1.
What is SQL Used For?
Structured Query Language (SQL) is a standard query language used in database management systems. To the question What is SQL, the answer can be given as “Structured Query Language.” This article covers everything you need to know about SQL, which enables the creation, modification, deletion, and querying of data on relational databases.
SQL is the primary tool for managing, organizing, and querying data within a database. Its core function is to communicate with relational databases and perform operations on data. More specifically, to the question What is SQL used for, the following answers can be given:
- SQL is used to store data. For example, registering a new customer into the system.
- It allows querying data, meaning retrieving the information you need. For example, viewing the entire customer list.
- It enables updating existing records. For example, updating a customer’s phone number.
- It allows deleting unused or incorrect records.
- It manages database structures, such as creating new tables, modifying existing ones, or deleting them.
- It allows defining who has access to which data.
2.
What Can Be Done with SQL?
To understand what can be done with SQL, it is necessary to understand how SQL works. The working principle of SQL is as follows: The user or application writes SQL commands. These commands are sent to the database management system (DBMS – e.g., MySQL, Oracle, PostgreSQL). The DBMS processes the commands, retrieves or modifies the appropriate data, and returns the results. The workflow of SQL can be summarized as Command Submission → Query Parsing → Optimization → Result Return. So, what can be done with SQL?
- Customer information management (CRM) can be done. For example, a bank or an e-commerce site can filter and target campaigns for customers in Istanbul.
- Sales reports can be generated. Companies can easily report sales performance using SQL. For example, they can view the total sales for the past month.
- Inventory tracking can be performed; retail chains or warehouses can monitor critical products. For instance, listing items with fewer than 10 units in stock.
- User behavior analysis can be conducted. Platforms such as Instagram and X can analyze user activities using SQL Server.
- Financial transactions can be executed. For instance, banks use SQL to manage secure money transfers.
- Employee management can be handled. HR departments can manage personnel data with SQL. For example, listing employees with salaries exceeding 50,000 TL.
- It can be used for authorization and security. For instance, granting a user only read access.
As seen, SQL enables data querying, reporting, updating, security management, financial transactions, inventory tracking, and customer data management. Essentially, every application and business with underlying data (banking, social media, e-commerce, healthcare systems) benefits from SQL. How about leveraging GlassHouse database services to provide the most suitable database technologies for your IT infrastructure in the environment you want, fully managed?
3.
What Are SQL Commands?
SQL commands are basic instructions used to interact with a database. They are categorized by functionality as follows:
- Data Definition Language (DDL): Used to define or modify database structures. For example, the CREATE command creates a new database or table. The ALTER command modifies the structure of an existing table. The DROP DATABASE command deletes an entire database, while DROP TABLE deletes a specific table. The TRUNCATE command removes all data from a table without deleting the table itself.
- Data Manipulation Language (DML): Used to perform operations on the data in tables. For example, the INSERT command adds new records. The UPDATE command modifies existing records. The DELETE command removes selected records.
- Data Query Language (DQL): Used to query data. The SELECT command retrieves data from tables.
- Data Control Language (DCL): Used for user authorization and security. The GRANT command assigns permissions to a user. The REVOKE command removes permissions from a user.
- Transaction Control Language (TCL): Ensures the integrity, consistency, isolation, and durability of database transactions; managed by commands such as COMMIT (to approve changes), ROLLBACK (to undo changes), and SAVEPOINT (to set intermediate control points).
In conclusion, SQL is a critical tool that enables applications and organizations to manage their data in an organized, secure, and accessible manner. From daily operations such as customer information, sales reports, inventory tracking, and financial transactions to long-term strategic decision-making, SQL makes accessing accurate and timely information possible. With SQL, companies not only store their data but also analyze it to gain a competitive edge. Offering security, speed, and flexibility, SQL is indispensable for businesses aiming to make data-driven decisions in the digital era. Learn more about digital transformation in businesses here!
