Why is it preferable to create a fewer no. of queries in the data model?

Why is it preferable to create a fewer no. of queries in the
data model?
by

1 Answer

Answer :

Because for each query, report has to open a separate cursor and has
to rebind, execute and fetch data.
by

Related questions

How can one optimize %XYZ% queries? (for DBA

Description : How can one optimize %XYZ% queries? (for DBA

Last Answer : It is possible to improve %XYZ% queries by forcing the optimizer to scan all the entries from the index instead of the table. This can be done by specifying hints. If the index is physically smaller than ... the case) it will take less time to scan the entire index than to scan the entire table.

Which parameter can be used to set read level consistency across multiple queries?

Description : Which parameter can be used to set read level consistency across multiple queries?

Last Answer : Read only

Is it possible to insert comments into sql statements return in the data model editor?

Description : Is it possible to insert comments into sql statements return in the data model editor?

Last Answer : Yes

Atleast how many set of data must a data model have before a data model can be base on it?

Description : Atleast how many set of data must a data model have before a data model can be base on it?

Last Answer : Four

Does a grouping done for objects in the layout editor affect the grouping done in the data model editor?

Description : Does a grouping done for objects in the layout editor affect the grouping done in the data model editor?

Last Answer : No.

If two groups are not linked in the data model editor, What is the hierarchy between them?

Description : If two groups are not linked in the data model editor, What is the hierarchy between them?

Last Answer : Two group that is above are the left most rank higher than the group that is to right or below it.

What is Data Model?

Description : What is Data Model?

Last Answer : A collection of conceptual tools for describing data, data relationships data semantics and constraints.

The ______ are programs that run on DNS clients and DNS servers and that create queries to extract information from name servers. A. transporter B. distributers C. Resolvers D. both a and b

Description : The ______ are programs that run on DNS clients and DNS servers and that create queries to extract information from name servers. A. transporter B. distributers C. Resolvers D. both a and b

Last Answer : C. Resolvers

Which of the following practices are not suggested for producing relevant content? a. For creating notable content recurrently, create hero "content for tent-pole events". b. For creating valuable content constantly, create a series of scheduled hub" content." c. For creating more content than your competitors, create lots of articles that are short, unsubstantial, or otherwise lacking in helpful specifics. d. For creating relevant content consistently, create help" content to answer queries."

Description : Which of the following practices are not suggested for producing relevant content? a. For creating notable content recurrently, create hero "content for tent-pole events". b. For creating ... specifics. d. For creating relevant content consistently, create help" content to answer queries."

Last Answer : c. For creating more content than your competitors, create lots of articles that are short, unsubstantial, or otherwise lacking in helpful specifics.

Which of the following is NOT a best practice for producing content? A. To produce remarkable content frequently, create hero "content for tent-pole events." B. To produce valuable content consistently, create a series of scheduled hub" content." C. To produce more content that your competitors, create lots of articles that are short, unsubstantial, or otherwise lacking in helpful specifics. D. To produce relevant content consistently, create help" content to answer queries."

Description : Which of the following is NOT a best practice for producing content? A. To produce remarkable content frequently, create hero "content for tent-pole events." B. To produce valuable content ... helpful specifics. D. To produce relevant content consistently, create help" content to answer queries."

Last Answer : C. To produce more content that your competitors, create lots of articles that are short, unsubstantial, or otherwise lacking in helpful specifics

In practice, which Life Cycle model may have more, fewer or different levels of development and testing, depending on the project and the software product. For example, there may be component integration testing after component testing, andsystem integration testing after system testing. A. Water Fall Model B.V-Model C. Spiral Model D. RAD Model

Description : In practice, which Life Cycle model may have more, fewer or different levels of development and testing, depending on the project and the software product. For example, there may be component integration testing ... after system testing. A. Water Fall Model B.V-Model C. Spiral Model D. RAD Model

Last Answer : B.V-Model

In practice, which Life Cycle model may have more, fewer or different levels of development and testing, depending on the project and the software product. For example, there may be component integration testing after component testing, and

Description : In practice, which Life Cycle model may have more, fewer or different levels of development and testing, depending on the project and the software product. For example, there may be component integration testing after component testing, and

Last Answer : B.V-Model

Goals for the design of thelogical schema include A. avoiding data inconsistency B. being ableto construct queries easily C. being ableto access data efficiently D. All of theabove E. None of the above

Description : Goals for the design of thelogical schema include A. avoiding data inconsistency B. being ableto construct queries easily C. being ableto access data efficiently D. All of theabove E. None of the above

Last Answer : All of theabove

Report generatorsare usedto A. store data input bya user B. retrieve information from files C. answer queries D. both (b)and (c) E. None of the above

Description : Report generatorsare usedto A. store data input bya user B. retrieve information from files C. answer queries D. both (b)and (c) E. None of the above

Last Answer : both (b)and (c)

Which of the following describes a relational database? 1) It provides a relationship between integers 2) It consists of separate tables or related data 3) It retrieves data related to its queries 4) It provides a relationship between floats

Description : Which of the following describes a relational database? 1) It provides a relationship between integers 2) It consists of separate tables or related data 3) It retrieves data related to its queries 4) It provides a relationship between floats

Last Answer : 2) It consists of separate tables or related data

Which of the following is a structured data store that supports indexing and data queries to both EC2 and S3? a) CloudWatch b) Amazon SimpleDB c) Amazon Cloudfront d) All of the mentioned

Description : Which of the following is a structured data store that supports indexing and data queries to both EC2 and S3? a) CloudWatch b) Amazon SimpleDB c) Amazon Cloudfront d) All of the mentioned

Last Answer : Amazon SimpleDB

Which of the following is/are the Database server functions? i) Data management ii) Transaction management iii) Compile queries iv) Query optimization A) i, ii, and iv only B) i, ii and iii only C) ii, iii and iv only D) All i, ii, iii, and iv

Description : Which of the following is/are the Database server functions? i) Data management ii) Transaction management iii) Compile queries iv) Query optimization A) i, ii, and iv only B) i, ii and iii only C) ii, iii and iv only D) All i, ii, iii, and iv

Last Answer : A) i, ii, and iv only

Consider the following three SQL queries (Assume the data in the people table) : (a) Select Name from people where Age>21; (b) Select Name from people where Height>180; (c) Select Name from people where (Age>21) or (Height>180); If the SQL queries (a) and (b) above, return 10 rows and 7 rows in the result set respectively, then what is one possible number of rows returned by the SQL query (c) ? (A) 3 (B) 7 (C) 10 (D) 21

Description : Consider the following three SQL queries (Assume the data in the people table) : (a) Select Name from people where Age>21; (b) Select Name from people where Height>180; (c) Select Name from people where (Age>21) or (Height ... number of rows returned by the SQL query (c) ? (A) 3 (B) 7 (C) 10 (D) 21

Last Answer : (C) 10

What is Object Oriented model?

Description : What is Object Oriented model?

Last Answer : This model is based on collection of objects. An object contains values stored in instance variables with in the object. An object also contains bodies of code that operate on the object. These ... . Objects that contain same types of values and the same methods are grouped together into classes.

What is E-R model?

Description : What is E-R model?

Last Answer : This data model is based on real world that consists of basic objects called entities and of relationship among these objects. Entities are described in a database by a set of attributes.

The Relational Model Database:

Description : The Relational Model Database:

Last Answer : The relational model is the most popular type of database and an extremely powerful tool, not only to store information, but to access it as well. Relational databases are organized as tables. The ... reorganizing the tables. A table can have many records and each record can have many fields.

The Network Model Database:

Description : The Network Model Database:

Last Answer : In a network model, the defining feature is that a record is stored with a link to other records – in effect networked. These networks (or sometimes referred to as pointers) can be a variety of different types of information such as node numbers or even a disk address.

The Hierarchical Model Database:

Description : The Hierarchical Model Database:

Last Answer : The hierarchical model database resembles a tree like structure, such as how Microsoft Windows organizes folders and files. In a hierarchical model database, each upward link is nested in order to keep data ... Within this nested file are all of the sales (same types of data) for the day.

The Flat Model Database:

Description : The Flat Model Database:

Last Answer : In a flat model database, there is a two dimensional (flat structure) array of data. For instance, there is one column of information and within this column it is assumed that each data item will be related ... will only be one column and each new row within that one column will be a new zip code.

How does one create a standby database? (for DBA)

Description : How does one create a standby database? (for DBA)

Last Answer : While your production database is running, take an (image copy) backup and restore it on duplicate hardware. Note that an export will not work!!! On your standby database, issue ... the standby database, stop the recovery process and activate it: ALTER DATABASE ACTIVATE STANDBY DATABASE;

Name a tablespace automatically created when you create a database.

