Introduction to SQL

SQL provides a standard way to create, read, update, and delete data, as well as to manage the database structure and configuration.

Commands like CREATE TABLE, ALTER TABLE, and DROP TABLE are used to create, modify, and delete database objects.

The SELECT statement is used to retrieve data from one or more tables based on specific criteria.

<p>The <code>WHERE</code> clause is used to filter data based on specific criteria.</p> Signup and view all the answers

<p>The <code>JOIN</code> clause is used to combine data from multiple tables based on related columns.</p> Signup and view all the answers

<p>The four primary operations are create, read, update, and delete (CRUD).</p> Signup and view all the answers

<p>To filter data based on a specific condition</p> Signup and view all the answers

<p><code>SELECT column1, column2,...FROM table_name ORDER BY column ASC|DESC;</code></p> Signup and view all the answers

<p>Using the <code>INSERT INTO</code> statement</p> Signup and view all the answers

<p>To ensure data integrity by completing a series of operations as a single unit.</p> Signup and view all the answers

<p>To ensure data integrity and enforce business rules.</p> Signup and view all the answers

<p>To modify existing data in a table</p> Signup and view all the answers

<p>To remove records from a table</p> Signup and view all the answers

<p>To simplify complex queries and provide data abstraction.</p> Signup and view all the answers

<p>To perform aggregate functions on a dataset</p> Signup and view all the answers

<p>To encapsulate complex logic and execute it on the database server.</p> Signup and view all the answers

<p>To retrieve data from one or more tables in a database.</p> Signup and view all the answers

<p>To retrieve data from multiple related tables</p> Signup and view all the answers

<p>The process of organizing data to minimize redundancy and ensure data integrity</p> Signup and view all the answers

<p>To filter data based on a specified condition or criteria.</p> Signup and view all the answers

<p>To sort the resulting data in ascending or descending order.</p> Signup and view all the answers

<p>Avoiding data redundancy, improving data integrity, simplifying data maintenance, optimizing query performance, and facilitating scalability</p> Signup and view all the answers

<p>To group rows that have the same values into summary rows.</p> Signup and view all the answers

<p>To optimize performance, ensure data integrity, and facilitate data management</p> Signup and view all the answers

<p>To combine rows from two or more tables based on a related column between them.</p> Signup and view all the answers

<p>To interact with relational databases in a standardized and efficient manner.</p> Signup and view all the answers

<p>Normalizing a database eliminates redundancy, reduces the likelihood of data anomalies, and improves data integrity and efficiency by breaking down data into smaller, related tables.</p> Signup and view all the answers

<p>Choosing the appropriate data type for each column ensures efficient storage, reduces storage space, and improves data integrity.</p> Signup and view all the answers

<p>Foreign keys establish relationships between tables, enforcing data integrity and maintaining consistency by ensuring referential integrity and preventing data anomalies.</p> Signup and view all the answers

<p>Indexing improves query performance by allowing the database to quickly locate and retrieve data, reducing the time it takes to execute queries.</p> Signup and view all the answers

<p>Normalization improves data integrity but can negatively impact performance, while denormalization optimizes query performance but can compromise data integrity; a balance must be struck based on application requirements.</p> Signup and view all the answers

<p>Regular maintenance tasks, such as updating statistics and reorganizing indexes, ensure the database remains efficient, responsive, and healthy, preventing performance degradation and data corruption.</p> Signup and view all the answers