name> SHOW <procedure_name> None of the above. Using SET NEW.col_name = value and SET var_name = NEW.col_name requires the following privileges respectively: Select one: UPDATE and SELECT on the column. SELECT and UPDATE on the column. SELECT and DELETE on the column. None of the above. Among other features, stored procedures in MySQL allow: Select one: The functionality of SQL and the power of a declarative language. Execute functions and procedures in our programs through sophisticated drivers . Reduce network traffic in client-server environments. Indicate the correct statement. The control flow constructors are: Select one: IF, CASE, LOOP, WHILE, ITERATE and LEAVE. FOR loops are also supported. IF, CASE, LOOP, WHILE, ITERATE and LEAVE. FOR loops are not supported. ITERATE can only appear in LOOP commands. None of the above. The way to drop any tagged control flow in a stored procedure is with: Select one: LOOP LEAVE ITERATE None of the above. Error handling in MySQL stored procedures : Select one: We cannot control it since we will never know the errors that may occur. We control it through the handler. It is controlled by the compiler. The operation that we can use to obtain the rows of an open cursor is: Select one: CLOSE LEAVE FETCH DECLARE. The columns in the table associated with the trigger can be referenced using the aliases OLD and NEW. To reference a column of an existing row, before being updated or deleted we would use: Select one: OLD.col_name NEW.col_name It's indifferent None of the above. The statement SELECT id,data INTO x,y FROM test.t1 LIMIT 1; Select one: Enter the values of the attributes x and y results of the query into the id and data variables. Enter the values of the id and data attributes of the query into the x and y variables. The two previous. None of the above. The syntax to declare a cursor is as follows: DECLARE cursor_name CURSOR FOR select_statement. Indicate the false statements: Select one: Multiple cursors can be defined in a routine, but each cursor in a block must have a unique name. The SELECT command cannot have the INTO clause. The SELECT command can have the INTO clause. The sequences of operations to use with explicit cursors are: Select one: OPEN, DECLARE, FETCH, CLOSE DECLARE, OPEN, FETCH, CLOSE FETCH, DECLARE, OPEN, CLOSE None of the above. The statements that can activate the trigger (TRIGGER) are: Select one: CREATE, UPDATE and INSERT INSERT, UPDATE and DELETE INSERT, UPDATE and DROP None of the above. When you define a Trigger in MySQL, it can be of the type: Select one or more: Both BEFORE AFTER. For error handling we use: Select one: Cursors Handlers Triggers None of the above. To modify the control flow of a block in MySQL stored procedures we must: Select one: Use conditional control structures and iterative control structures. Use the cursors. We cannot modify the control flow within a block. For a handler to continue the current routine after the execution of the handler command, the type in the declaration should be: Select one: RESET EXIT CONTINUE UNDO. Select the correct statement: Select one: Stored procedures are useful when multiple client applications are written in different languages or run on different platforms, but need to perform the same operation on the database. Stored procedures can improve performance because less information needs to be sent between the server and the client. Stored procedures allow you to have libraries or functions on the database server. All of the above. None of the above. Select the INCORRECT answer: Select one: The RETURNS clause can be specified only with FUNCTION , where it is required. When a database is deleted, all stored procedures associated with it are NOT deleted. Stored procedures require proc table in MySQL database. A procedure is invoked using a CALL command, and can only return values using output variables. A trigger allows: Select one: Monitor the database to make it more efficient and take up less space. Ensure complex integrity rules. Compress the database by almost 50%. Change the delimiter to another value of “;” before creating a stored procedure serves to ignore the delimiter; used in the body of the procedure through the server instead of being interpreted by the server. True or false? True False. The trigger (TRIGGER) can be activated before (BEFORE) or after (AFTER) the statement that activates it. True or false? True False. Cursors must be declared after handlers. True or false? True False . Cursors DO NOT allow us to store a set of rows from a table in a data structure that we can cycle through sequentially. True or false? True False . We can define triggers at insert time but not at delete time. True or false? True False. A trigger must always end the statement RETURN. True or false? True False . A trigger (TRIGGER) is a named object in a database that is associated with a table, and is fired when a particular event occurs for that table. True or false? True False. That normal form that establishes that every determinant is a candidate key, among other restrictions, is called: Select one: 3NF 4NF BCNF 2NF. Which of the following is not a semantic restriction typical of generalizations/specializations? Select one: Bias Simplicity Overlap Whole. Which of the following is not considered a simplification of the conceptual schema of a database? Select one: Transformation of n-ary relations into binary ones. Reduction to one-to-many relationships. Elimination of double relationships. Elimination of recursive relationships. When we generate the conceptual schema of the database and later simplify it, we will look for it to contain only relationships... Select