SQL Server - Query to return list of tables and the space they use on disk

Below is a useful MS SQL Server query I use to get the list of database tables and information on how much disk space they use. The results are ordered by the size on disk descending.

SELECT 
    t.NAME AS TableName,
    s.Name AS SchemaName,
    p.rows AS RowCounts,
    CAST(ROUND(((SUM(a.total_pages) * 8.0) / 1024), 2) AS DECIMAL(18,2)) AS TotalSpaceMB,
    CAST(ROUND(((SUM(a.used_pages) * 8.0) / 1024), 2) AS DECIMAL(18,2)) AS UsedSpaceMB,
    CAST(ROUND(((SUM(a.data_pages) * 8.0) / 1024), 2) AS DECIMAL(18,2)) AS DataSpaceMB
FROM 
    sys.tables t
INNER JOIN      
    sys.indexes i ON t.OBJECT_ID = i.object_id
INNER JOIN 
    sys.partitions p ON i.object_id = p.OBJECT_ID AND i.index_id = p.index_id
INNER JOIN 
    sys.allocation_units a ON p.partition_id = a.container_id
LEFT OUTER JOIN 
    sys.schemas s ON t.schema_id = s.schema_id
WHERE 
    t.is_ms_shipped = 0
GROUP BY 
    t.Name, s.Name, p.Rows
ORDER BY 
    TotalSpaceMB DESC;

When to pass a dependency to a class?

I was speaking to another developer the other day and he insisted that if a class needs an instance of another class it should always be passed in an 'Init' method and not in the constructor. I disagreed with him on this and thought I should clarify when I think a dependency should be passed.

There are 2 options when passing a dependency to a class:

1. Passing it as a parameter in the Create constructor.
2. Passing it in a separate 'Init' method after creation. It does not have to be called 'Init'. 

When to use the 'Create' method and its advantages:

• When the class absolutely needs the other class to operate properly.
• Ensures the object is in a valid state immediately after creation.
• Prevents accidental use of an uninitialized object.
• Simplicity, it can lead to cleaner and more concise code.

When to use an 'Init' method and its advantages:

• When the dependency could be seen as optional. The class can operate or partly operate without the other class. This can be done with the Create method, but passing it as nil.
• Need delayed initialization.   

In most cases, the Create method (constructor) approach is preferred for better safety and reliability.

Should you write a website using Delphi?

Over the years I've written various websites some of which used Delphi to publish the pages. This method used HTML templates, JS and CSS files and the data from the database to stitched them together to produce the pages. The question is if I was to write a website from scratch would I still use this method or would I look at using a Javascript framework like ReactJS, Angular or Svelte? 

I'm sure the answer to this question would depend on the spec for the website, but here are some advantages and disadvantages of writing a website using Delphi.

Advantages:

• If you have existing applications written in Delphi you can use existing code like common functions, classes and units that relate to your business, so there is no need to rewrite code in another language.
• Time to develop the site could be shorter than using a framework like ReactJS, especially if you need to learn a new language.
• Possible to implement JS libraries like Bootstrap.
• Have front and backend code in the same project. Have a single service that is responsible for retrieving data from the database then using that data to produce the front end page.

Disadvantages:

• You still have to write code in HTML, JS and CSS.
• Compared to popular web development languages, Delphi lacks a vibrant ecosystem of web-specific tools, libraries, and frameworks.
• Testing changes while developing is slow compared to other languages like ReactJS, which automatically refreshes the page you are viewing when you save a change.
• Modern web development frameworks often come with built-in security measures (e.g., CSRF protection, SQL injection prevention). In Delphi, many of these must be implemented manually, increasing the risk of vulnerabilities.
• Delphi's future as a web development platform is uncertain compared to the robust growth of modern web development languages.
• Difficult to find Delphi developers, especially ones with web site development experience.
• A lack of beginner-friendly tutorials, guides, and resources for web development in Delphi can make onboarding new developers more difficult.

In Conclusion:

While Delphi has its strengths, its disadvantages for web development primarily revolve around the lack of modern web development focus, limited developer availability, higher costs, and the complexity of implementing web-specific features. For teams already invested in Delphi or needing tight integration with Delphi-based systems, it can be a viable option, but for new projects or those targeting modern web standards, other technologies may be more practical.

Below is a table from ChatGPT with some security vulnerabilities & considerations: