- Increment: On-Call –
- How does the SQL Server Query Optimizer Works – blog x – direction obsessed – At the core of the SQL Server Database Engine are two major components: the Storage Engine and the Query Processor, also called the Relational Engine.
Storage Engine: takes care of reading data between the disk and memory in a manner that optimizes concurrency while maintaining data integrity
Query Processor: 1. takes care of devising a query plan (what algorithms/operators to implement) by Query Optimizer 2. execute the query according to that plan by Execution Engine
- Understanding how SQL Server executes a query – If you are a developer writing applications that use SQL Server and you are wondering what exactly happens when you ‘run’ a query from your application, I hope this article will help you write better database code and will help you get started when you have to investigate performance problems.
- BI: Beer Intelligence? · The “Select ALL” parameter option [SSRS] – You all know that report parameters can be populated through a query, right? And multi-value parameters get this magical (Select All) item as first one in the dropdown list. I used the word magical in the previous sentence because this (Select All) item is not a real one. It’s a bit like a fata morgana: you can click it but it doesn’t really get selected. It only appears that way in the dropdown. But you can’t write an expression that tests if the (Select All) item is selected because it doesn’t really exist in the array. The only thing it does is it selects all items when it gets clicked.
- Set Select All as Default for Multi-Value Report Parameters in SQL Server Reporting Services – Most SQL Server Reporting Services (SSRS) reports contain multi-value report parameters and sometimes there be a requirement to set "Select All" as the default. There is not a simple way to set "Select All" as the default for an SSRS report, but in this tip I will demonstrate how to set "Select All" as the default parameter value.
- Unlearning descriptive statistics | Hacker News –
- DECLARE @local_variable (Transact-SQL) | Microsoft Docs – Variables are declared in the body of a batch or procedure with the DECLARE statement and are assigned values by using either a SET or SELECT statement. Cursor variables can be declared with this statement and used with other cursor-related statements. After declaration, all variables are initialized as NULL, unless a value is provided as part of the declaration.
- Table Variables In T-SQL –