one: Ternaries Binary Double Unarias. Where would the issue date of an invoice be stored in a conceptual schema based on the Entity-Relationship model? Select one: All the answers are correct. In the CUSTOMER entity, INVOICE_NUMBER must be added to said entity. In the INVOICE entity. In the relationship that associates the entity INVOICE and CUSTOMER. In the Entity-Relationship model, key attributes are represented... Select one: No answer is correct. Using its underlined identifier, within an ellipse. Using its underlined identifier, next to a black circle. Using an asterisk next to the key identifier. Between entities, if a strong entity instance disappears and the weak entity instances that depend on the first one also disappear, considering that each occurrence of a weak entity can be identified by itself, we will be faced with: Select one: A dependency on identification. An existing dependency. A hierarchy of specialization. A weak entity. Indicate which statement is correct: Select one: All primary keys are usually formed from composite attributes. Primary keys must be multivalued attributes. The primary key can be composed of several attributes. A primary key must be atomic and multivalued. The graphical representation in the Extended Entity/Relationship model of an exclusivity restriction is done: Select one: Through an arc ending in an arrow, which will start from the relationship that must be fulfilled first towards the other relationship. Through a dashed line between the two relationships. Through an arc that encompasses all those relationships that are exclusive. Through a discontinuous line arc between the two relationships. The types of dependency in identification and existence correspond to: Select one: Strong entities. Weak entities. Candidate and primary keys. Hierarchies. We are in the normalization process. If we have to create, from the initial table, a new table with the attributes that do not have transitive dependencies on the primary key and in another table we place the non-key attributes that are involved in a transitive dependency, we are normalizing to ensure that said table is in: Select one: 1NF BCNF 2NF 3NF . Who defined the relational model and published a series of rules for the normalization of relational databases? Select one: No answer is correct. Edgar Frank Codd 1970. Peter P. Codd 1970. Peter P. Chen 1979. If when representing an entity in the Entity-Relationship model, none of the attributes written inside ellipses are underlined, we are faced with... Select one: A weak entity, if represented with a double rectangle. A strong entity. A hierarchy of specialization. A set of composite attributes. If in a table, an attribute functionally depends on a set of attributes and there is no possibility that it functionally depends on a subset of them, we say that we are faced with: Select one: All the answers are correct. A complete functional dependency. A transitive dependency. A functional dependency. If we are to represent the following requirement: "A job seeker can take several training courses and, in turn, a training course can be taken by several job seekers." What cardinality should be represented in the conceptual scheme to model this situation? Select one: A one to one relationship. A many-to-many relationship. A many to one relationship. A one to many relationship. A key or primary key is a... Select one: Optional attribute. Derived attribute. Mandatory attribute. Composite attribute. In the application of the Relational model to the conceptual scheme based on the Entity-Relationship model, each weak entity will generate a table that includes all its attributes. The attributes that are the primary key of the strong entity with which it is related will be added to this table. These added attributes are constituted as a foreign key that references the strong entity. Next, a primary key will be chosen for the created table. True or false? True False. In a relationship, if the existence of each of the occurrences of one of the entities requires at least one occurrence of the other entity, we will have a mandatory, total or total participation relationship. True or false? True False. In a relational database table, the number of attributes (columns or fields) cannot exceed 30. True or false? True False . The Semantic Correctness of a conceptual scheme will be achieved when the representations expressed in it mean exactly what is stipulated in the requirements. True or false? True False. Obtaining the Conceptual Scheme of the database is achieved in the Design Phase. True or false? True False . The attributes associated with a relationship are always represented by an ellipse, its identifier within it and a dashed line that joins the ellipse with the rhombus of the relationship. True or false? True False . To locate those elements that will be the entities of our schema, we will analyze the requirements specification in search of names or nouns. True or false? True False . For a table to be in 1NF , all non-key attributes must functionally depend on the primary key. True or false? True False. If in the cardinality of an entity we find the label (0,1) it will mean that the entity can not intervene in the relationship or intervene on a maximum of one occasion. True or false? True False. If we establish a simile with Object Oriented Programming, we can say that the concept of entity is analogous to that of class. True or false? True False . All possible values that an attribute can take must be within the domain. True or false? True False. A double rhombus represents a weak relationship. True or false? True False . |
Denunciar Test