DMLC

The command to change some records/ rows of a particular column is?

• Change command

• Update command

• modify command

• Alter command

The query to update a field Designation to “Data Scientist” of all records in a table UserDetails is?

• update userdetails set designation = "Data Scientist"

• Modify userdetails set designation = "Data Scientist"

• Alter userdetails set designation = "Data Scientist"

• change userdetails set designation = "Data Scientist"

The query to update a field Designation to “Data Scientist” of all records having Name = ”Julie” in a table UserDetails is?

• update userdetails set designation = "Data Scientist" where Name ="Julie"

• update userdetails to designation = "Data Scientist" where Name ="Julie"

• modify userdetails set designation = "Data Scientist" change Name ="Julie"

• update userdetails set designation = "Data Scientist" change Name ="Julie"

Choose the correct option:

• Update command can be used to modify multiple columns at same time

• Modify command is used to rename the column name

• Update command can be used to modify single column at same time

Lets say we have a table named Users which has fields name, email and phonenumber. Suppose a particular user named “Ashley” has left the portal and we want to remove her record from the table. Which of the following queries will do the required job?

• remove user where name is Ashley

• delete from users where name ="Ashley"

• delete from users where name in ("Ashley")

• remove user from users where name in ("Ashley")

What will the command “delete from Users;” do in MySQL

• It will ask for which users to delete

• it is an incorrect statement it will throw error

• It will delete all rows and make table empty

• It will delete first row

The command to permanently remove data from a table is?

• Select

• Delete

• Ampute

• Purge

Which command can be used to know the structure of a table

• Desc

• Describe

• Structure

• Show database structure

There is an existing table called “players” in the database. You want to add a column to it named “Position” which signifies where the player plays. The command to do so is the?

• Alter

• delete

• select

• bin

Suppose I want to add a column named “Position” to “players” table as in previous question. Position is a string of characters and can have maximum length 20. Which query can be used for this purpose?

• alter table players add column position varchar(20)

• alter table players delete column position varchar(20)

• modify table players add column position varchar(20)

• select table players add column position varchar(20)