group by – Page 2 – CodeRavo

Combining and Aggregating Numerical Data in SQL

SQL provides powerful ways to manipulate numerical data within queries. This tutorial covers how to combine … Combining and Aggregating Numerical Data in SQLRead more

aggregate-function, arithmetic-operators, COALESCE, data manipulation, database-query, group by, null, SQL, sum

Removing Duplicate Rows in SQL

Removing Duplicate Rows in SQL Duplicate data can creep into any database over time, impacting data … Removing Duplicate Rows in SQLRead more

data integrity, database, delete, duplicate-rows, group by, performance, query, remove duplicates, row-number, SQL, transactions, window function

Selecting Distinct Rows Based on Multiple Columns in SQL

Introduction In relational databases, selecting distinct rows based on multiple columns is a common requirement when … Selecting Distinct Rows Based on Multiple Columns in SQLRead more

Aggregate Functions, anti-join, database performance, group by, null-handling, select-distinct, sql-update, subquery

Removing Duplicate Rows in SQL

Removing Duplicate Rows in SQL Duplicate data is a common problem in database management. It can … Removing Duplicate Rows in SQLRead more

cte, data cleaning, data integrity, Database Management, distinct, duplicate-rows, group by, row-number, SQL

Selecting Unique Rows with PostgreSQL's DISTINCT ON for Grouped Data

Introduction When working with SQL databases, particularly in applications that involve complex data aggregations or reporting, … Selecting Unique Rows with PostgreSQL's DISTINCT ON for Grouped DataRead more

distinct-on, group by, indexing, nulls-last, order-by, performance optimization, PostgreSQL, select, SQL