Data | MCQs

Explanation

• Communication with MySQL is established through network calls.
• MySQL is a client-server system, where clients communicate with the server over a network connection.
• This communication involves sending queries, commands, and receiving responses over the network.

Explanation

The operator that tests column for the absence of data is an is NULL operator. The NULL operator is used in the database for representing that a particular field is empty.

SELECT ‘column_name’

FROM ‘table_name’

WHERE ‘column_name’ IS NULL

Explanation

A scatter plot is a type of graph used in Exploratory Data Analysis (EDA) to visualize the relationship between two continuous variables. It displays the data points as points on a coordinate grid, with the x-axis representing one variable and the y-axis representing the other.

The primary purpose of a scatter plot is to:

• Show the strength and direction of the relationship between the two variables
• Identify patterns, correlations, or outliers in the data
• Help identify potential relationships that may not be immediately apparent from looking at individual variables

Scatter plots are particularly useful for:

• Identifying linear or non-linear relationships
• Identifying clusters or groups in the data
• Identifying outliers or anomalies

Explanation

MySQL, Microsoft Access, IBM DB2 are database management systems while Google is a search engine.

Explanation

• A data mart is a subset of a data warehouse that is focused on a specific functional area or department, such as marketing, sales, or finance.
• It contains a subset of the data warehouse's data, but is designed to be more accessible and user-friendly for a specific group of users.

Explanation

• The `--log-bin-index` option is used to enable the binary log index file in MySQL.
• This option allows you to specify the name of the index file that stores the binary log file names.

Explanation

A data pipeline is a series of processes that extract data from multiple sources, transform the data into a standardized format, and load it into a target system for analysis.

The primary purpose of a data pipeline in data modeling is to prepare and transform data for analysis, making it possible to:

• Extract data from various sources
• Clean and preprocess the data
• Transform the data into a format suitable for analysis
• Load the data into a data warehouse or analytics platform

Explanation

• The 'CREATE TABLESPACE' privilege allows users to create tablespaces at the server level.
• Tablespaces are used for managing the physical storage of tables and indexes.
• This privilege falls under the realm of server administration.

Explanation

The SERIALIZABLE isolation level is the strictest transaction isolation level provided by SQL Server. It ensures that transactions are executed in a serialized manner, as if they were the only transaction operating on the database. This means that:

• No other transactions can modify data being read by a transaction.
• No other transactions can insert new data that would affect the results of a transaction.
• No other transactions can delete data that a transaction is using.

Explanation

163.23 is a decimal number, which represents a floating-point number (Float) in programming and mathematics.