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Whether you’re an aspiring data analyst, a software developer, or just someone interested in managing data for your small business, learning SQL, or Structured Query Language, is a step in the right direction. In this article, we will reroute your journey through SQL basics and its application in database management. Keep your coding gears ready as we’ve got practical SQL code examples along the way.
What is SQL?
SQL, an acronym for Structured Query Language, is a standardized language used in programming and designed for managing data held in a relational database management system (RDBMS), or for processing data streams in real-time in a relational data stream management system. It is particularly useful in handling structured data, i.e. data incorporating relations among entities and variables.
Getting Started with SQL
The first step in learning SQL is understanding how data are organized. An SQL database is typically organized into tables. Each table is like a standalone spreadsheet with columns (fields) and rows (records).
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CREATE TABLE Customers ( ID INT PRIMARY KEY, Name VARCHAR (20), Age INT, City VARCHAR (20) ); |
Basic SQL Commands
Here are few basic SQL commands that will you get started:
1. SELECT: Extract data from a database
The SELECT statement is used to select data from a database. The data returned is stored in a result table, called the result-set.
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SELECT * FROM Customers; |
2. UPDATE: Update data in a database
The UPDATE statement is used to modify the existing records in a table.
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UPDATE Customers SET Name = 'John', City = 'New York' WHERE ID = 1; |
3. DELETE: Delete data from a database
The DELETE statement is used to delete existing records in a table.
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DELETE FROM Customers WHERE Name='John'; |
SQL is the backbone behind any data analysis task and a must-have skill for data-driven organizations. Remember, the crux of SQL operations lies in understanding and implementing the right commands to manage and manipulate your data. Happy coding!