Lesson 1

You will need to use SQL statements to query and modify the database in the VirtualBookShelf.com Web site. This module focuses on how to write some of the most basic queries. When you finish, you will be able to do the following:

1. Use the SQL SELECT statement to retrieve all the rows in a table
2. Modify a SELECT statement to parameterize data search criteria
3. Sort, modify, add, and delete records in a table

Later in the course, you will learn how to use the SQL Query Designer Control for .NET to build advanced queries.

The SQL Query Designer Control was a visual query-building tool that allowed users to create queries using a graphical interface within Visual Studio. However, Microsoft has deprecated and removed this feature from recent versions of Visual Studio and SQL Server Management Studio (SSMS).
Current Status in SQL Server 2022:

• SQL Query Designer still exists in SSMS, but only as a built-in tool, not as a separate .NET control.
• The standalone SQL Query Designer Control for .NET does not exist anymore as part of the Visual Studio toolset.
• Developers now use alternatives such as:
  • TableAdapters and DataSets in Visual Studio.
  • LINQ to SQL or Entity Framework for ORM-based query building.
  • Third-party SQL Query Builder libraries like Active Query Builder or DevExpress SQL Query Builder.

1. How to Access SQL Query Designer in SSMS 2022
Although the SQL Query Designer Control is not available for .NET applications, you can still access the built-in Query Designer in SQL Server Management Studio (SSMS).
Steps to Open the SQL Query Designer in SSMS 2022:

1. Open SQL Server Management Studio (SSMS).
2. Connect to your SQL Server 2022 instance.
3. Open a New Query Window.
4. Click on Query in the menu bar.
5. Select Design Query in Editor.
6. The graphical query designer opens, allowing you to visually build queries.

2. Alternatives to SQL Query Designer Control in .NET
Since the SQL Query Designer Control is no longer part of .NET, developers now use alternative approaches:
A. Using TableAdapters in Visual Studio

1. Add a Dataset (.xsd) file in your Visual Studio project.
2. Configure TableAdapters to generate SQL queries visually.
3. Use TableAdapter.Fill() to execute queries.

B. Using Entity Framework (EF Core)

using (var context = new MyDbContext())
{
    var employees = context.Employees
                           .Where(e => e.Department == "IT")
                           .ToList();
}

Advantages:

• No need for SQL queries.
• Strongly typed queries.
• Works with SQL Server 2022.

C. Using LINQ-to-SQL

var employees = from emp in db.Employees
                where emp.Department == "HR"
                select emp;

Advantages:

• Integrated with C#.
• Easier than writing raw SQL.

D. Using Third-Party Query Builders

• DevExpress Query Builder
• Active Query Builder
• Telerik Reporting Query Builder

These tools provide a visual SQL query designer for modern .NET applications.
Conclusion

• SQL Query Designer Control for .NET no longer exists in Visual Studio or SQL Server 2022.
• You can still use the Query Designer in SSMS for graphical query building.
• For .NET applications, Microsoft now recommends using Entity Framework, LINQ-to-SQL, or TableAdapters.
• Third-party tools like DevExpress Query Builder can serve as an alternative for a graphical query designer in .NET.

A database is one or more large structured sets of persistent data, usually associated with software to update and query the data. A simple database might be a single file containing many records, each of which contains the same set of fields where each field is a certain fixed width. Breaking this definition down into something more manageable, first it says that a database consists of structured sets of data, which means that a database contains collections of data. For example, the database might contain the details of relational database design or data about all the books in a library. You probably would not want to mix these two collections of data, or else when you want to find data about a book you would have to look through irrelevant data on golf scores. In short, databases help you organize your data. A database stores its collections of data in tables.
The definition goes on to say that databases are usually associated with software that allows the data to be updated and queried. Real-life examples of database software include Microsoft's Access, Oracle's 11g, IBM's DB2, MySQL, and Microsoft's SQL Server 2012. Often these programs are referred to as databases, but strictly speaking, they are database management systems (DBMS). A database is the sets (collections of related data) grouped into one entity. You could, for example, create an Access database, call it MyDatabase, include various data collections inside that one database, and manage the whole thing with the MS Access software.

A database is one or more large, structured sets of persistent data, typically managed by software that allows for updating and querying the data. Here's a step-by-step breakdown:

1. Structured Sets of Data:
   • A database is made up of organized collections of data. "Structured" means the data is arranged in a specific, predictable format or pattern, making it easier to store, retrieve, and manage.
   • These collections could be tables, files, or other data structures, depending on the type of database.
2. Persistent Data:
   • The data in a database is "persistent," meaning it is stored long-term and remains available even after the program or system that created it is closed or restarted. This distinguishes databases from temporary, in-memory data.
3. Associated Software:
   • Databases are usually managed by software (e.g., a Database Management System, or DBMS) that provides tools and functionality to:
   • Update the data (e.g., insert, modify, or delete records).
   • Query the data (e.g., search or retrieve specific information based on criteria).
4. Simple Database Example:
   • A simple database could be a single file containing multiple records.
   • Each record represents a single entry or row of data.
   • Each record contains the same set of fields (e.g., columns or attributes like "Name," "Age," "Address").
   • Each field has a fixed width or predefined format, ensuring consistency across all records.

A database contains collections of data (structured sets), and these collections are organized in a way that makes the data persistent, accessible, and manageable through software for updates and queries. Your understanding aligns well with the definition!
In the next lesson, SELECT statements that retrieve all rows from a single table will be written.