Category: T-SQL Fundamentals

  • Get Current Date & Time in SQL Server

    Getting the current date and time in SQL Server is straightforward. Choosing the correct function for your workload is what matters. Whether you’re stamping audit rows, logging ETL runs, or investigating production issues, SQL Server exposes several built-in functions with different precision and return types. All of these functions use the Windows OS clock of…

  • How to Kill a SPID in SQL Server

    In SQL Server, every connection to the database engine is assigned a Session Process ID, commonly known as a SPID. There are situations where you may need to kill a SPID in SQL Server. This typically occurs when a session is blocking other queries, running indefinitely, holding locks during maintenance, or preventing a database from…

  • How to Add Columns to Tables in SQL Server

    Adding columns to tables in SQL Server is a routine task, but it is not always a harmless one. On small tables it is trivial. On large or business-critical tables — especially those involved in replication or heavy write workloads — it can introduce blocking, transaction log growth, or downstream latency if handled carelessly. This…

  • Kill All User Sessions on a Database in SQL Server

    When you need to drop, restore, or change database settings, active user sessions often get in the way. SQL Server will block these operations until all connections are cleared. In busy environments, waiting is rarely practical. This post shows a safe, deliberate, and review-first way to identify and kill all user sessions connected to a…

  • Deleting Rows in Batches in SQL Server

    Deleting large volumes of data from a SQL Server table looks simple, but it can cause real problems if done carelessly. A single large DELETE can: When you’re cleaning up historical data or running routine maintenance, deleting rows in batches is usually the safest and most predictable approach. This post shows a simple, production-safe pattern…

  • What the USE Command Does in SQL Server

    The USE command changes the database context for the current session. Every statement in SQL Server runs in the context of a database. When you run USE, you are telling SQL Server which database subsequent statements should execute against until the context changes again or the session ends. That single behaviour explains a lot of…