Tag: sql

Questions Related to sql

What does SQL stand for?

sql

  1. Strong Question Language

  2. Structured Question Language

  3. Structured Query Language

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Correct Option: C

Which SQL statement is used to extract data from a database?

sql

  1. GET

  2. OPEN

  3. EXTRACT

  4. SELECT

  5. QUERY

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Correct Option: D
Explanation:

To extract data from a database using SQL, the correct option is D. SELECT.

Explanation:

The SELECT statement is used to extract or retrieve data from a database. It is one of the most commonly used SQL statements and forms the core of most database queries. The SELECT statement is followed by the columns or fields that need to be retrieved from the table or tables specified in the FROM clause. The WHERE clause can be used to filter the results based on specific conditions.

Let's go through each option and explain why it is right or wrong:

A. GET: This option is not a valid SQL statement. GET is not a SQL keyword and is not used to extract data from a database.

B. OPEN: This option is not used to extract data from a database. OPEN is used to open a cursor variable, which can then be used to fetch data from a result set.

C. EXTRACT: This option is used to extract parts of a date or time value such as year, month, day, hour, minute, or second. It is not used to extract data from a database table.

D. SELECT: This option is the correct answer. The SELECT statement is used to extract or retrieve data from a database.

E. QUERY: This option is not a specific SQL statement. Query is a general term used to refer to any SQL statement that retrieves data from a database. However, it is not a specific SQL keyword used to extract data.

Therefore, the answer is:

The Answer is: D. SELECT

Which SQL statement is used to update data in a database?
sql

  1. UPDATE

  2. SAVE AS

  3. MODIFY

  4. SAVE

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Correct Option: A

Which SQL statement is used to delete data from a database?

sql

  1. TRUNCATE

  2. DELETE

  3. REMOVE

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Correct Option: B

Which SQL statement is used to insert new data in a database?
sql

  1. ADD RECORD

  2. ADD INTO

  3. INSERT

  4. ADD NEW

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Correct Option: C

With SQL, how do you select a column named "FirstName" from a table named "Persons"?

sql

  1. EXTRACT FirstName FROM Persons

  2. SELECT FirstName FROM Persons

  3. SELECT Persons.FirstName

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Correct Option: B
Explanation:

To solve this question, the user needs to have a basic understanding of SQL and the syntax used to select specific columns from a table. In SQL, the SELECT statement is used to retrieve data from a database. The user must know how to specify the column name and the table name in the SELECT statement to retrieve the desired data.

Now, let's go through each option and explain why it is right or wrong:

A. EXTRACT FirstName FROM Persons: This option is incorrect. The EXTRACT keyword is used to retrieve date and time information from a specified value, not to select specific columns from a table.

B. SELECT FirstName FROM Persons: This option is correct. The SELECT statement followed by the column name (FirstName) and the table name (Persons) retrieves the data from the specified column in the specified table.

C. SELECT Persons.FirstName: This option is also correct. The SELECT statement can be written in the format of "SELECT TableName.ColumnName" to specify the table name and column name. In this case, the column name (FirstName) is preceded by the table name (Persons) and separated by a dot (.) to retrieve the desired data.

The Answer is: B

With SQL, how do you select all the columns from a table named "Persons"?
sql

  1. SELECT [all] FROM Persons

  2. SELECT All Persons

  3. SELECT *.Persons

  4. SELECT * FROM Persons

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Correct Option: D

With SQL, how do you select all the records from a table named "Persons" where the value of the column "FirstName" is "Peter"?

sql

  1. SELECT [all] FROM Persons WHERE FirstName='Peter'

  2. SELECT * FROM Persons WHERE FirstName LIKE 'Peter'

  3. SELECT [all] FROM Persons WHERE FirstName LIKE 'Peter'

  4. SELECT * FROM Persons WHERE FirstName='Peter'

Show answer
Correct Option: D

AI Explanation

To select all the records from a table named "Persons" where the value of the column "FirstName" is "Peter", you would use the following SQL query:

D. SELECT * FROM Persons WHERE FirstName='Peter'

Let's go through each option to understand why it is correct or incorrect:

Option A) SELECT [all] FROM Persons WHERE FirstName='Peter' This option is incorrect because the keyword "all" is not needed to select all records. The asterisk (*) symbol is used to select all columns.

Option B) SELECT * FROM Persons WHERE FirstName LIKE 'Peter' This option is incorrect because the "LIKE" keyword is used for pattern matching, not for exact matches. In this case, we need an exact match, so the "=" operator should be used instead of "LIKE".

Option C) SELECT [all] FROM Persons WHERE FirstName LIKE 'Peter' Similar to Option A, this option is incorrect because the keyword "all" is not needed to select all records. The asterisk (*) symbol is used to select all columns.

Option D) SELECT * FROM Persons WHERE FirstName='Peter' This option is correct because it selects all columns (*) from the "Persons" table where the value of the "FirstName" column is exactly "Peter".

The correct answer is D.

With SQL, how do you select all the records from a table named "Persons" where the value of the column "FirstName" starts with an "a"?

sql

  1. SELECT * FROM Persons WHERE FirstName='%a%'

  2. SELECT * FROM Persons WHERE FirstName LIKE '%a'

  3. SELECT * FROM Persons WHERE FirstName='a'

  4. SELECT * FROM Persons WHERE FirstName LIKE 'a%'

  5. SELECT * FROM Persons WHERE FirstName='a'"

Show answer
Correct Option: D

AI Explanation

To select all the records from a table named "Persons" where the value of the column "FirstName" starts with an "a", you can use the LIKE operator with the 'a%' pattern.

Let's go through each option to understand why it is correct or incorrect:

Option A) SELECT * FROM Persons WHERE FirstName='%a%' - This option is incorrect because the '%' wildcard should be placed at the end of the pattern to match any characters after 'a'.

Option B) SELECT * FROM Persons WHERE FirstName LIKE '%a' - This option is incorrect because the '%' wildcard should be placed at the beginning of the pattern to match any characters before 'a'.

Option C) SELECT * FROM Persons WHERE FirstName='a' - This option is incorrect because it only selects the records where the FirstName column has the exact value of 'a', not the ones that start with 'a'.

Option D) SELECT * FROM Persons WHERE FirstName LIKE 'a%' - This option is correct because it uses the '%' wildcard at the end of the pattern to match any characters after 'a', effectively selecting all the records where the FirstName column starts with 'a'.

Option E) SELECT * FROM Persons WHERE FirstName='a'" - This option is incorrect because it only selects the records where the FirstName column has the exact value of 'a', not the ones that start with 'a'.

The correct answer is Option D. This option is correct because it uses the LIKE operator with the 'a%' pattern to select all the records where the value of the column "FirstName" starts with an "a".

The OR operator displays a record if ANY conditions listed are true. The AND operator displays a record if ALL of the conditions listed are true

sql

  1. True

  2. False

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Correct Option: A

AI Explanation

To answer this question, let's go through each option to understand why it is correct or incorrect:

Option A) True - This option is correct because the OR operator displays a record if ANY of the conditions listed are true. In other words, if at least one of the conditions is true, the record will be displayed.

Option B) False - This option is incorrect because it contradicts the definition of the OR operator. The OR operator does not require all conditions to be true; it only requires at least one condition to be true.

The correct answer is A) True. This option is correct because it accurately describes the behavior of the OR operator.