What is a primary key in database? Give an example. -Technology

What is a primary key in database? Give an example. -Technology
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A field which uniquely identifies each record in a table is known as the primary key. e.g. emp id is the primary key of the Employee table.
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What is the utility of primary key in database? Write distinct features of primary keys. -Technology

Description : What is the utility of primary key in database? Write distinct features of primary keys. -Technology

Last Answer : The primary key is used to uniquely identify the record in a database. It can be a column or a set of columns in the table.Main features of the primary key are as follows:1. It must contain a unique value for each record of the table.2. It does not contain null values.

What is primary key? Give an example. -Technology

Description : What is primary key? Give an example. -Technology

Last Answer : A field which uniquely identifies each record in a table is known as the primary key. e.g. emp id is the primary key of the Employee table.

Define primary key with an example. -Technology

Description : Define primary key with an example. -Technology

Last Answer : A field which uniquely identifies each record in a table is known as the primary key. e.g. emp id is the primary key of the Employee table.

Give one advantage of using primary key. -Technology

Description : Give one advantage of using primary key. -Technology

Last Answer : A primary key uniquely identifies the record in the table.

What is database? Give example. -Technology

Description : What is database? Give example. -Technology

Last Answer : A collection of related information organized as tables is known as the database, e.g. INGRES, MySQL etc.

What is field in database? Give an example. -Technology

Description : What is field in database? Give an example. -Technology

Last Answer : A field is an area, reserved for a specific piece of data. It is also known as an attribute, e.g. Customer_Name.

What is a primary key? -Technology

Description : What is a primary key? -Technology

Last Answer : A field which uniquely identifies each record in a table is known as the primary key. e.g. emp id is the primary key of the Employee table.

What is the significance of a primary key? -Technology

Description : What is the significance of a primary key? -Technology

Last Answer : A primary key cannot allow null values and must have a unique index.

Which of the following fields will not make a suitable primary key? (a) A customer’s account number -Technology

Description : Which of the following fields will not make a suitable primary key? (a) A customer’s account number -Technology

Last Answer : (b) From the given options, the data field can not be set as a primary key because it can’t be fixed for an object.

Primary key is used to …………….. identify the record. -Technology

Description : Primary key is used to …………….. identify the record. -Technology

Last Answer : Primary key is used to uniquelyidentify the record.

The candidate key, which is not used as primary key is called ………….. key. -Technology

Description : The candidate key, which is not used as primary key is called ………….. key. -Technology

Last Answer : The candidate key, which is not used as primary key is calledalternate key.

Primary key field gives us permission to record duplicate entry. -Technology

Description : Primary key field gives us permission to record duplicate entry. -Technology

Last Answer : False A primary key is a key which identifies records uniquely in a table so it does not give us permission to record duplicate entry.

A primary key field does not allow numbers. -Technology

Description : A primary key field does not allow numbers. -Technology

Last Answer : False Primary key has to identify a unique value which can be present in a table, in a number form also. It means primary key field allow number too.

A primary key value can be NULL. -Technology

Description : A primary key value can be NULL. -Technology

Last Answer : False The primary key of table is used to uniquely identify each and every row in the table. So, its all keys and columns must be defined as NOT NULL.

A foreign key is a primary key in another table. -Technology

Description : A foreign key is a primary key in another table. -Technology

Last Answer : True When a table’s primary key field is added to a related table in order to create the common field which relates two tables, it is called a foreign key in the related table.

What is a primary key? How do we set a primary key? -Technology

Description : What is a primary key? How do we set a primary key? -Technology

Last Answer : Primary key is the key which is used to uniquely identify the records into the table. To set the primary key you have to follow the steps given below:Step 1 Select the field that you want ... 2 Click Primary Key button from the Design tab.orRight click on the selected field and select Primary Key.

Define primary key. How do you set it in MS_Access? -Technology

Description : Define primary key. How do you set it in MS_Access? -Technology

Last Answer : Primary key is the key which is used to uniquely identify the records into the table. To set the primary key you have to follow the steps given below:Step 1 Select the field that you want ... 2 Click Primary Key button from the Design tab.orRight click on the selected field and select Primary Key.

