Follow this step-by-step guide to install PostgreSQL, load data, connect to a database, and execute SQL queries including table joins PostgreSQL is an open-source, object-relational (also called ...

Relational SQL databases, which have been around since the 1980s, historically ran on mainframes or single servers—that’s all we had. If you wanted the database to handle more data and run faster, you ...

The road to SQL started with Dr. E.F. Codd’s paper, “A Relational Model of Data for Large Shared Data Banks“, published in Communications of the ACM in June 1970. His colleagues at IBM, Donald ...

Even after 50 years, Structured Query Language, or SQL, remains the native tongue for those who speak data. It’s had impressive staying power since it was first coined the Structured Query English ...

Excel possesses formidable database powers. Creating a relational database starts with a Master table that links it to subordinates, called (awkwardly) Slave, Child, or Detail tables. Before we dive ...

Community driven content discussing all aspects of software development from DevOps to design patterns. The SQL specification defines four transaction isolation levels, although a fifth transaction ...