Learn how to count a character in a column in MySQL, PostgreSQL, and SQL Server. >>>
Monthly Archives: February 2025
Using LEFT OUTER JOIN With a WHERE Clause
Learn how to use LEFT OUTER JOIN with the WHERE clause in major SQL platforms. >>>
Alter Constraints in SQL
Learn what to do when you want to change an existing constraint in SQL. >>>
How to UPSERT (MERGE, INSERT … ON DUPLICATE UPDATE) in PostgreSQL?
Learn ways to upsert (UPDATE or INSERT) with a singular atomic operation using the PostgreSQL DBMS. >>>
What Is a Conceptual Data Model and Why Is It Important in SQL Design?
Learn about conceptual data modeling, the first step in database design. >>>
How to Represent Inheritance in a Database?
Learn three ways of representing inheritance in a database: table-per-hierarchy, table-per-class, and table-per-concrete-class. >>>
Generate SQL Insert Script From Excel Worksheet
Explore methods for generating SQL INSERT scripts from an Excel worksheet and best practices for ensuring a smooth execution process. >>>
Understanding WHERE 1=0 in SQL: When and Why to Use It
Discover several useful real-world applications for the WHERE 1=0 clause in SQL: metadata retrieval, query safety, dynamic conditions, and empty table creation. >>>
How to Calculate Percentage With an SQL Statement
Learn how to calculate a percentage with an SQL statement. >>>
Pattern Matching Functions in PostgreSQL
Learn about various pattern matching functions available for PostgreSQL queries. >>>