Mastering Data Queries in SQL Server: From Basic Selection to Subqueries
Core DQL Operations
SQL Server provides powerful data retrieval capabilities through DQL (Data Query Language). This guide covers essential query techniques using a teaching management system database scenario.
Database Context
The teaching information management system includes four main tables:
tblStudents — student information (StudentID, S ...
Posted on Sun, 17 May 2026 23:30:13 +0000 by d99kg
Efficient Pagination and Window Functions in SQL Server
Paginatoin with Separate Count Query
When implementing pagination in SQL Server, one common approach is to execute two separate queries—one to retrieve the total record count and another to fetch the actual data page.
-- Retrieve total number of matching records
SELECT COUNT(*) AS TotalRecords
FROM Products
WHERE CategoryId = 5 AND IsActive = 1 ...
Posted on Sun, 17 May 2026 03:50:15 +0000 by Code_guy
Batch Processing Excel Files and Importing Data into SQL Server with Python
Requirements Analysis
Excel data porcessing typically involves:
Converting Excel serial date numbers to standard date formats (e.g., 44567 → 2022/1/6)
Removing duplicates based on order IDs (SOID), keeping only the most recent records by date
Converting date strings with English month names to numeric formats (e.g., 06/Jan/2022 12:27 → 2022-1- ...
Posted on Fri, 08 May 2026 09:32:27 +0000 by m2babaey