Podcast
Questions and Answers
What is the primary purpose of a primary key in a relational database table?
What is the primary purpose of a primary key in a relational database table?
- Sorting data alphabetically
- Defining table relationships
- Creating backup copies
- Ensuring data uniqueness (correct)
In a relational database, which of the following is NOT a key concept?
In a relational database, which of the following is NOT a key concept?
- Array (correct)
- Tuple
- Table
- Attribute
Which SQL command is used to delete a table from a database?
Which SQL command is used to delete a table from a database?
- DROP TABLE (correct)
- ERASE TABLE
- REMOVE TABLE
- DELETE TABLE
In a relational database, what is the purpose of the primary key?
In a relational database, what is the purpose of the primary key?
Which SQL command is used to modify existing data in a table?
Which SQL command is used to modify existing data in a table?
What does the WHERE clause in an SQL query specify?
What does the WHERE clause in an SQL query specify?
In a relational database, what is the primary purpose of a primary key?
In a relational database, what is the primary purpose of a primary key?
Which SQL command is specifically used to create a new table in a relational database?
Which SQL command is specifically used to create a new table in a relational database?
What does SQL stand for in the context of relational databases?
What does SQL stand for in the context of relational databases?
In a relational database, what happens when a foreign key is used?
In a relational database, what happens when a foreign key is used?
Study Notes
Primary Key in Relational Databases
- Serves as a unique identifier for each record in a table, ensuring that no duplicate entries exist.
- Provides a way to establish and enforce referential integrity within the database.
Key Concepts in Relational Databases
- Concepts typically include tables, rows, columns, primary keys, foreign keys, indices, and relationships. Items not fitting these categories may include non-relational structures.
SQL Commands for Table Management
- The command
DROP TABLEis used to delete a table from a database permanently. - To create a new table, the
CREATE TABLEcommand is utilized, defining the table structure and fields.
Modifying Data in a Table
- The SQL command
UPDATEis employed to modify existing data within a specified table.
WHERE Clause in SQL Queries
- The
WHEREclause filters records to specify which rows should be retrieved or affected, based on certain criteria.
Foreign Key Functionality
- A foreign key creates a link between two tables, establishing a relationship that allows for cross-referencing data, while enforcing referential integrity.
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Description
Test your knowledge about relational databases, primary keys, and DBMS models with this quiz. Determine the correct definitions and concepts related to database structures and relationships.
