What is a primary key? -Technology

What is a primary key? -Technology
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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.
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Related questions

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.

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.

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

Description : What is a primary key in database? 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.

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 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.

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.

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.

Write the significance of a foreign key. -Technology

Description : Write the significance of a foreign key. -Technology

Last Answer : A foreign key is used to Establish the relationship between any two tables of RDBMS.

Key field is a unique identifier for each record. It is defined in the form of (a) rows (b) columns -Technology

Description : Key field is a unique identifier for each record. It is defined in the form of (a) rows (b) columns -Technology

Last Answer : (b) Key is a data item that allows you to uniquely identify individual occurrences which is defined as the column or set of columns.

A foreign key is a reference of the ………….. key in another table. -Technology

Description : A foreign key is a reference of the ………….. key in another table. -Technology

Last Answer : A foreign key is a reference of the primary keyin another table.

Which shortcut key is used to make the selected text italic? (a) Ctrl +I (b) Shift +I (c) F1 + I (d) None of these -Technology

Description : Which shortcut key is used to make the selected text italic? (a) Ctrl +I (b) Shift +I (c) F1 + I (d) None of these -Technology

Last Answer : (a) Ctrl+I is the shortcut key to make the selected text italic.

What is the use of Enter and Esc key in a Slide Show? -Technology

Description : What is the use of Enter and Esc key in a Slide Show? -Technology

Last Answer : Press Enter to move to the next slide and Esc to close the Slide Show.

Set new timing, while rehearsing ……………… key is press. (a) Ctrl+T (b) T (c) M (d) O -Technology

Description : Set new timing, while rehearsing ……………… key is press. (a) Ctrl+T (b) T (c) M (d) O -Technology

Last Answer : (b) T key is used to set new timing while rehearsing.

What is the shortcut key to display the Microsoft PowerPoint shortcut menu? -Technology

Description : What is the shortcut key to display the Microsoft PowerPoint shortcut menu? -Technology

Last Answer : (c) Shift + F10 is the shortcut key to display the PowerPoint shortcut menu

F4 key is used to start a Slide Show. -Technology

Description : F4 key is used to start a Slide Show. -Technology

Last Answer : FalseF5 key is used to start a Slide Show.

The contents of a cell can be changed by pressing F2 key on keyboard. -Technology

Description : The contents of a cell can be changed by pressing F2 key on keyboard. -Technology

Last Answer : True F2 is a shortcut for making the cell editable.

Control Unit is called the ………….. of a computer system. (a) heart (b) nerve centre (c) primary memory (d) All of these -Technology

Description : Control Unit is called the ………….. of a computer system. (a) heart (b) nerve centre (c) primary memory (d) All of these -Technology

Last Answer : (b) Nerve centre because it controls the overall processing of a computer system.

…… memory is used to store large amount of information permanently. (a) RAM (b) ROM (c) Secondary (d) Primary -Technology

Description : …… memory is used to store large amount of information permanently. (a) RAM (b) ROM (c) Secondary (d) Primary -Technology

Last Answer : (c) Secondary memory is used to store large amount of information permanently.

Which of the following statement is false? (a) Secondary storage is faster (b) Primary storage is both volatile and non volatile in nature. -Technology

Description : Which of the following statement is false? (a) Secondary storage is faster (b) Primary storage is both volatile and non volatile in nature. -Technology

Last Answer : (a) Secondary memory is the slowest and cheapest form of memory. It cannot be processed directly by the CPU and it must be first copied into RAM.

State the primary goal of a DBMS. -Technology

Description : State the primary goal of a DBMS. -Technology

Last Answer : To provide a convenient and efficient environment in which we can store and retrieve information.

Name two possible primary keys for an Employee table. -Technology

Description : Name two possible primary keys for an Employee table. -Technology

Last Answer : Possible primary keys for an Employee table are emp code, emp phone number.

A table can have multiple primary keys. -Technology

Description : A table can have multiple primary keys. -Technology

Last Answer : False If we create multiple primary keys in a table, the primary key will be unable to find the unique key value.

