Fix integer division in T-SQL percentages from COUNT, SUM and window calculations with decimal types and rounding at the right step.
Logins and Users in SQL Server: Who Gets In and What They Can Do
Logins and users are two different things in SQL Server. A login gets a person or an application into the server, and a user gets them into one database. This post explains Windows and SQL authentication, how a login maps to a user, and how to check the mapping with a query.
What Are Filegroups in SQL Server and When to Use Them
What are filegroups in SQL Server? A filegroup is a named container for data files, and an ordinary table or index lives in exactly one. This post builds a small demo, shows where a table lands, and gives honest advice on when extra filegroups help and when they only add work.
Data Files and Log Files: What Each One Does in SQL Server
Data Files and Log Files are the two kinds of file every SQL Server database needs. This post explains what lives in each, why the log is written first, and how to list both with a query on sys.database_files.
What Is a Foreign Key, and What It Protects
What is a foreign key? It’s a column that must match a key in another table, and SQL Server refuses any value that has no match. This post shows the error it raises, the ON DELETE options, and why the foreign key column needs an index of its own.
SQL Code Generators: Let SSMS Write the Script for You
SQL Code Generators in SSMS turn clicks into T-SQL. This post shows the Script button on dialogs, the Generate Scripts wizard and Select Top 1000 Rows, plus the checks I run before I trust a generated script.
Using Management Studio: A First Tour of SSMS 22
Using Management Studio gets easier once you know where to look. This first tour of SSMS 22 covers the connection dialog, Object Explorer, the query window, running a query, reading the results and saving a .sql file, with one small demo script to follow along.