…………. is a field which is used as a primary key and numbers each record sequentially. -Technology

Description : …………. is a field which is used as a primary key and numbers each record sequentially. -Technology

Last Answer : AutoNumberis a field which is used as a primary key and numbers each record sequentially.

What is a primary key in a table? -Technology

Description : What is a primary key in a table? -Technology

Last Answer : A primary key is a special relational database table column (or combination of columns) designated to uniquely identify each & every table record. It does not contain NULL & duplicate values

Write any one similarity and one difference between primary key and unique Constraint. -Technology

Description : Write any one similarity and one difference between primary key and unique Constraint. -Technology

Last Answer : Similarity: Column with both the constraints will only take unique values.Difference: Column with Primary key constraints will not be able to hold NULL values while Column with Unique constraints will be able to hold NULL values.

Identify the primary key column of Train and Reservation. -Technology

Description : Identify the primary key column of Train and Reservation. -Technology

Last Answer : (i) Train-TrainIdReservation-RefNo(ii) (d) By default, the UNION operator selects all the values.

Write any one similarity and one difference between primary key and unique Constraint -Technology

Description : Write any one similarity and one difference between primary key and unique Constraint -Technology

Last Answer : Similarity: Column with both the constraints will only take unique values.Difference: Column with Primary key constraints will not be able to hold NULL values while Column with Unique constraints will be able to hold NULL values.

Which of the following is not an example of database? (a) Cross knot game -Technology

Description : Which of the following is not an example of database? (a) Cross knot game -Technology

Last Answer : (c) Numeric calculator because it is used to calculate the numeric numbers only as it is unable to store data.

Mention any two example of common Database Management System. -Technology

Description : Mention any two example of common Database Management System. -Technology

Last Answer : MySQL, Ingres, Postgres, Oracle etc.

Consider the following database table : Create table test( one integer, two integer, primary key(one), unique(two), check(one≥1 and ≤10), check(two≥1 and ≤5) ); How many data records/tuples atmost can this table contain ? (A) 5 (B) 10 (C) 15 (D) 50

Description : Consider the following database table : Create table test( one integer, two integer, primary key(one), unique(two), check(one≥1 and ≤10), check(two≥1 and ≤5) ); How many data records/tuples atmost can this table contain ?  (A) 5 (B) 10 (C) 15 (D) 50

Last Answer : (A) 5 

In a relational database model, NULL values can be used for all but which one of the following? (A) To allow duplicate tuples in the table by filling the primary key column(s) with NULL. (B) To avoid confusion with actual legitimate data values like 0 (zero) for integer columns and ‘’ (the empty string) for string columns. (C) To leave columns in a tuple marked as “unknown” when the actual value is unknown. (D) To fill a column in a tuple when that column does not really “exist” for that particular tuple.

Description : In a relational database model, NULL values can be used for all but which one of the following? (A) To allow duplicate tuples in the table by filling the primary key column(s) with NULL. (B) To ... D) To fill a column in a tuple when that column does not really exist for that particular tuple.

Last Answer : (A) To allow duplicate tuples in the table by filling the primary key column(s) with NULL.

Give any one use of database. -Technology

Description : Give any one use of database. -Technology

Last Answer : A database is used to store logically related information in the table.

Give any two disadvantages of the database. -Technology

Description : Give any two disadvantages of the database. -Technology

Last Answer : 1. High complexity2. Database failure

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Description : Give five names of database templates used in MS_Access 2007. -Technology

Last Answer : Assets, Contacts, Events, Faculty and Issues.

What is database template? Give the description of five templates, used in Microsoft Access 2007. -Technology

Description : What is database template? Give the description of five templates, used in Microsoft Access 2007. -Technology

Last Answer : A template is a complete tracking application with predefined tables, forms, reports, queries, macros, and relationships. Each template creates a complete end-to-end solution that you can use ... to create a projects tracking database to track multiple projects and assign tasks to different people.