Description : Name a tablespace automatically created when you create a database.

Last Answer : The SYSTEM tablespace.

What command would you use to create a backup control file?

Description : What command would you use to create a backup control file?

Last Answer : Alter database backup control file to trace.

A table is classified as a parent table and you want to drop and re-create it. How would you do this without affecting the children tables?

Description : A table is classified as a parent table and you want to drop and re-create it. How would you do this without affecting the children tables?

Last Answer : Disable the foreign key constraint to the parent, drop the table, re- create the table, enable the foreign key constraint.

Which parameter specified in the DEFAULT STORAGE clause of CREATE TABLESPACE cannot be altered after creating the tablespace?

Description : Which parameter specified in the DEFAULT STORAGE clause of CREATE TABLESPACE cannot be altered after creating the tablespace?

Last Answer : All the default storage parameters defined for the tablespace can be changed using the ALTER TABLESPACE command. When objects are created their INITIAL and MINEXTENS values cannot be changed.

How does one create and drop database users?

Description : How does one create and drop database users?

Last Answer : Look at these examples: CREATE USER scott IDENTIFIED BY tiger -- Assign password DEFAULT TABLESACE tools -- Assign space for table and index segments TEMPORARY TABLESPACE temp; -- Assign sort space ... give the user some space quota on its tablespaces: ALTER USER scott QUOTA UNLIMITED ON tools;

What utility is used to create a physical backup?

Description : What utility is used to create a physical backup?

Last Answer : Either rman or alter tablespace begin backup will do..

The following describes means to create a OEM V1.x (very old!!!) repository on WindowsNT:

Description : The following describes means to create a OEM V1.x (very old!!!) repository on WindowsNT:

Last Answer : Create a tablespace that would hold the repository data. A size between 200- 250 MB would be ideal. Let us call it Dummy_Space. . Create an Oracle user who would own this repository. Assign ... would trigger the creation of the repository. From now on, Enterprise manager is ready to accept jobs.

How does one create a repository? (for DBA

Description : How does one create a repository? (for DBA

Last Answer : For OEM v2 and above, start the Oracle Enterprise Manager Configuration Assistant (emca on Unix) to create and configure the management server and repository. Remember to setup a backup for the repository database after creating it.

What are the built-in routines is available in forms 4.0 to create and manipulate a parameter list?

Description : What are the built-in routines is available in forms 4.0 to create and manipulate a parameter list?

Last Answer : Add_parameter Create_Parameter_list Delete_parameter Destroy_parameter_list Get_parameter_attr Get_parameter_list set_parameter_attr

Can we create two blocks with the same name in form 3.0 ?

Description : Can we create two blocks with the same name in form 3.0 ?

Last Answer : No

How will you create multiple rollback segments in a database ?

Description : How will you create multiple rollback segments in a database ?

Last Answer : Create a database which implicitly creates a SYSTEM Rollback Segment in a SYSTEM tablespace. Create a Second Rollback Segment name R0 in the SYSTEM tablespace. Make new rollback segment ... ) for rollback segments. Deactivate Rollback Segment R0 and activate the newly created rollback segments.

How does one create a RMAN recovery catalog? (for DBA

Description : How does one create a RMAN recovery catalog? (for DBA

Last Answer : Start by creating a database schema (usually called rman). Assign an appropriate tablespace to it and grant it the recovery_catalog_owner role. Look at this example: sqlplus sys SQL>create user ... . Look at this example: rman catalog rman/rman target backdba/backdba RMAN> register database;

How does one create a password file? (for DBA

Description : How does one create a password file? (for DBA

Last Answer : The Oracle Password File ($ORACLE_HOME/dbs/orapw or orapwSID) stores passwords for users with administrative privileges. One needs to create a password files before remote administrators (like OEM) will be ... visible in the process table of many systems. Administrators needs to be aware of this!

How do you create a new session while open a new form?

Description : How do you create a new session while open a new form?

