Retrieving Data from Database using TRC, DRC, SQL, and RA

Introduction
Retrieving data from a database involves using different techniques and languages. In this case, we have four options: TRC, DRC, SQL, and RA. We need to determine which of these options have the same power regarding queries.

Explanation
To understand which options have the same power regarding queries, we need to analyze each one individually.

1. TRC (Tuple Relational Calculus)
- TRC is a non-procedural query language based on mathematical logic.
- It uses variables and quantifiers to express queries over relations.
- TRC focuses on what data should be retrieved, rather than how to retrieve it.
- It has the same power as SQL and RA in terms of expressing queries.

2. DRC (Domain Relational Calculus)
- DRC is another non-procedural query language based on mathematical logic.
- It uses variables and quantifiers to express queries over attributes or domains.
- DRC is more expressive than TRC, as it allows queries involving complex conditions.
- DRC has the same power as SQL and RA in terms of expressing queries.

3. SQL (Structured Query Language)
- SQL is a standard language for managing relational databases.
- It allows users to define, manipulate, and query the data stored in a database.
- SQL provides a rich set of operators and functions for retrieving data.
- SQL has the same power as TRC, DRC, and RA in terms of expressing queries.

4. RA (Relational Algebra)
- RA is a procedural query language that operates on relations.
- It provides a set of operators like selection, projection, join, and union to manipulate relations.
- RA is a foundation for many query languages, including SQL.
- RA has the same power as TRC, DRC, and SQL in terms of expressing queries.

Summary
Based on the explanations above, we can conclude that options TRC, DRC, SQL, and RA have the same power regarding queries. All of them can express queries with similar complexity and retrieve data from a database effectively. Therefore, the correct answer is options A, B, and D.