What is part of a database that holds only one type of information? -Technology

Description : What is part of a database that holds only one type of information? -Technology

Last Answer : Field. Record. is the answer

A software that searches through a database of Web pages for particular information is known as (a) domain -Technology

Description : A software that searches through a database of Web pages for particular information is known as (a) domain -Technology

Last Answer : (d) Search engine searches a software through a database of Web pages for particular information.

Explain Database Management. What are the features of DBMS? -Technology

Description : Explain Database Management. What are the features of DBMS? -Technology

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Write the relationship between a database and a table. -Technology

Description : Write the relationship between a database and a table. -Technology

Last Answer : A database contains multiple tables whereas, a table cannot exist outside a database.

Write any two advantages of using database. -Technology

Description : Write any two advantages of using database. -Technology

Last Answer : 1. Can ensure data security.2. Reduces the data redundancy.

Write any two uses of database management system. -Technology

Description : Write any two uses of database management system. -Technology

Last Answer : 1. DBMS is used to store data at a centralized location.2. It is used to minimize data redundancy and data inconsistency.

What is the default extension of OO.o not zero BASE database? -Technology

Description : What is the default extension of OO.o not zero BASE database? -Technology

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What are the main purposes of a database system? -Technology

Description : What are the main purposes of a database system? -Technology

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Define query in the context of database. -Technology

Description : Define query in the context of database. -Technology

Last Answer : A query is an inquiry into the database using the SELECT statement. These statements give you filtered data according to your conditions and specifications indicating the fields, records, and summaries which a user wants to fetch from a database.

Below is the list of various types of application softwares: A. Database B. Desktop publishing C. Drawing -Technology

Description : Below is the list of various types of application softwares: A. Database B. Desktop publishing C. Drawing -Technology

Last Answer : 1. Drawing2. Word processing3. Desktop publishing4. Spreadsheet5. Database

Discuss the components of a database. -Technology

Description : Discuss the components of a database. -Technology

Last Answer : A database consists of several components. Each component plays an important role in the database system environment.The major components of the database are as follows:DataIt is raw numbers, ... perform different operations on the database by inserting, deleting etc., through menus or forms.

Define database management system. Write two advantages of using database management system for school. -Technology

Description : Define database management system. Write two advantages of using database management system for school. -Technology

Last Answer : Database Management System (DBMS) is a collection of programs that enable users to create, maintain database and control all the access to the database. The primary goal of the DBMS is to ... centralized location.2. It provides security to the personal information of the school, stored in it.

Write the steps to design a database. -Technology

Description : Write the steps to design a database. -Technology

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Consider the following database Student:Roll No. First Name Last Name Class Marks Obtained(%) Scholarship Awarded -Technology

Description : Consider the following database Student:Roll No. First Name Last Name Class Marks Obtained(%) Scholarship Awarded -Technology

Last Answer : 1. 95.42. Mohan Garg and scholarship awarded is 50000.3. 54. 6

The director of a company uses a database to store data about job title. This is a part of the database given below: -Technology

Description : The director of a company uses a database to store data about job title. This is a part of the database given below: -Technology

Last Answer : 1. 62. 63. Secretary4. Finance department and their Payroll Numbers are A621 and M502.

Database is a combination of (a) hardware and software -Technology

Description : Database is a combination of (a) hardware and software -Technology

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Operations performed on a database are controlled by (a) user (b) hardware -Technology

Description : Operations performed on a database are controlled by (a) user (b) hardware -Technology

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Database is made up of all the following components except (a) tables (b) queries -Technology

Description : Database is made up of all the following components except (a) tables (b) queries -Technology

Last Answer : (d) A database is made up of tables, queries, and forms.

All the information about a thing or a person is known as a (a) database (b) file -Technology

Description : All the information about a thing or a person is known as a (a) database (b) file -Technology

Last Answer : (d) A record refers to a raw of data, which represents a complete set of information in a table.