KB: SQL openquery vs linked server

Good read: Openquery vs Linked Server

 

The linked server query, SQL Server is going to make decisions for you on how it mashes all the data together and returns the result set. By default, when you run a distributed query using a linked server, the query is processed locally. This may or may not be efficient, depending on how much data must be sent from the remote server to the local server for processing. Sometimes it is more efficient to pass through the query so that it is run on the remote server. This way, if the query must process many rows, it can process them on the remote server, and only return to the local server the results of the query. The OPENQUERY function is used to specify that a distributed query be processed on the remote server instead of the local server.


The alternative to using Linked Servers is to use the OPENQUERY statement, also known as a pass through query. When using an OPENQUERY statement, the WHERE clause gets executed at the remote server and the resultant (mapped) records traverse over the wire instead of an entire sourced data set. The only issue with the OPENQUERY statement is that the TSQL syntax is limited in that it does not accept variables for arguments. To get around this, you need to ensure that the OPENQUERY TSQL syntax is generically coded.


Reference:


Comments

Post a Comment

Popular posts from this blog

KB: Azure ACA Container fails to start (no User Assigned or Delegated Managed Identity found for specified ClientId)

Image
When deploying secure workloads using Azure Container Apps (ACA) , teams often face confusion between User Assigned Managed Identities (UAMI) and App Registrations . While both entities are visible in Azure Active Directory and have similar identifiers (Application ID, Object ID), they serve very different purposes . This confusion can lead to authentication failures when accessing services like Azure App Configuration or Key Vault . A common issue occurs when a container app is configured with a managed identity, but the environment variables or role assignments mistakenly reference an App Registration instead, causing errors like: "No User Assigned or Delegated Managed Identity found for specified ClientId" This article breaks down the difference between UAMI and App Registrations, explains why this issue happens, and outlines the correct approach to resolve it. Symptoms Azure Container App fails to authenticate to Azure App Configuration or other services. Logs...
Read more

Electron Process Execution Failure with FSLogix

  Technical Note: Electron Process Execution Failure with FSLogix 1. Overview When running Electron-based applications in environments using FSLogix Profile or Office Containers , users may encounter issues where the Electron process fails to launch or execute properly . This behavior has been observed in Azure Virtual Desktop (AVD) , Windows Virtual Desktop (WVD) , and other environments where FSLogix filter drivers are active. 2. Symptoms Electron-based applications (e.g., desktop apps built on Electron, CLI wrappers) do not start , remain unresponsive, or terminate silently. No visible logs or error messages are generated by the application. Standard executables run correctly when placed outside of the FSLogix-controlled profile path (e.g., copying to C:\Temp allows execution). The issue is reproducible across all Electron apps in the FSLogix-managed profile. 3. Root Cause The issue is linked to FSLogix filter drivers ( frxdrv , frxdrvvt , frxccd ) interfe...
Read more

KB:RMM VS DEX (Remote Monitoring Management vs Digital Employee Experience)

Digital Employee Experience (DEX) and Remote Monitoring and Management (RMM) tools serve different purposes and cater to distinct aspects of IT and employee management. Digital Employee Experience (DEX) Focus: Enhancing the overall experience of employees with their digital workplace tools and environment. Key Features: User Experience Monitoring: Tracks how employees interact with software and hardware, identifying issues impacting productivity. Performance Analytics: Provides insights into the performance of applications from the end-user's perspective. Feedback Mechanisms: Allows employees to report issues and give feedback on their digital tools and environment. Employee Well-being: Monitors factors that affect employee satisfaction and well-being, such as system performance and usability. Proactive Support: Identifies potential issues before they become significant problems, enabling proactive IT support. Goals: Improve employee satisfaction and productivity. Ensure a sm...
Read more