What are the primary interest of online attackers in spyware? -Technology

Description : What are the primary interest of online attackers in spyware? -Technology

Last Answer : Primary interest of online attackers in spyware is using it to steal personal information for financial crimes such as carding and identity theft or to sell that information to someone else who then executes more traditional financial crimes.

Name the primary law in India dealing with cyber crime and electronic commerce. -Technology

Description : Name the primary law in India dealing with cyber crime and electronic commerce. -Technology

Last Answer : The primary law is Information Technology Act 2000.

Have you ever accidentally activated the panic button on your vehicles key ring fob?

Description : Have you ever accidentally activated the panic button on your vehicles key ring fob?

Last Answer : Yes, once a month it seems.

MySQL order by primary key, put one row on top.

Description : MySQL order by primary key, put one row on top.

Last Answer : answer:If you can guarantee that there is only one or zero active records select * from presets order by active asc, id asc

Explain when the primary key fields of two data tables need to be the same. ?

Description : Explain when the primary key fields of two data tables need to be the same. ?

Last Answer : Due to the following condition of the relation, the primary key fields of the data tables of the two databases need to be the same to create the relation. 1. The common field must be the primary key ... field size , format etc. should be the same and two tables should be open at the same time.

What is a composite primary key field ?

Description : What is a composite primary key field ?

Last Answer : Answer : A combination of two or more attributes or keys can collectively identify an NTT set, but they are called composite primary keys.

What is the primary key field ?

Description : What is the primary key field ?

Last Answer : The field in the data table by which the values ​​of a record can be completely distinguished from other records is called the primary key.

The primary advantage of key-to-tape data entry system is A) A large percentage of editing can be performed at the time of data entry B) Key verification is easily performed C) The tape is reusable D) Keying errors can be detected as they occur.

Description : The primary advantage of key-to-tape data entry system is A) A large percentage of editing can be performed at the time of data entry B) Key verification is easily performed C) The tape is reusable D) Keying errors can be detected as they occur.

Last Answer : Answer : C

What is the difference between candidate key, unique key and primary key

Description : What is the difference between candidate key, unique key and primary key

Last Answer : Candidate keys are the columns in the table that could be the primary keys and the primary key is the key that has been selected to identify the rows. Unique key is also useful for identifying the distinct rows in the table.)

What is difference between UNIQUE and PRIMARY KEY constraints?

Description : What is difference between UNIQUE and PRIMARY KEY constraints?

Last Answer : A table can have only one PRIMARY KEY whereas there can be any number of UNIQUE keys. The columns that compose PK are automatically define NOT NULL, whereas a column that compose a UNIQUE is not automatically defined to be mandatory must also specify the column is NOT NULL.

Can a primary key contain more than one columns?

Description : Can a primary key contain more than one columns?

Last Answer : Yes

What is difference between UNIQUE constraint and PRIMARY KEY constraint ?

Description : What is difference between UNIQUE constraint and PRIMARY KEY constraint ?

Last Answer : A column defined as UNIQUE can contain Nulls while a column defined as PRIMARY KEY can't contain Nulls.

The primary advantage of key-to-tape data entry system is a. A large percentage of editing can be performed at the time of data entry b. Key verification is easily performed c. The tape is reusable d. Keying errors can be detected as they occur

Description : The primary advantage of key-to-tape data entry system is a. A large percentage of editing can be performed at the time of data entry b. Key verification is easily performed c. The tape is reusable d. Keying errors can be detected as they occur

Last Answer : The tape is reusable

What is the difference between unique key and primary key ?

Description : What is the difference between unique key and primary key ?

Last Answer : Unique key can be null; Primary key cannot be null.

What is difference between UNIQUE constraint and PRIMARY KEY constraint?

Description : What is difference between UNIQUE constraint and PRIMARY KEY constraint?

Last Answer : A column defined as UNIQUE can contain Nulls while a column defined as PRIMARY KEY can’t contain Nulls. 47.What is Index Cluster? – A Cluster with an index on the Cluster Key 48.When does a Transaction end? – When it is committed or Rollbacked.