Computer Science/IT MCQs
Topic Notes: Computer Science/IT
MCQs and preparation resources for competitive exams, covering important concepts, past papers, and detailed explanations.
Plato
- Biography: Ancient Greek philosopher (427–347 BCE), student of Socrates and teacher of Aristotle, founder of the Academy in Athens.
- Important Ideas:
- Theory of Forms
- Philosopher-King
- Ideal State
81
What does a "Crosstab Query" do?
Answer:
It summarizes data in a spreadsheet-like format, with row headings, column headings, and a calculated value
Crosstab queries are excellent for analysis. For example, you could use one to show total sales (the value) for each product (the row heading) across different years (the column headings).
82
A "Parameter Query" is a query that:
Answer:
Prompts the user for input (a criterion) every time it is run
This makes a query flexible. Instead of hard-coding a specific city, you can create a parameter query that pops up a box asking "Enter City:" each time it runs.
83
Which SQL clause specifies which tables to retrieve data from?
Answer:
FROM
The `FROM` clause lists the table or tables that contain the data you want to query (e.g., `FROM Customers`).
84
Which SQL clause is used to specify the condition for filtering records?
Answer:
WHERE
The `WHERE` clause is the SQL equivalent of the "Criteria" row in the Access design grid. It filters the records based on the specified condition (e.g., `WHERE City = 'London'`).
85
SQL stands for:
Answer:
Structured Query Language
SQL is the standard language for communicating with and managing data in relational databases. Access uses it behind the scenes for all its queries.
86
What does an "Update Query" do?
Answer:
It modifies the data in existing records within a table
An Update Query is used for bulk changes. For example, you could use one to increase the price of all products in a certain category by 10%.
87
Which type of query makes changes to the data in your tables?
Answer:
Action Query
Action Queries are used to modify data. There are four types: Make-Table, Append, Update, and Delete queries.
88
To filter records in a query to show only customers from "London", you would type "London" in the _________ row for the City field.
Answer:
Criteria
The Criteria row in the design grid is where you specify the conditions that records must meet to be included in the query results.
89
In the Query Design View, the top pane shows _________, and the bottom pane (the design grid) shows __________.
Answer:
The tables used in the query, the fields and criteria for the query
The top pane is where you add the tables you want to get data from. The bottom grid is where you build the query by adding fields, setting sort orders, and entering criteria.
90
What is the main purpose of a "Select Query"?
Answer:
To retrieve and view data from one or more tables
A Select Query is the most common type of query. It is used to select a specific subset of data based on criteria you define, without changing the underlying data.