Cada pergunta deste Quiz é cronometrada.
The SQL select statement is used to select data from tables. Which of the following is the correct syntax of retrieving all records from all columns in a table called employees?
A) employees.select(all)
B) set select = employees
C) SELECT * FROM employees
If I am concerned about the particular order in which the results from a select statement are returned, which keywords should I use to achieve this?
A) ORDER BY
B) SORT BY
C) ARRANGE BY
I need to retrieve related data from more than one table. Which of these would be required to link the tables when I perform a select operation?
A) JOIN
B) CONNECT
C) MERGE
I have the data and now I need to make a table to store my data. What SQL statement would I use for this?
A) SELECT statement
B) CREATE statement
C) MAKE statement
How can you populate a database table with data using SQL?
A) By using an INSERT statement
B) By using a SELECT
C) By using an ADD statement
I just discovered my table needs an additional column, what should I do to make this change?
A) Delete your table and recreate it
B) There is nothing you can do
C) Use the ALTER TABLE statement
Now that my data is corrupted I want to remove it all from the table. What should I do?
A) use CLEAN
B) use SELECT EMPTY
C) use TRUNCATE
How about if I just want to delete the table, what should I do?
A) You cannot delete tables
B) Use the DROP TABLE statement
C) Use the DELETE statement
How do I set a certain criteria when selecting data from my table?
A) Use FILTER keyword
B) Use the CRITERIA keyword
C) Use the WHERE clause
Sometimes it may be difficult to test whether a column is void of data or has some non printable data. Visually they look the same, how can I verify this using SQL?
A) Use IS NULL or IS NOT NULL clauses
B) Use = ''
C) There is no such thing as empty space in a table
Retrieving data from my table using a SELECT statement is extremely slow, how can I solve this problem?
A) Break your table into several smaller ones
B) Upgrade you computer hardware
C) INDEX your table columns
I have noticed on occasion that I need to place a selection criteria in one statement based on indefinite information stored in another table. Is there an efficient way to go about it? If yes, what should I do?
A) Use a subquery
B) Run the SELECT statement in a loop;
C) There is no efficient way
How do I use SQL to perform math calculations?
A) Use the CALCULATE clause
B) Use the MATH statement
C) Use the SELECT statement
While we are still thinking about calculations, how would I find the average of values in a certain column in SQL?
A) Use SELECT AVERAGE
B) Use AVG() built in function
C) You need a third party application
What if I need to make changes to the data in a database without affecting the table structure, what would I use?
A) Data in a table cannot be edited
B) TRUNCATE the table and INSERT the correct data
C) Use the UPDATE statement
