About Lesson
Exploratory Data Analysis (EDA) using MySQL is a powerful technique to uncover insights and patterns within your dataset. By combining SQL queries with statistical functions and data visualization tools, you can gain a deeper understanding of your data.
Key Steps in MySQL EDA:
-
Data Cleaning and Preparation:
- Handle Missing Values: Identify and address missing values using techniques like imputation or removal.
- Data Type Conversion: Ensure data types are correct for analysis (e.g., converting text to numeric).
- Outlier Detection and Handling: Identify and handle outliers using statistical methods or domain knowledge.
-
Univariate Analysis:
- Descriptive Statistics: Calculate measures like mean, median, mode, standard deviation, and quartiles.
- Data Distribution: Visualize data distribution using histograms, box plots, and density plots.
- Frequency Analysis: Analyze the frequency of categorical variables.
-
Bivariate Analysis:
- Correlation Analysis: Measure the strength and direction of relationships between numerical variables.
- Contingency Tables: Analyze the relationship between categorical variables.
- Scatter Plots: Visualize the relationship between two numerical variables.
-
Multivariate Analysis:
- Cluster Analysis: Group similar data points together.
- Principal Component Analysis (PCA): Reduce the dimensionality of data.
SQL Functions for EDA:
- Aggregation Functions:
COUNT
,SUM
,AVG
,MIN
,MAX
- Statistical Functions:
STDDEV
,VARIANCE
,COVARIANCE
- String Functions:
LENGTH
,CONCAT
,SUBSTRING
- Date and Time Functions:
CURDATE
,CURTIME
,DATE_ADD
,DATE_DIFF
- Window Functions:
RANK
,DENSE_RANK
,ROW_NUMBER
,LEAD
,LAG
Tools for Visualization:
- MySQL Workbench: Built-in visualization capabilities.
- Python Libraries: Pandas, NumPy, Matplotlib, Seaborn.
- R: ggplot2, dplyr.
By effectively utilizing SQL and visualization tools, you can extract valuable insights from your data, make informed decisions, and drive data-driven actions.