CREATE TABLE Doctors ( doctor_id INT AUTO_INCREMENT PRIMARY KEY, doctor_name VARCHAR(100) NOT NULL, specialization VARCHAR(100), phone VARCHAR(15) ); CREATE TABLE Patients ( patient_id INT ...

Read this SQL tutorial to learn when to use SELECT, JOIN, subselects and UNION to access multiple tables with a single statement. It’s sometimes difficult to know which SQL syntax to use when ...

A few days ago I was tagged on a thread on Twitter: my old pal Mim was upset to find that he couldn’t use a SQL query with a Common Table Expression as the source of a table in DirectQuery mode. He ...

Subqueries on the right side of IN/ANY/SOME/ALL comparisons are fully executed and their results buffered into memory before the comparisons begin. This is undesirable in the case of large subqueries.

Abstract: XML is often used to represent objects that expose different sets of properties. This "property bag" scenario is a prominent use case for the XML support added to Microsoft SQL Server 2005.

Abstract: Expressing complex OLAP queries involving nested expressions using normal group-by, aggregation, and joins can be extremely difficult. We propose a technique that translates nested query ...