Last Answer : Using open_form built-in setting the session option Ex. Open_form('Stocks ',active,session). when invoke the mulitiple forms with open form and call_form in the same application, state whether the following are true/False

How does one create a new database? (for DBA)

Description : How does one create a new database? (for DBA)

Last Answer : One can create and modify Oracle databases using the Oracle "dbca" (Database Configuration Assistant) utility. The dbca utility is located in the $ORACLE_HOME/bin directory. The Oracle Universal ... ='/u02/oradata/'; ALTER SYSTEM SET DB_CREATE_ONLINE_LOG_DEST_2='/u03/oradata/'; CREATE DATABASE;

A Column is having many repeated values which type of index you should create on this column, if you have to?

Description : A Column is having many repeated values which type of index you should create on this column, if you have to?

Last Answer : For example, assume there is a motor vehicle database with numerous low-cardinality columns such as car_color, car_make, car_model, and car_year. Each column contains less than 100 distinct values by themselves, and a b tree index would be fairly useless in a database of 20 million vehicles.

A table is having few rows, should you create indexes on this table

Description : A table is having few rows, should you create indexes on this table

Last Answer : Small tables do not require indexes; if a query is taking too long, then the table might have grown from small to large. You can create an index on any column; however, if the ... , creating an index on the column does not increase performance and the index takes up resources unnecessarily.

On which columns you should create Indexes?

Description : On which columns you should create Indexes?

Last Answer : In general, you should create an index on a column in any of the following situations: ▪ The column is queried frequently ▪ A referential integrity constraint exists on the column ▪ A UNIQUE key ... ORDER BY clauses ▪ On columns that have few of the same values or unique values in the table

Which default Database roles are created when you create a Database?

Description : Which default Database roles are created when you create a Database?

Last Answer : CONNECT , RESOURCE and DBA are three default roles. The DBA_ROLES data dictionary view can be used to list all roles of a database and the authentication used for each role. The following query lists all the roles in ... ------------ -------- CONNECT NO RESOURCE NO DBA NO SECURITY_ADMIN YES

What is the minimum number of instances you need to have in order to create a RAC?

Description : What is the minimum number of instances you need to have in order to create a RAC?

Last Answer : 1. You can create a RAC with just one server.

You want to understand if users use their mobile phone to access your site. Which of the following approach is preferable? A. Ask "Are you using a mobile phone to access our site?" Yes/No B. Ask "Which type of device are you using to access our site?" with choices: Desktop computer/Mobile Phone/Tablet C. Look at the report Audience/Mobile/Overview D. This cannot be known because people use multiple devices to browse the Web

Description : You want to understand if users use their mobile phone to access your site. Which of the following approach is preferable? A. Ask "Are you using a mobile phone to access our site?" ... report Audience/Mobile/Overview D. This cannot be known because people use multiple devices to browse the Web

Last Answer : C. Look at the report Audience/Mobile/Overview

The join defined by the default data link is an outer join yes or no?

Description : The join defined by the default data link is an outer join yes or no?

Last Answer : Yes

Difference between NO DATA FOUND and %NOTFOUND?

Description : Difference between NO DATA FOUND and %NOTFOUND?

Last Answer : NO DATA FOUND is an exception raised only for the SELECT....INTO statements when the where clause of the querydoes not match any rows. When the where clause of the explicit cursor does not match any rows the %NOTFOUND attribute is set to TRUE instead.

Division operation is ideally suited to handle queries of the type : (A) customers who have no account in any of the branches in Delhi. (B) customers who have an account at all branches in Delhi. (C) customers who have an account in atleast one branch in Delhi. (D) customers who have only joint account in any one branch in Delhi

Description : Division operation is ideally suited to handle queries of the type : (A) customers who have no account in any of the branches in Delhi. (B) customers who have an account at all branches in Delhi. ( ... atleast one branch in Delhi. (D) customers who have only joint account in any one branch in Delhi

Last Answer : (B) customers who have an account at all branches in Delhi. 

The basic idea behind Huffman coding is to A. compress data by using fewer bits to encode fewer frequently occuring characters B. compress data by using fewer bits to encode more frequently occuring characters C. compress data by using more bits to encode more frequently occuring characters D. expand data by using fewer bits to encode more frequently occuring characters

Description : The basic idea behind Huffman coding is to A. compress data by using fewer bits to encode fewer frequently occuring characters B. compress data by using fewer bits to encode more ... frequently occuring characters D. expand data by using fewer bits to encode more frequently occuring characters

Last Answer : B. compress data by using fewer bits to encode more frequently occuring characters