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Welcome to our blog post that will introduce you to the core basics of SQL Server, perfect for anyone just starting down the path of learning SQL. Structured Query Language (SQL) is a standard language for accessing and manipulating databases. SQL Server is a relational database management system (RDBMS) developed by Microsoft designed to manage and retrieve information efficiently.
What is SQL?
SQL, or Structured Query Language, is a standardized programming language that is used to manage relational databases and perform various operations on the data in them. It is particularly effective in handling structured data, i.e., data incorporating relations among entities and variables.
Writing your First SQL Query
SQL queries are used to fetch data from your database. They are the most common operations that a typical data analyst or data scientist performs on a daily basis. Here is a basic example of SQL code that fetches all the data from a table:
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SELECT * FROM TableName; |
In this code, ‘SELECT *’ is used to select all data. ‘FROM’ keyword is used to specify the table from which we want to fetch the data, in this case ‘TableName’.
Limiting Result Set
What if you want to see the information of a specific row or a limited number of rows? Instead of the ‘*’ symbol, you can specify the column’s name you are interested in. And if you want to limit the number of results, you can use the ‘TOP’ keyword accompanied by the number of rows you wish to fetch:
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SELECT TOP 3 column1, column2 FROM TableName; |
The script above will return the top 3 rows from column1 and column2 from the table ‘TableName’.
Filtering Results
You may want to view specific data in your SQL Server database. In order to do this, you can use a ‘WHERE’ clause in your query.
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SELECT * FROM TableName WHERE ColumnName = 'Value'; |
In the code above, all data from the table ‘TableName’ will be fetched where ‘ColumnName’ equals ‘Value’.
And that covers some of the SQL basics! Keep in mind that SQL is a vast field and it takes time to learn all its specialties. Start by practicing these basic commands and soon enough, you’ll be able to navigate through databases with ease. Happy Learning!