- In this project, I’m working on various database management tasks using SQL. My tasks include creating and managing tables, inserting and manipulating data, and executing complex queries to retrieve and analyze information. I'll be combining data from different tables, performing union operations, filtering and grouping results, and joining tables to extract meaningful insights. Additionally, I'll be altering table structures, updating data, and solving problems related to data availability.
- Creating and Managing Tables: I need to create several tables, such as CUSTOMER, CUSTOMER_2, and INVOICE, specifying the columns and data types. After that, I’ll insert data into these tables.
- Executing SQL Queries:
- Union Operations: I’ll combine results from different tables using UNION ALL to include duplicates and UNION to exclude duplicates.
- Filtering and Grouping: I’ll filter results based on specific conditions, group data, and use aggregate functions like COUNT and AVG. -J oining Tables: I’ll perform inner joins to retrieve related data from multiple tables, such as linking customer information with their invoices.
- Advanced SQL Queries: I’ll run more complex queries, including subqueries, to extract specific information or perform calculations.
- Table Alteration: I’ll add new columns to existing tables and update them with calculated values.
- Problem-Solving: Some questions ask me to reason about the feasibility of certain queries based on the data available in the tables. For example, if the required data, like hire dates, isn’t present, I’ll need to explain why the query isn’t possible.